This is product I used to make my DIY polyurethane engine mounts: amzn.to/36dYAZW Here's the long awaited sequel to my how to diy polyurethane engine mounts video. In this video I answer two questions a lot of people asked: 1. How have my diy poly mounts held up and 2. What's the difference between stock and poly engine mounts?
You need to do another pour but this time do it with a few cavities in the bushing. Fill maybe 40 to 60% of the available space with poly instead of the full 100% of the space, that way you can tune the stiffness of the bushing. You might try mixing a little bit of liquid latex in also, may help soften it up a little.
I did like your video in which you made those bushings - except of course all the spilling. But compared to the old rubber bushings, that were not solid, and of course a much softer material than polyurethane, these mountings you made are way too hard, compared to the OEM part. I went thru this poly bushing idea before, although I bought mine from a company called "Polybushings", if I remember correctly. Later I found out, they bought those parts from another company, just doing Polyurethane stuff. I did like them, but I skipped on the engine mounts, because I was warned of the vibration. I used OEM rubber parts on there. But I didn't feel much difference on the suspension bushings I replaced. And also, it is safe from deteriorating if it comes in contact with oil. Happily so far, the engine is still dry. But thank you for the explanation, yet I believe, you could have skipped Audacity and just used a Decibel-o-meter.
Hi Emir. I noticed in the bike carb 1st start video that your front engine mount is factory rubber again. So the engine mount topic may not yet be finished. The factory revised the engine mounting in the I4 camry, probably earlier. They added a "ROD, ENGINE MOVING CONTROL: 12363-28061" between the cylinder head and the strut top. It does not support any engine weight so its very soft in comparison to the engine mounts. It is designed to act in 2 stages. At idle its a flexible rubber band for good NVH. Under torque it will deflect until the side blocks contact the support ring becoming very stiff to control powertrain wind up. This approach has less compromise than either the MR2 factory rubber or aftermarket urethane mounts. It's used in many cars so finding an example of a place to attach it and one of correct length should not be as hard as the other things you have done. parts.toyota.com/a/63033794__6708622/MOUNTING/286420-1107.html
An important issue when using stiffer engine mounts is, the increased stress on the metal around the mounts causing fatiguing and cracking. The rubber mounts absorb these stresses and vibrations but the PU mounts pass on the stresses and vibrations to another part of the car not built to take those conditions.
Just a caution - if you have an older car (like my 76) and you buy "stock" mounts for it, the only ones you can get today are coming from India and China, and even though they carry the same part number as the originals, they have terrifically hard urethane (80-90A) instead of what was used in the factory originals (45A hardness) from back in the day. So it's important to realize that "stock" doesn't mean what it used to. Thanks for taking the time to do all this work though, it's great stuff!
I actually enjoyed my 60A fill inserts. you feel more but once you get rid of any cabin rattles it is nice to feel more connected to the engine. Its the rattles that are unpleasant just eliminate them and it is golden.
Excellent video which told me exactly what I wanted to know and confirmed my suspicions. I recently bought a beautiful 65 GTO. It has a very stout cam, long tube headers and loud exhaust. It also has a very nice sound system. Despite the entire interior, trunk and doors being lined with Fatmat sound deadener everything vibrates. At first I chalked it up to the loud exhaust but got to thinking that would not explain the vibrations in the seat at idle. Today I looked at the engine mounts and, sure enough, they are Prothane. I'm going to switch to stock style mounts. Thanks.
So I replaced the Prothane mounts with rubber. The instant I started the engine I knew it was the right move. I didn't need to to the water glass test (though that is quite ingenious). Butt test was enough. Thanks again.
Someone mentioned in the comments 3M window weld. They give the shore hardness of this product around 50A. Reoflex 50 could have given a result closer to OEM. Thank you for these exceptional two videos. Keep up the good work, am watchin' ya 😊👍👍👍
The best way to do PU mounts is to either select a softer Pu formulation like a 60A or 70A or just fill one rear mount and leave the rest stock or drill some holes in your full PU mounts to create movement. The concept of PU mounts is that they last much longer than the OE rubber mounts.
Liked your honesty and your comparison of the two. I watched both videos too, and was very happy that you made a comprehensive follow up and comparison... Very cool of you to do!. Thanks for the uploads😎
+Casey - The Original Conspiracy Realist Thanks a lot for watching both vids and your feedback. I appreciate it. Really happy to hear you liked the content.
I did the 3m window weld polyurethane fill, and it idled amazingly smooth and held great with launches on my 99 prelude. The window weld looks a lot softer than this but it stopped wheel hop completely.
He's bang on... For a track car or weekender they are great and really change the feel of the car. But for a road going daily the rattle on tick over is almost unbearable. Definitely a lot worse in a diesel.
Excellent follow up video! I use poly when I'm increasing HP output on an engine because it absorbs the additional torque better with less engine movement.
First of all, thank you for the honest review. It is exactly what I had suspected from your first video of making it. The function of engine mounts is to absorb the vibration of the engine. As the engine get older, the vibration would be more. Therefore the DIY would defeat the purpose of fulfilling that function of absorbing the vibration as it is too stiff. Maybe having some gaps between the filling would compensate and reduce the stiffness. However, you need to make a mould for the pouring which likely to cost you.
Maybe because they didn't hear a word from the video. He could have put some more time to normalize (amplify and/or compress) the audio level of the video.
@MAkM Urethane _suspension bushings_ for any 'sporty spirited' driving = WIN. Urethane engine mounts on a street driven car.... NO, stay with stock. Urethane on any kind of luxury car = idiotic.
I already knew that polyurethane would be too hard, certainly from the fact that they are not hollow. But... What I appreciate the most is your honesty, thanks a lot for it..!
