Yes very useful information. Getting ready to swap a set of heads in my sbf ho motor. Video couldn’t have come at a better time. Now I need a video on pistons to valve clearance and what’s the best way for a back yard machinist to clearance the piston if need be.
@@powellmachineinc3179 thanks just got done watching. Was wondering if you’ve put heads with a 2.02 valve on a stock bottom end ho motor and if it’s true that you have to open the piston pocket up? For the intake valve? From what I’ve come across is that there’s not enough room, radial ways. And that’s what you’ve got to grind or fly cut the piston for.
Fantastic video. I recently found out how push rod link works on shift rockers on my small block Chevy. Wish I had seen this video first with a save me a lot of time.
Might be worth mentioning to allow for the block & cyl head growth on all aluminium engines - this can decrease the preload by close to .020” at full operating temperature.
@@powellmachineinc3179sorry to butt in here but for my HC ls1 I measured 11 to 0 preload, I got Johnson 2110 lifters which require .035 preload +-.010, would you recommend I use .045 preload for the aluminum expansion?
one man man machine shop Been measuring for years try to run 0 lash on all hydralic lifters for years with no issues cams don't ware out with the right springs no valve issues
7 490 at zero is the longest I've seen yet. You obviously measured correctly, same way i do. Just was odd to hear that number since everyone ive done always falls into the 7.375, 7.400, 7.425 with preload added. Guess non milled heads and no block decking with a .05x head gasket and a small base circle cam there.
@@powellmachineinc3179 ahh copy that. Just started watching your videos recently. Well informed and straight to the point. Nice to see someone take pride in their work. Keep it up and thanks for your knowledge
That is all measured with everything cold. How do those measurement's change when the block and heads are hot and grow and what about cast iron block vs aluminum block?
This episode takes me back to another video you did . It was titled ' Customer accused me of not doing a valve job ' . Incorrect push rod length , excessive pre-load , would have produced similar results ...correct ?
What are the right questions to be asking your machinist to make sure you don't end up in a situation like you mentioned with the FE ford? Is it as simple as asking if they verify valve tip heights, or is there a smarter question to be asking?
Just tried this on my ls1, I got 11 turns out on my pushrod checker for zero lash. Did the math for .045 preload and got 7.395, I’m using Johnson 2110r lifters do you think if I use .050 preload so I can order 7.4 pushrods, you think it would be safe on that lifter? My setup is a stock bottom end ls1, torquer v4 cam and tsp ls6 brawler heads
@@powellmachineinc3179 .. I would be interested in purchasing one from you.. if you have one ready in the near future.. I know you are busy..so just let me know if you will be interested or not…and what I need to do..thanks !!
Makes sense as to why all the big LS cam companies sell whole cam kits with 7.400 pushrods. Obviously, every build is different, but in most cases, it's just some dude slapping a bigger cam and springs into a tired old vortec motor.
Couldn't you put the pushrod in purposely short like you did, then put an indicator on top of the rocker just above the pushrod to get it pretty darn close, then go from there? You're going to wear out the screw prematurely and get autheritis. Mike
they where 7.38" from factory, a ton of places sell factory replacements that are 7.4" though. ps yes I've measured multiple sets over a decade ago ( 7.38-7.385) is what i always got. gm even listed factory length as 7.38 in the org ls engine parts specs. this reminds me of the other 2 good ol ls valve train myths. i.e 1 turn is .050 preload and the other one of how ls lifters have 200" of plunger travel when in fact some gm ls7 lifters came with .126" of plunger travel.
@powellmachine the internet says.... There's varying heights on the LS cast rocker stand and to always use billet. Have you seen much height variance in the OE stand?
The Ford story explains why there is so much available preload travel on hydraulic lifters. It's there to take up those tolerance stack ups and machining diffefences.
I see my name on the white board behind you 😅 . How do you setup your sbc roller tip rockers on the valve tip i have see a couple different ways to set them thanks
Excellent information. Applicable to any pushrod equipped engine. side query: Are y'all gonna create an Odysee or Rumble channel? . . I'm trying to move away from anything google/yt, and if y'all were to do so, I would gladly watch your content over there. But, if you stick with yt, at least for now, I'll watch here. Either way, I'm still staying subscribed.