Hi ... I rally appreciate the effort you put into this presentation. So the stock mounts are best you think but I watched your previous video and the making of my own polyurethane mounts are appealing to me and are cheaper than the stock rubber mounts in the long haul. Thanks again for your video . You've got a subscriber from me for sure !
I was here trying to figure out poly vs rubber for my DeLorean.. and then I heard it 0:05. I checked my radio to make sure I didn't leave a cassette in the DeLorean playing, but no.. this man here.. is cultured in music. Greetings from VIN 4693!
You're the peoples champ man. What a brilliant set of videos. I think you outline how most people would feel, yet everyone on the forums say the only answer is polyurethane! Thank for take the time to on these videos.
Road Worthy Thanks for watching and staying tune. Lol for the pee urge, but it does make sense actually, at least to my limited understanding of human biology :)
Thanks the effort you went to saved me a lot of trouble as ride comfort and low vibration is more important to me and I am so glad I did not buy poly engine mounts.
So I’m not sure if this has been asked or not, but how would you go if you did drill holes in them to replicate the stock mounts, some of the noise and vibration may be coming from the fact there is no gap in the mount to take that out, the diy mounts being a solid state means the vibrations will be traveling directly to the rest of the car?
stated05 I’m thinking of doing this but using some small diameter tubing with some releasing agent to take up space and allow them to slide out after curing. I think better than stock is all that’s needed.
There's also softer durometer polyurethane. I think he might be using too hard of a duro for engine mounts. maybe something around 60a-70a durometer would be more comfortable, and closer to stock feel.
A very informative comparison. I was wondering if a combination is a better option for most folks by using polyurethane mounts at the hard-to-replace location and stock mount at the easy-to-replace location like the top strut mount.
Good comparison. The 'floating' aspect of the original rubber mounts dissipates the vibrations better. I replaced the transmission mount only and noticed the vibration difference, even after putting rubber on the inside mounting surfaces where metal meets metal. I really noticed a difference in performance, the power delivery is much better. Good luck in getting as many hits with this vid. :)
Dude you did a good job !! hopefully next video you can mould the Poly follow from the rubber pattern from the stocks ,, the results will be better . The stocks ' vibrated lesser because of the hollow-pattern were designed to absorb more vibration.
The hardness isn't the only consideration in terms of vibration, but also the contact area of the bushing to the mount, and the GEOMETRY of the material. I ran MONROE shock absorber's largest factory making all the OE (Original Equipment) for new automobiles. There are some bushings on a car that will benefit greatly from polyurethane, not just for ride improvements but also longevity of the part itself; like the bushings on the differential. I suspect that if you copied the shape of the original bushings and molded these parts apart from the main housing, then inserted them, you would find much better characteristics for vibration AND the benefits for high stress too, as well as longer lasting parts. ALL manufacturing companies chase pennies in savings to show cost improvements year over year, and none of the auto manufacturers can keep up with the greedy demands of stockholders anymore. I would use polyurethane FIRST on the suspension and steering bushings before the motor mounts. Engineered shorter life spans is a calculation to keep repair revenue UP for dealers and the aftermarket too. In the 1990's all the auto makers changed their view on QUALITY, to reduce costs and also increase sales $$$ (even repairs) they didn't want their cars or components to last TOO long! Nice video, great honesty! You're onto a winning pathway.
Thank you for the down and dirty comparison. I have to admit, I skipped to what I needed to know and without surprises can confirm - that poly for engine mounts is a no no.
You should do comparison when the transmission/engine is under load with regular driving and race track driving, the sound will be different and the engine movement is a lot different as well... Awesome video! Thanks!
I did this 20 years ago on my '89 Civic Si. I poured the engine mounts solid with 50a polyurethane. The increase in harshness and vibration from the engine was tremendous. It was for a race car, so I didn't mind. If you are doing this on a street car, your passengers will hate it. I imagine drilling holes to emulate the shape of the original mounts would have reduced the vibration, but it was a race car, so I just left it in torture mode. The mounts are super-strong and will wear out the rest of the car before they give a single millimeter.
The difference is not because of the meterial difference, but because of the way you filled. You fully filled polyurethane and there was no space left between both metal parts to get the vibration absorbed unlike stock mounts.
No matter final results This is a cool video The difference from stocks and DY is the design The stocks had pockets for vibrations Cool video and a lots of work
I like all of your videos. Interesting, informative and well explained. I particularly like the way you get to the topic quickly. I can't stand those videos where the host feels compelled to give you his life story before he gets to the point of the vid.
Nice video. Personally, what amazed me was that you were using Audacity - but then I looked it up and realized that it's available for Windows and Mac OS as well as Linux, which is what I use.
What was the Shore A hardness of the PU you used to make your bushes? I've noticed that one can buy different hardnesses ranging from 45 to 90. Standard rubber bushes would be roughly equivalent to 40 but also often have cavities to vary the stiffness in differing directions. 'Sports' and 'track' pu bushes are usually around 60 and 90 resp. maybe you could experiment with 'softer' PU?
I believe using 40A would work way better after all you fill up all the empty space unlike in the stock rubber mounts so even with same hardness you get it more stiff
Thanks, i was hesitated but since i am a daily driver. Decided not to install Polyurethane bushings based on your video. Specially, roads in Cairo are terrible.
You decided to make the replacement poly mounts (60A) which you said is softer than the replacement mounts (80A) and harder than the stock mounts (40A). I'm thinking that the softer 40A poly might have been a better option rather than a middle of the road choice to dampen vibration. Of course durability might be an issue or not, I don't know. What I do know is that the Right side motor mount on my 96' Riviera is completely shot and to replace it I have to lift the engine out because the serpentine belt passes through the motor mount bracket. (Thank you Buick engineers.) Pulling an engine can be expensive, so I want to get this right the first time. If I could buy a stock or replacement motor mount I would, but none exist... anywhere. Believe me I looked. And all the ones in the bone yard are shot too. The poly repair seems like the way to go, but if you or anyone has a better solution or suggestion I'd love to hear it.
I bet softer will still vibrate harder than stock. The main difference between the polyurethane filled mount and stock mount is the stock mount rubber has openings and those opening allow to flex the rubber more than solid polyurethane. He could make inserts for his castings to form those openings in the polyurethane so it would work like stock mounts.
@@illla 1cm or less, thick wood dovels wraped in paper tape (spaces in the urethane ) would do nicely once removed, to introduce softness, yet not compromise the strenght.
The problem is not with the Polyurethane material but rather you have filled the bush casing with polyurethane totally without leaving any gap or space for it to defuse the vibration created by the engine. This is the reason why the stock bush have gaps and hole in them to let the vibration stay at the joints rather than transfer to your chassis. I believe the polyurethane is better than the stock bush rubber because these days the manufacturer made it self destructed within a certain period.
Thanks for the honesty. After installing the COBB RMM for my MS3, I couldn't take it. The dash panels were literally coming loose and rattling, so were the side view mirrors. I uninstalled after a few weeks, but the damn thing had already caused some permanent damage and until now some panels are loose.
You should do a comparison of the same effect but include polyurethane inserts on oem rubber mounts, the idea being that the gaps are filled with polyurethane for stiffness In harder loads and then when cruising the rubber dampens vibrations
Just so you know, i took this idea and ran with it, a year down the line, the polyurethane that i injected on my stock control arm rubbers are still intact.
@@agcobileboqwana9923 hey that’s awesome! How does it feel inside the cabin? Can you notice any difference in ride quality? My mindset behind this idea was that oem rubber would provide dampening for the higher end frequencies that you tend to notice from the road, small bumps and rougher surfaces that you would notice more if you only had poly. But combining the two, would the poly be able to provide a stiffer response and hold tighter by restricting movement as well. I’m very curious to know if you can notice any differences first hand! And if it’s just negligible, I wonder if there would be any types of different poly/oem matrices that would provide the desired results. Some ideas off the top of my head being; layered, like a jawbreaker? Stagger between the layers in different shapes. And then maybe some kind of cross gridding? Similar to a carbon fibre layup, but in a 3 dimensional form? Would love to see what these types of ideas would bring about, I’m sure there would be some complexity in developing, but nevertheless, if you liked my last idea and tried it, I’ll gladly share more ideas 🙂 Thanks for getting back to me after 3 years, surprised you even thought to reply after a year of trials haha
@WPXTacoMan477, there's actually no vibration in the cabin, i put round hollow plastic spacers when i was pouring the 3m polyurethane, i didn't wanna drill the mounts, i think the vibration that's in the video is there because there were no holes left in the mounts to dampen vibration.
nan3r That from a physical stand point is why you should drill or cast these with holes. The material has elongation properties not being harvested in the solid form. Stress and strain are present and changing over the frequency and amplitude ranges. Holes allow these to decouple from the metal and dissipate the energy to the air. Hope that helps.
Snowy Owl “stress and strain are present and changing...” Agreed. “The material has elongation properties...” So you’re implying there is a benefit to using a higher modulus material with holes versus using a lower modulus material without, because the voids/decoupling allows better utilization of the material’s viscoelastic properties? Would be interesting to see this plotted. That is, determine an overall stiffness equivalent for both designs, then compare the dynamic response of the two
Many respects to the time and work you put into this. I sincerely love it! One question though, At what stiffness do your polyurethane mounts better go to compared to powerflex ones? for example if they are like racing series for a daily use it isn't worth it at all but if someone can make or put a little bit softer mounts for a daily use it could be somewhere in between and have less of the disadvantages. Keep it up. Already subscribed
Thank you, glad you liked the content. Powerflex and Prothane are usually in the 80-90a shore hardness category. I wanted something less stiff so the diy mounts you see in the video are 60a shore hardnees, but were still too stiff for me. I think the next step towards getting less noise, vibration and harshness would be to try and cast the mounts with hollow parts like OEM ones have, or to try and drill out the mounts. I went back to stock and am very happy, so maybe a project for a future race car or something :)
@@d4a that was a fast response. Wow. Well I was thinking about installing the yellow ones at my daily but after the video I had second thoughts as it seems there is a lot of vibration and would be waste of even that little money. So by the time these are even less stiff I guess the softest market polyurethane mount would be a headache. Thank you for the answer and the very informative video
the reason i watched first part of the video is that all my motor mounts are broken and the engine almost rotate 360 in the bay , the original mounts are expensive and i liked the idea, but then i was wondering about vibrations, well because mine are broken , the engine vibrates way too much , so i was sure with the polyurethane liquid will vibrate the same, then i came to see part two of the video and it is exactly how i thought. For me, remaking the broken mounts with poly isnt an option as they will vibrate the same as the broken ones :(, tho it is a nice project to remake broken ones and save for when the new ones will break and change with the diy til i get another pair.
I wonder about something in between. I would be interested in a poly DIY using a much softer durometer poly, one that is tougher than rubber for longevity but quite soft and pliable like rubber for vibration absorption.
What about if you use same material as the rubber mounts are made of and also same shape instead of filling them completely..probably you will need to make a JiG first over all good video Thanks!!
Around 6:50 in general it will not put more power to the wheels, it will allow power transferred quicker. Not a problem with mild stockish cars. But can be the difference between a good run and white smoking the tires in a stronger drag car where off the line traction can be an issue. In a rear wheel drive car with transmission, driveshaft and rear end angles. it can put more power to the wheels because it keeps everything in line with less give. NASCAR's for example can gain or loose 100hp to the tires with small tweaks to the driveline angles. That's why they dyno tune them on a chassis dyno.