Always made sense to me to do it just like you show. 8" Calipers are less than $30. Set up to 0 lash, measure the length, add your desired preload, order the closest length pushrod. I read all the BS about counting turns of the rocker bolt, etc etc, and my head was spinning. I told them how I did it, just like you do it, and just got arguments. Coming from the solid roller BB chev world, LS is dirt simple.
Thread pitch of rockers studs can be measured and used as a tool, just exactly like HE said his pushrod length checker works by counting twist to Seay literally. However who would do that over an 8" caliper lol, I would use it as a check going together ( turns from 0 lash to Seat of bolt) just as a reference for future....this is the best way... I absolutely disagree on LS being easier, it's a non adjustable valve train..THIS part is all you get to do....ive run solid rollers on BBC on street with dissimilar metal bushings on down...ive run billet core hyd roller lobes with a solid roller lifter and spring pressure right in the middle boosted with a F1A-94 procharger that lived on the street forever but had to be precisely lashed cold... These ST2126SLR Johnson short travel lifters in my darton sleeved gen 4 block ( ls7 heads ) were the absolute most nightmare ever to get THEIR suggested .035 preload plus or minus .005, OH MY GOD 9 different lengths, which had to be custom ordered because as he mentioned most sell in increments of .025....lol.... It's just funny to read I'm like God I wish I could just lash these cold and check hot like my BBC's, once setup hopefully it's one and done but damn it wasn't easier ( .662 lift cam too)
Been watching your vids for some time now and are greatly impressed with your knowledge. I was all set to buy 3 used ls3 and bring them to you and have them machined and assembled the right way and not have a bit of concern.(since I'm only 20 miles away from y'all) now it'll be hard finding a machinest of your caliber. Thank you
Good video brother!!! You said to 600 lift and 625 to 635 lift. I am running a .617 intake and .619 exhaust. Does that mean I am in-between the 7.375 and the 7.400 pushrods? I was sent 7.400s with my kit I bought for my swap almost a year ago. Thank you for the content brother. You can never know everything, so you making videos I pick up a little more each time.
I don’t understand why the lift could have influence on the lifter preload? The zero lash is measured ont the base circle, and the lifter preload is also there to compensate Valve tip clearance when lifter rolls on base circle. So why are we talking about lift? Could you explain please?
I know nothing about V8s other than the basics of LS motors and what I've learned in these videos, but I just like watching and learning from someone who knows what they're talking about 😆. Plenty of information translates to other engines, too, which helps understand how something like engine block machining works and what's affected.
I haven't done an LS yet, but this is valuable info for the future. I notive you are working on an AFM block. What is the real scoop on AFM block valve train problems?
I had to run zero lash with my hydraulic cams in circle track or I would get a high rpm skip. By high rpm, I was running over 7,000 rpm in a 2 bbl limited modified class. I turned 7,400 at BHS and 7,200 at SD SFS.
🔔😎🇺🇲 OK, I read down in these comments where you said that this does NOT apply to adjustable rocker arms. I missed your saying that in the video. Can you do a video on adjustable arm geometry... Ill look over your older videos to see. Thanks for your great teaching sessions.👍👍
Hydraulic roller SBF with roller rockers. I was always told to spin the pushrod while tightening the rocker, as soon as there's resistance tighten 2 full turns. What's best? Lifters are shimmed for limited travel, more like solids if that matters.
Great video. Also watched your "DO ls7 lifters really exist" video. I'm new to building engines but my dads been around the block. I looked online and they said "ls7" lifters require .08-.100 preload. After watching both videos I now see this is false. Im just really stuck right now. So doing pushrod check at zero lash I got 7.235 Intake and 7.224 exhaust. You say the goal is 0.030-0.060 If I went with a 7.3 pushrod it makes intake preload 0.065 and exhaust 0.076 (outside of the .060 goal) But if I went 7.25 now intake and exhaust are under the goal. something like intake being 0.015 and exhaust 0.026 What would you recommend?
I have a Gen 4 LS2 with a BTR stage 2 cam kit and LS9 head gaskets. Im running .080 preload. BTR says 0.100. I measured a 7.5 pushrod. When i use the 7.4 pushrods from the kit, my valvetrain is mush much louder than it is with the 7.5 pushrods. Thoughts? Stock 243 heads with BTR dual valve springs amd Ti retainers.
Nice video! I was asked to advise someone on lifter preload recently. After my advice, we talked about the advice given from others about lifter preload. There is just some exotic imaginary things happening in people's heads sometimes. 😮 Thanks for the concise video on the topic!
There is another fellow making UA-cam videos (initials RH) doing a lot of dyno tests who claimed that the LS made more power with a longer pushrod. I asked him to explain HOW this could be....was it rocker geometry change or just the lifter slightly floating and increasing the effective duration? He got snotty with me (because he didn't know the answer) and just said 'It DOES'. I'm of the opinion like Mr Powell that less preload is better than more.
Those have oil passages in them and are opened up in DOD engines, to control the oil to the DOD lifters. This wasn't/isn't a DOD engine, so you see they look solid.
So an all aluminum LS engine with morel 7717 lifters takes .060 preload +/- .010 , is that one turn and a 1/8turn if one turn ? On a not adjustable oem ls rocker ONE TURN is .050 right?@powellmachineinc3179
I'm looking for a cam and lifters for a 5.7 hemi. can you help me out? It does not have that system that shuts the pistons down 2 4 cylinder does not have that system never did.
If you don't use enough preload with a high lift, higher load spring, it will resault in a loud valvetrain with factory travel lifters. The best thing to do is get a short travel lifters which will resault in minimal space under the lifter plunger and give enough preload for expansion. The spacer is not a bad idea too.
Thoughts on the old way of marking the tip of the valve with a marker, installing everything then rotating a few times. Where it wears thru the marker should be centered on valve stem…. Was told too far towards the valley it’s got too much push rod and opposite if west is toward the outside of the head. Would that be a geometry thing instead?
@@powellmachineinc3179 gotcha just making 100% sure because you got dudes out there still saying it. Now go do a video on non fixed lol, I can see on non fixed there being options and some are better than others?. Been binge watching your videos and man Iv learned a ton (20+yr mechanic) and it makes wanna work in a machine shop. Keep up the good work and videos!
You can shim the rocker stand but not really an issue till you start getting into some high lift over .600. At that point an aftermarket adjustable setup would be ideal
That's an old wives tale that just refuses to die. And the exact wrong way to find out pushrod length. If the contact patch is wrong on an adjustable height valvetrain, you have the wrong rockers. And the solution for the wrong rockers isn't pushrods that are way too short.
No one seems to talk about the torque spec on the rocker bolt. What if you torque the rocker bolt to zero lash then add .030-.060 to the length of the pushrod for preload.
Im happy to see someone who actually uses a pushrod tool instead of that turns crap..the method you use takes no time and can result in a more accurate reading..its also more accurate when you get into the reduced travel lifters like johnson
Question: If limiting the area the lifter pumps up is the goal; what difference does it make if the “travel” is at the top/bottom of the plunger travel? Running “Deep” preload is a cheap way of creating a limited travel lifter. Yes limited travel lifters are less forgiving. BTR recommends more preload for better control with higher spring pressure and rpm. Old school builders use to run 1/4 turn or less lifter preload to try and get every bit of lift available with the lifter pumped up.
Not to take away from anything you mentioned, but it's actually worse when you figure rocker ratio. 0.100 preload would become 0.170 or so at the valve if the lifter extended in a float situation. Thanks for sharing your knowledge!
Sounds like you need to be an engineer to build an LS? I have built dozens of SBC's without all this engineering. Was I just lucky that they all ran as expected? They were 327 or 350 from the 70's. Pink rods, trw 11.5 to 1 pistons and forged crank. Was I just lucky?
@@alanmeyers3957 I don't get it, a hydraulic cam/lifter combo means you tighten the rocker down to zero lash then another 1/2 turn case closed. What use is there for different length push rods when the lifter self adjusts?
Lifter travel has never been much of any use to start with. Why would you want to have a pump action that exceeds play plus material expansion!? 🙈 What is the expansion of an all alu compared to iron block, anyone know this?