I subscribe thanks for making this video it was very helpful I was going to get Poly Motor Mounts but the shaking and vibrations are too much for a daily driver car. Will go OEM thank you!
Several 20 mm holes on the perimeter of those mounts will allow them to Plex a little bit and may give you a hybrid between the movement of the original style rubber mounts and the what are functionally solid polyurethane mounts. Might be worth trying?
I'm doing this within the week so seeing your follow up video is really helpful as I had seen your original last year. We are going to do this for our old VW MK3.5 Cabrio.. two horizontal mounts (one on front of engine, one on transmission). Based on your update I think I will instead go with ReoFlex 50 instead of the 60 and I'm going to lightly grease the pin with vaseline to help keep it flexible as some people mentioned in your 1st DIY that some bush pins are made to move and rotate such as with control arm bushings in particular. Your thoughts on that?? - Secondly, I think I will also use a few 7mm rods I have on hand to make 6 additional holes on the mid line of the circle for added flex. I'm thinking those two things will get mine closer to the comfort of rubber with the durability of the poly while still adding a touch more stiffness. The car is a daily driver and while we are souping it up some, including a DIY engine rebuild soon with 8v to 16v conversion to got from 115hp to 160hp, we still want it to be a comfortable ride. A street car with some modest performance gains, but not a track car.
+Jeff Chartier Reoflex 50 and some holes should provide more comfort. The placement of the holes might be tricky and not straightforward. But the holes will do more for comfort than the difference between 50 and 60 shore hardness. When I made mine I imitated the factory design in which the pins do not move at all. I believe that the pins should not move in an engine mount, be sure to check the factory design of yours. Good luck!
Agreed on the movement, I checked mine and no pin movement. They do have slits though so I will add a few holes. I have a drill press and shop full of tools so this will be no problem. Cheers from San Diego CA.
Awesome and very precise review! One thing I missing is what grade of polyurethane did you use? Softer grade would do better? And also you should try it with holes on it as the stock mounts have it that will make a difference.
great effort, I found ur video while searching for lower arms POlyu bushings, I guess poly bushings is gonna take all the vibration into the steering, stock rubber somehow reduces the vibrations and cancel them
I prefer to swop the one that breaks first to poly Most likely, that one should have been stiffer from the factory Also less of the disadvantages I build my cars for enthusiastic street driving... Track days are very limited
So the mounts in my c Volkswagen TDI were shot. I replaced them with polyurethane ones. The vibration in the cabin is horrendous at idle. When driving its smooth. I'm gunna swap them out for the stock stiffness ones that are brand new. Much better choice imo.
This is product I used to make my DIY polyurethane engine mounts: amzn.to/36dYAZW
Here's the long awaited sequel to my how to diy polyurethane engine mounts video. In this video I answer two questions a lot of people asked: 1. How have my diy poly mounts held up and 2. What's the difference between stock and poly engine mounts?
You need to do another pour but this time do it with a few cavities in the bushing. Fill maybe 40 to 60% of the available space with poly instead of the full 100% of the space, that way you can tune the stiffness of the bushing. You might try mixing a little bit of liquid latex in also, may help soften it up a little.
driving 4 answers m
I did like your video in which you made those bushings - except of course all the spilling. But compared to the old rubber bushings, that were not solid, and of course a much softer material than polyurethane, these mountings you made are way too hard, compared to the OEM part.
I went thru this poly bushing idea before, although I bought mine from a company called "Polybushings", if I remember correctly. Later I found out, they bought those parts from another company, just doing Polyurethane stuff.
I did like them, but I skipped on the engine mounts, because I was warned of the vibration. I used OEM rubber parts on there. But I didn't feel much difference on the suspension bushings I replaced. And also, it is safe from deteriorating if it comes in contact with oil. Happily so far, the engine is still dry. But thank you for the explanation, yet I believe, you could have skipped Audacity and just used a Decibel-o-meter.
Hi Emir. I noticed in the bike carb 1st start video that your front engine mount is factory rubber again. So the engine mount topic may not yet be finished. The factory revised the engine mounting in the I4 camry, probably earlier. They added a "ROD, ENGINE MOVING CONTROL: 12363-28061" between the cylinder head and the strut top. It does not support any engine weight so its very soft in comparison to the engine mounts. It is designed to act in 2 stages. At idle its a flexible rubber band for good NVH. Under torque it will deflect until the side blocks contact the support ring becoming very stiff to control powertrain wind up. This approach has less compromise than either the MR2 factory rubber or aftermarket urethane mounts. It's used in many cars so finding an example of a place to attach it and one of correct length should not be as hard as the other things you have done.
parts.toyota.com/a/63033794__6708622/MOUNTING/286420-1107.html
Nice one bro ! This is where its at.
An important issue when using stiffer engine mounts is, the increased stress on the metal around the mounts causing fatiguing and cracking. The rubber mounts absorb these stresses and vibrations but the PU mounts pass on the stresses and vibrations to another part of the car not built to take those conditions.
Thumbs up for being so honest about your own (hard) work without the usual bias we'd see on UA-cam.
Just a caution - if you have an older car (like my 76) and you buy "stock" mounts for it, the only ones you can get today are coming from India and China, and even though they carry the same part number as the originals, they have terrifically hard urethane (80-90A) instead of what was used in the factory originals (45A hardness) from back in the day. So it's important to realize that "stock" doesn't mean what it used to. Thanks for taking the time to do all this work though, it's great stuff!
Do you have any idea as to why this occurred, the changing of the insert compound in these remanufacturing facilities in those countries?