Now, what about Short travel Johnsons vs reduced travel. The “internet” says you have to check every cylinder with Short travel. Why? Or is that even true. Any benefits to a short travel vs reduced travel vs stock style gatorman
@@powellmachineinc3179 .058 plunger travel on short travel. Only info i can find quickly on “reduced” travel is .005 shorter than a “LS7” lifter and the ability to not bleed down as fast as an oem lifter. Both have the same recommended preload of .035 +/- .010
Makes me want to swap out my 7.425 pushrods for my 7.400s now. I have ls7 lifters and everything I was seeing said to shoot for .100 preload so the 7.425s got me between .090-.095.
If you feel a little play in the rocker still, can't you measure the play with a dial indicator, then measure the length of the pushrod and add the measured play plus the desired preload? I do the same thing zeroing a rifle scope. If the bullet impact is 3.2 mils high, adjust the turret to plus 3.2 mils.
Limiting the amount that the lifter can pump up was my takeaway from today’s video. Thank you, sir.
Exactly
Yes very useful information. Getting ready to swap a set of heads in my sbf ho motor. Video couldn’t have come at a better time. Now I need a video on pistons to valve clearance and what’s the best way for a back yard machinist to clearance the piston if need be.
@@jcnpresser ua-cam.com/video/zRDK87OQ9Kw/v-deo.html
@@powellmachineinc3179 thanks just got done watching. Was wondering if you’ve put heads with a 2.02 valve on a stock bottom end ho motor and if it’s true that you have to open the piston pocket up? For the intake valve? From what I’ve come across is that there’s not enough room, radial ways. And that’s what you’ve got to grind or fly cut the piston for.
@@jcnpresser it's not difficult to check piston to valve clearance.
Thank you for explaining that and thank you for your time.
Glad it was helpful!
Thank you, for another insightful video!
My pleasure!
@@powellmachineinc3179 Daniel, if I had your brain, I'd throw mine in the trash!😃
Fantastic video. I recently found out how push rod link works on shift rockers on my small block Chevy. Wish I had seen this video first with a save me a lot of time.
Glad it helped
Might be worth mentioning to allow for the block & cyl head growth on all aluminium engines - this can decrease the preload by close to .020” at full operating temperature.
So ,this is exactly why we preload in the first place also a all aluminum Ls will only grow about. 010"
@@powellmachineinc3179sorry to butt in here but for my HC ls1 I measured 11 to 0 preload, I got Johnson 2110 lifters which require .035 preload +-.010, would you recommend I use .045 preload for the aluminum expansion?
one man man machine shop Been measuring for years try to run 0 lash on all hydralic lifters for years with no issues cams don't ware out with the right springs no valve issues
You will actually have lash when it gets up to temp, that's the purpose of preload.
7 490 at zero is the longest I've seen yet. You obviously measured correctly, same way i do. Just was odd to hear that number since everyone ive done always falls into the 7.375, 7.400, 7.425 with preload added. Guess non milled heads and no block decking with a .05x head gasket and a small base circle cam there.
It's because the head is tall, it has raised pads and longer valves
@@powellmachineinc3179 ahh copy that. Just started watching your videos recently. Well informed and straight to the point. Nice to see someone take pride in their work. Keep it up and thanks for your knowledge
@@nickgarrett2533 thank you! We really appreciate that
Thanks for your Time , all this information Is very useful , for any that want to build o keep rolling a High performance engine 🍻 .
Glad it was helpful!
I shoot for 0.020" lifter preload in sbc (sbc flat tappet has always been my bag up to today).
All iron I 💯 agree
That is all measured with everything cold. How do those measurement's change when the block and heads are hot and grow and what about cast iron block vs aluminum block?
That is the reason we need preload, preload is reduced at temp
Was curious if you knew how much it was reduced and should you bake that into the cold measurements.
@@fasst5511 roughly. 010 on a aluminum engine
This episode takes me back to another video you did . It was titled ' Customer accused me of not doing a valve job ' . Incorrect push rod length , excessive pre-load , would have produced similar results ...correct ?
Yes sir
What are the right questions to be asking your machinist to make sure you don't end up in a situation like you mentioned with the FE ford? Is it as simple as asking if they verify valve tip heights, or is there a smarter question to be asking?