I actually enjoyed my 60A fill inserts. you feel more but once you get rid of any cabin rattles it is nice to feel more connected to the engine. Its the rattles that are unpleasant just eliminate them and it is golden.
Finally somebody being truthful on UA-cam about PU bushings.
Thanks!
Very informative.
Excellent video which told me exactly what I wanted to know and confirmed my suspicions. I recently bought a beautiful 65 GTO. It has a very stout cam, long tube headers and loud exhaust. It also has a very nice sound system. Despite the entire interior, trunk and doors being lined with Fatmat sound deadener everything vibrates. At first I chalked it up to the loud exhaust but got to thinking that would not explain the vibrations in the seat at idle. Today I looked at the engine mounts and, sure enough, they are Prothane. I'm going to switch to stock style mounts. Thanks.
So I replaced the Prothane mounts with rubber. The instant I started the engine I knew it was the right move. I didn't need to to the water glass test (though that is quite ingenious). Butt test was enough. Thanks again.
@@65sohc butt test!! my sides rofl
Someone mentioned in the comments 3M window weld. They give the shore hardness of this product around 50A. Reoflex 50 could have given a result closer to OEM. Thank you for these exceptional two videos. Keep up the good work, am watchin' ya 😊👍👍👍
The best way to do PU mounts is to either select a softer Pu formulation like a 60A or 70A or just fill one rear mount and leave the rest stock or drill some holes in your full PU mounts to create movement. The concept of PU mounts is that they last much longer than the OE rubber mounts.
Do you happen to know the Rockwell hardness of the Prothane mounts?
@@inorite4553 it is shore hardness.
He used a polyurethane with a 60a shore rating
Liked your honesty and your comparison of the two. I watched both videos too, and was very happy that you made a comprehensive follow up and comparison... Very cool of you to do!.
Thanks for the uploads😎
+Casey - The Original Conspiracy Realist Thanks a lot for watching both vids and your feedback. I appreciate it. Really happy to hear you liked the content.
This has been so far the best comparasion i have seen on youtube, and i got all the answers i had. Good job m8
92bego Thanks a lot m8! Really happy to see you liked it.
I did the 3m window weld polyurethane fill, and it idled amazingly smooth and held great with launches on my 99 prelude. The window weld looks a lot softer than this but it stopped wheel hop completely.
Ton M thanks for sharing I ll try 3m!!!
Any1 else tried this ?
Do you also used it in suspension.
@@badtimegonesingh8883 yes I have used it on other cars
He's bang on... For a track car or weekender they are great and really change the feel of the car.
But for a road going daily the rattle on tick over is almost unbearable.
Definitely a lot worse in a diesel.
I'm in the USA and own a 94 JDM MR2 GT-S. Just wanted to say thanks for this video.
Well done! The back to back comparison is excellent.
Excellent follow up video! I use poly when I'm increasing HP output on an engine because it absorbs the additional torque better with less engine movement.
Tractor Wrangler I break engine mounts every 3 months poly or solids my only choices
First of all, thank you for the honest review. It is exactly what I had suspected from your first video of making it. The function of engine mounts is to absorb the vibration of the engine. As the engine get older, the vibration would be more. Therefore the DIY would defeat the purpose of fulfilling that function of absorbing the vibration as it is too stiff.
Maybe having some gaps between the filling would compensate and reduce the stiffness. However, you need to make a mould for the pouring which likely to cost you.
He put loads of time to put this video together showing us 30 idiots dislike the video... why
Maybe because they didn't hear a word from the video. He could have put some more time to normalize (amplify and/or compress) the audio level of the video.
@MAkM Urethane _suspension bushings_ for any 'sporty spirited' driving = WIN. Urethane engine mounts on a street driven car.... NO, stay with stock. Urethane on any kind of luxury car = idiotic.
I already knew that polyurethane would be too hard, certainly from the fact that they are not hollow. But... What I appreciate the most is your honesty, thanks a lot for it..!
Hi ... I rally appreciate the effort you put into this presentation. So the stock mounts are best you think but I watched your previous video and the making of my own polyurethane mounts are appealing to me and are cheaper than the stock rubber mounts in the long haul. Thanks again for your video . You've got a subscriber from me for sure !
I was here trying to figure out poly vs rubber for my DeLorean.. and then I heard it 0:05. I checked my radio to make sure I didn't leave a cassette in the DeLorean playing, but no.. this man here.. is cultured in music. Greetings from VIN 4693!
Was thinking about these for my 99 WJ but now I'm going to stay with stock. Thank-you for making this video.
You're the peoples champ man. What a brilliant set of videos. I think you outline how most people would feel, yet everyone on the forums say the only answer is polyurethane! Thank for take the time to on these videos.
Thanks for the insight, another side effect is female passengers have an increased urge to urinate! Lol, good OEM mounts is def the way to go.
Road Worthy Thanks for watching and staying tune. Lol for the pee urge, but it does make sense actually, at least to my limited understanding of human biology :)
Anyone elses stomach tighten when he set the mount on the sunroof?
Only you and the others with OCD. It's just a car. A POS car if anything. And on top of that, It's not like he dragged it along the paint.
@@paulnueberg742 Yeah, was expecting shattering glass. Lol
Watching this at the tailend of 2022. Thank you for this video! Subscriber from 🇵🇭
Thanks the effort you went to saved me a lot of trouble as ride comfort and low vibration is more important to me and I am so glad I did not buy poly engine mounts.
So I’m not sure if this has been asked or not, but how would you go if you did drill holes in them to replicate the stock mounts, some of the noise and vibration may be coming from the fact there is no gap in the mount to take that out, the diy mounts being a solid state means the vibrations will be traveling directly to the rest of the car?
stated05
I’m thinking of doing this but using some small diameter tubing with some releasing agent to take up space and allow them to slide out after curing. I think better than stock is all that’s needed.
Or using a soft PU, like 30 shore to 50 shore. Have no idea if it works
There's also softer durometer polyurethane. I think he might be using too hard of a duro for engine mounts. maybe something around 60a-70a durometer would be more comfortable, and closer to stock feel.
Well done, saved me from a lot of work changing to polyurethane. Keep up the good work.
A very informative comparison. I was wondering if a combination is a better option for most folks by using polyurethane mounts at the hard-to-replace location and stock mount at the easy-to-replace location like the top strut mount.
Good comparison. The 'floating' aspect of the original rubber mounts dissipates the vibrations better.
I replaced the transmission mount only and noticed the vibration difference, even after putting rubber on the inside mounting surfaces where metal meets metal. I really noticed a difference in performance, the power delivery is much better.
Good luck in getting as many hits with this vid. :)
+Car Dude Thank you :)
I made some too! First batch I f'd up, tried to add color and it just foamed up everywhere. Great video brutha! Keep it up!
Thanks, glad you liked the video. On my smooth-on dye it called for a just a few drops and it worked great.
Excellent video, was going to install Hinsons in my C6 Corvette, but not now, Thanks Mr Answer.
Dude you did a good job !! hopefully next video you can mould the Poly follow from the rubber pattern from the stocks ,, the results will be better .
The stocks ' vibrated lesser because of the hollow-pattern were designed to absorb more vibration.
Love this guy.. very humble.. and very very informative..i have shared his videos a lot in the aw1 comunitys
Legend. Channel Needs more support.
The hardness isn't the only consideration in terms of vibration, but also the contact area of the bushing to the mount, and the GEOMETRY of the material. I ran MONROE shock absorber's largest factory making all the OE (Original Equipment) for new automobiles. There are some bushings on a car that will benefit greatly from polyurethane, not just for ride improvements but also longevity of the part itself; like the bushings on the differential. I suspect that if you copied the shape of the original bushings and molded these parts apart from the main housing, then inserted them, you would find much better characteristics for vibration AND the benefits for high stress too, as well as longer lasting parts. ALL manufacturing companies chase pennies in savings to show cost improvements year over year, and none of the auto manufacturers can keep up with the greedy demands of stockholders anymore. I would use polyurethane FIRST on the suspension and steering bushings before the motor mounts. Engineered shorter life spans is a calculation to keep repair revenue UP for dealers and the aftermarket too. In the 1990's all the auto makers changed their view on QUALITY, to reduce costs and also increase sales $$$ (even repairs) they didn't want their cars or components to last TOO long! Nice video, great honesty! You're onto a winning pathway.
Good Video !!! You went a great length to make this Video for sure. Informative and Educational at the same time, THANK YOU !!!
A really interesting video, well done.
Andrew Denley Thank you, glad you liked it.
Thank you for the down and dirty comparison. I have to admit, I skipped to what I needed to know and without surprises can confirm - that poly for engine mounts is a no no.
Great job on your channel. Consider using a rear poly urethane mount and the rest stock mounts.
You should do comparison when the transmission/engine is under load with regular driving and race track driving, the sound will be different and the engine movement is a lot different as well...
Awesome video! Thanks!
A true scientist at heart. I wonder if you could possibly get more flexible polyurethane mounts? I believe you mentioned that on the 'making' video.
I like the water vibration demonstration best. That was smart.
Chuckled pretty good at the sound during the engine movement section. 😂
I did this 20 years ago on my '89 Civic Si. I poured the engine mounts solid with 50a polyurethane. The increase in harshness and vibration from the engine was tremendous. It was for a race car, so I didn't mind. If you are doing this on a street car, your passengers will hate it. I imagine drilling holes to emulate the shape of the original mounts would have reduced the vibration, but it was a race car, so I just left it in torture mode. The mounts are super-strong and will wear out the rest of the car before they give a single millimeter.
The difference is not because of the meterial difference, but because of the way you filled. You fully filled polyurethane and there was no space left between both metal parts to get the vibration absorbed unlike stock mounts.
On my AW11 I found the best combination to be stock trans and timing cover mount, but polyurethane inserts for the front and rear.
No matter final results
This is a cool video
The difference from stocks and DY is the design
The stocks had pockets for vibrations
Cool video and a lots of work
I like all of your videos. Interesting, informative and well explained. I particularly like the way you get to the topic quickly. I can't stand those videos where the host feels compelled to give you his life story before he gets to the point of the vid.
Perfect project... Well done my friend...
What country are you in? Love your videos BTW. You helped me repair my stock mounts on the cheap. Much appreciated.
Here's an answer to your question: ua-cam.com/video/xXSO_pgM_cc/v-deo.html. Glad the video was useful :)
@@d4a Don't know much about your country... but if I ever get rich maybe we can have a beer :) Much love from across the ocean
Here's to you getting rich! Cheers :)
Your an amazingly honest guy. Thanks for posting.
Nice video. Personally, what amazed me was that you were using Audacity - but then I looked it up and realized that it's available for Windows and Mac OS as well as Linux, which is what I use.
What was the Shore A hardness of the PU you used to make your bushes?
I've noticed that one can buy different hardnesses ranging from 45 to 90. Standard rubber bushes would be roughly equivalent to 40 but also often have cavities to vary the stiffness in differing directions. 'Sports' and 'track' pu bushes are usually around 60 and 90 resp.
maybe you could experiment with 'softer' PU?
Cyclone Cyd I made them in 60a. I thought it would be a nice balance between 45 stock and 90 track. Thanks for watching.
I believe using 40A would work way better after all you fill up all the empty space unlike in the stock rubber mounts so even with same hardness you get it more stiff
I think if you drill some holes like stock mounts had in them it would be a bit better. May take up more of the vibration, not all but some of it.
Thanks, i was hesitated but since i am a daily driver. Decided not to install Polyurethane bushings based on your video. Specially, roads in Cairo are terrible.
Definitely a good video leading you to the right direction 😊
You decided to make the replacement poly mounts (60A) which you said is softer than the replacement mounts (80A) and harder than the stock mounts (40A). I'm thinking that the softer 40A poly might have been a better option rather than a middle of the road choice to dampen vibration. Of course durability might be an issue or not, I don't know. What I do know is that the Right side motor mount on my 96' Riviera is completely shot and to replace it I have to lift the engine out because the serpentine belt passes through the motor mount bracket. (Thank you Buick engineers.) Pulling an engine can be expensive, so I want to get this right the first time. If I could buy a stock or replacement motor mount I would, but none exist... anywhere. Believe me I looked. And all the ones in the bone yard are shot too. The poly repair seems like the way to go, but if you or anyone has a better solution or suggestion I'd love to hear it.
Here's a better suggestion. Buy some urethane based windshield adhesive and inject it into the broken mount using a caulk gun.
You should try a 30a and stock mix just not a complete fill, but more if a support bracing combo. May improve the vibration concern.
Great demonstration of the topic. Thank you!
William Biggs Glad you liked it. Thank you for your comment.
If I remember, You used Shore 60 urethane. Have you had any experience with a 'softer' urethane, say Shore 30?
I bet softer will still vibrate harder than stock. The main difference between the polyurethane filled mount and stock mount is the stock mount rubber has openings and those opening allow to flex the rubber more than solid polyurethane. He could make inserts for his castings to form those openings in the polyurethane so it would work like stock mounts.
@@illla 1cm or less, thick wood dovels wraped in paper tape (spaces in the urethane ) would do nicely once removed, to introduce softness, yet not compromise the strenght.
The sound of the engine is totally smoother with the stock one.
Excellent video!!! You just talked me out of poly mounts for my 87 Corvette 383 "Grand Touring" project
Thank you for makin this video
The stock mounts sure do sounds better
use a softer shore compound, after all if you're casting them yourself and its still cheaper then buying them, what is there to lose?
What if you used the softer 30 polyurethane? Or a mixture of 30 & 60
I bet it would be softer. Just a guess.
Excellent video!
The problem is not with the Polyurethane material but rather you have filled the bush casing with polyurethane totally without leaving any gap or space for it to defuse the vibration created by the engine. This is the reason why the stock bush have gaps and hole in them to let the vibration stay at the joints rather than transfer to your chassis. I believe the polyurethane is better than the stock bush rubber because these days the manufacturer made it self destructed within a certain period.
I love my polyurethane bushings the vibrant don't brother me at all. Exhaust sounds the same and engine.
Thanks for the honesty. After installing the COBB RMM for my MS3, I couldn't take it. The dash panels were literally coming loose and rattling, so were the side view mirrors. I uninstalled after a few weeks, but the damn thing had already caused some permanent damage and until now some panels are loose.
Thank you for the demo. Awesome job comparing! 👏 👍
Nice Video and info, big help on my support engine design and modification. Thank you.
+Ernesto Villamor Thank you, glad it was useful.
Very good work thank you
You should do a comparison of the same effect but include polyurethane inserts on oem rubber mounts, the idea being that the gaps are filled with polyurethane for stiffness In harder loads and then when cruising the rubber dampens vibrations
Just so you know, i took this idea and ran with it, a year down the line, the polyurethane that i injected on my stock control arm rubbers are still intact.
@@agcobileboqwana9923 hey that’s awesome! How does it feel inside the cabin? Can you notice any difference in ride quality? My mindset behind this idea was that oem rubber would provide dampening for the higher end frequencies that you tend to notice from the road, small bumps and rougher surfaces that you would notice more if you only had poly. But combining the two, would the poly be able to provide a stiffer response and hold tighter by restricting movement as well.
I’m very curious to know if you can notice any differences first hand! And if it’s just negligible, I wonder if there would be any types of different poly/oem matrices that would provide the desired results. Some ideas off the top of my head being; layered, like a jawbreaker? Stagger between the layers in different shapes. And then maybe some kind of cross gridding? Similar to a carbon fibre layup, but in a 3 dimensional form? Would love to see what these types of ideas would bring about, I’m sure there would be some complexity in developing, but nevertheless, if you liked my last idea and tried it, I’ll gladly share more ideas 🙂
Thanks for getting back to me after 3 years, surprised you even thought to reply after a year of trials haha
@WPXTacoMan477, there's actually no vibration in the cabin, i put round hollow plastic spacers when i was pouring the 3m polyurethane, i didn't wanna drill the mounts, i think the vibration that's in the video is there because there were no holes left in the mounts to dampen vibration.
I'm loving the new intro
+Reluctant Couch Thanks!
Try to make some holes to the polyurethane.
Emanuele Moriggia that's right, he should try that, and share the result
you should try that, and share the result. ( I should try that and share the result ? ) WE SHOULD ALL ADD TO KNOWLEDGE VIDS.
Rully Rama Wijaya or just use a lower hardness. You effectively accomplish the same thing without introducing stress concentrations
nan3r That from a physical stand point is why you should drill or cast these with holes. The material has elongation properties not being harvested in the solid form. Stress and strain are present and changing over the frequency and amplitude ranges. Holes allow these to decouple from the metal and dissipate the energy to the air. Hope that helps.
Snowy Owl
“stress and strain are present and changing...”
Agreed.
“The material has elongation properties...”
So you’re implying there is a benefit to using a higher modulus material with holes versus using a lower modulus material without, because the voids/decoupling allows better utilization of the material’s viscoelastic properties?
Would be interesting to see this plotted. That is, determine an overall stiffness equivalent for both designs, then compare the dynamic response of the two
Brilliant.1 of the best videos I've watched. Great idea.
Awesome comparison video.
Very detailed and thought out.
Thank you.
Richard Short Glad you liked it. Thanks for watching.
Excellent effort, my utmost thanks.
Many respects to the time and work you put into this. I sincerely love it! One question though, At what stiffness do your polyurethane mounts better go to compared to powerflex ones? for example if they are like racing series for a daily use it isn't worth it at all but if someone can make or put a little bit softer mounts for a daily use it could be somewhere in between and have less of the disadvantages.
Keep it up. Already subscribed
Thank you, glad you liked the content. Powerflex and Prothane are usually in the 80-90a shore hardness category. I wanted something less stiff so the diy mounts you see in the video are 60a shore hardnees, but were still too stiff for me. I think the next step towards getting less noise, vibration and harshness would be to try and cast the mounts with hollow parts like OEM ones have, or to try and drill out the mounts. I went back to stock and am very happy, so maybe a project for a future race car or something :)
@@d4a that was a fast response. Wow.
Well I was thinking about installing the yellow ones at my daily but after the video I had second thoughts as it seems there is a lot of vibration and would be waste of even that little money. So by the time these are even less stiff I guess the softest market polyurethane mount would be a headache. Thank you for the answer and the very informative video
the reason i watched first part of the video is that all my motor mounts are broken and the engine almost rotate 360 in the bay , the original mounts are expensive and i liked the idea, but then i was wondering about vibrations, well because mine are broken , the engine vibrates way too much , so i was sure with the polyurethane liquid will vibrate the same, then i came to see part two of the video and it is exactly how i thought. For me, remaking the broken mounts with poly isnt an option as they will vibrate the same as the broken ones :(, tho it is a nice project to remake broken ones and save for when the new ones will break and change with the diy til i get another pair.
great videos man keep it up
bigmike 249 Thank you!
The mounts are supposed to eliminate the vibration so try make it as the stock shape inside the pin needs to move and eliminate the vibration
I wonder about something in between. I would be interested in a poly DIY using a much softer durometer poly, one that is tougher than rubber for longevity but quite soft and pliable like rubber for vibration absorption.
What about if you use same material as the rubber mounts are made of and also same shape instead of filling them completely..probably you will need to make a JiG first over all good video Thanks!!
Thank you, very good explanations.
Around 6:50 in general it will not put more power to the wheels, it will allow power transferred quicker. Not a problem with mild stockish cars. But can be the difference between a good run and white smoking the tires in a stronger drag car where off the line traction can be an issue.
In a rear wheel drive car with transmission, driveshaft and rear end angles. it can put more power to the wheels because it keeps everything in line with less give. NASCAR's for example can gain or loose 100hp to the tires with small tweaks to the driveline angles. That's why they dyno tune them on a chassis dyno.
I subscribe thanks for making this video it was very helpful I was going to get Poly Motor Mounts but the shaking and vibrations are too much for a daily driver car. Will go OEM thank you!
Awesome username :)
I got pneumatic mounts on my E46, it's pretty efficient to absorb vibrations.
Several 20 mm holes on the perimeter of those mounts will allow them to Plex a little bit and may give you a hybrid between the movement of the original style rubber mounts and the what are functionally solid polyurethane mounts. Might be worth trying?
From personal experience with a mazda Rx7 I used to own , poly urethane mounts are awesome . Stock mounts are soft like peanut butter 😂
Awesome, tks for the time and effort of sharing your knowledge
I'm doing this within the week so seeing your follow up video is really helpful as I had seen your original last year. We are going to do this for our old VW MK3.5 Cabrio.. two horizontal mounts (one on front of engine, one on transmission). Based on your update I think I will instead go with ReoFlex 50 instead of the 60 and I'm going to lightly grease the pin with vaseline to help keep it flexible as some people mentioned in your 1st DIY that some bush pins are made to move and rotate such as with control arm bushings in particular. Your thoughts on that?? - Secondly, I think I will also use a few 7mm rods I have on hand to make 6 additional holes on the mid line of the circle for added flex. I'm thinking those two things will get mine closer to the comfort of rubber with the durability of the poly while still adding a touch more stiffness. The car is a daily driver and while we are souping it up some, including a DIY engine rebuild soon with 8v to 16v conversion to got from 115hp to 160hp, we still want it to be a comfortable ride. A street car with some modest performance gains, but not a track car.
+Jeff Chartier Reoflex 50 and some holes should provide more comfort. The placement of the holes might be tricky and not straightforward. But the holes will do more for comfort than the difference between 50 and 60 shore hardness. When I made mine I imitated the factory design in which the pins do not move at all. I believe that the pins should not move in an engine mount, be sure to check the factory design of yours. Good luck!
Agreed on the movement, I checked mine and no pin movement. They do have slits though so I will add a few holes. I have a drill press and shop full of tools so this will be no problem. Cheers from San Diego CA.
Awesome and very precise review! One thing I missing is what grade of polyurethane did you use? Softer grade would do better? And also you should try it with holes on it as the stock mounts have it that will make a difference.
great effort, I found ur video while searching for lower arms POlyu bushings, I guess poly bushings is gonna take all the vibration into the steering, stock rubber somehow reduces the vibrations and cancel them
I prefer to swop the one that breaks first to poly
Most likely, that one should have been stiffer from the factory
Also less of the disadvantages
I build my cars for enthusiastic street driving...
Track days are very limited
So the mounts in my c
Volkswagen TDI were shot. I replaced them with polyurethane ones. The vibration in the cabin is horrendous at idle. When driving its smooth. I'm gunna swap them out for the stock stiffness ones that are brand new. Much better choice imo.