Absolutely, if they don't have a stem hieght gauge....find another shop!
You can't skip math classes and expect to be a machinist. That's for sure.
Absolutely
Exactly right 💯😊
Just tried this on my ls1, I got 11 turns out on my pushrod checker for zero lash. Did the math for .045 preload and got 7.395, I’m using Johnson 2110r lifters do you think if I use .050 preload so I can order 7.4 pushrods, you think it would be safe on that lifter? My setup is a stock bottom end ls1, torquer v4 cam and tsp ls6 brawler heads
That should be fine
👍 Good stuff
Thanks 👍
Since you do not sell long block engines yet..is there anyone you could recommend purchasing one from 05 5.3 vin T …I live in Va. thanks !!
We sell them, I have on close to being ready, we are just EXTREMELY busy
@@powellmachineinc3179 .. I would be interested in purchasing one from you.. if you have one ready in the near future.. I know you are busy..so just let me know if you will be interested or not…and what I need to do..thanks !!
#1 never run near “zero” preload unless the lifter has real steel clips! Never trust the cheap wire clips.
Makes sense as to why all the big LS cam companies sell whole cam kits with 7.400 pushrods. Obviously, every build is different, but in most cases, it's just some dude slapping a bigger cam and springs into a tired old vortec motor.
Yup, unfortunately
Couldn't you put the pushrod in purposely short like you did, then put an indicator on top of the rocker just above the pushrod to get it pretty darn close, then go from there?
You're going to wear out the screw prematurely and get autheritis.
Mike
Yes, it's just not as accurate
Aren’t stocks push rods 7.380
No
they where 7.38" from factory, a ton of places sell factory replacements that are 7.4" though. ps yes I've measured multiple sets over a decade ago ( 7.38-7.385) is what i always got. gm even listed factory length as 7.38 in the org ls engine parts specs. this reminds me of the other 2 good ol ls valve train myths. i.e 1 turn is .050 preload and the other one of how ls lifters have 200" of plunger travel when in fact some gm ls7 lifters came with .126" of plunger travel.
Ya need to fix the typo in the video title.
Got it
Wow... that was quick. Well done.
@powellmachine the internet says....
There's varying heights on the LS cast rocker stand and to always use billet. Have you seen much height variance in the OE stand?
No, there pretty consistent
The Ford story explains why there is so much available preload travel on hydraulic lifters. It's
there to take up those tolerance stack ups and machining diffefences.
Definitely
I love you debunking bullshit. I love your channel.
Tyvm! We appreciate that
you helped me out thanks for the informative video with no bullshit
I see my name on the white board behind you 😅 . How do you setup your sbc roller tip rockers on the valve tip i have see a couple different ways to set them thanks
That video is coming
I learn something new on almost all of these videos. Thanks for taking the time to make them.
Absolutely 💯
Excellent information. Applicable to any pushrod equipped engine.
side query: Are y'all gonna create an Odysee or Rumble channel? . . I'm trying to move away from anything google/yt, and if y'all were to do so, I would gladly watch your content over there.
But, if you stick with yt, at least for now, I'll watch here. Either way, I'm still staying subscribed.
Never heard of that?
Always made sense to me to do it just like you show. 8" Calipers are less than $30. Set up to 0 lash, measure the length, add your desired preload, order the closest length pushrod.
I read all the BS about counting turns of the rocker bolt, etc etc, and my head was spinning. I told them how I did it, just like you do it, and just got arguments.
Coming from the solid roller BB chev world, LS is dirt simple.
Yep
Thread pitch of rockers studs can be measured and used as a tool, just exactly like HE said his pushrod length checker works by counting twist to Seay literally.
However who would do that over an 8" caliper lol, I would use it as a check going together ( turns from 0 lash to Seat of bolt) just as a reference for future....this is the best way...
I absolutely disagree on LS being easier, it's a non adjustable valve train..THIS part is all you get to do....ive run solid rollers on BBC on street with dissimilar metal bushings on down...ive run billet core hyd roller lobes with a solid roller lifter and spring pressure right in the middle boosted with a F1A-94 procharger that lived on the street forever but had to be precisely lashed cold...
These ST2126SLR Johnson short travel lifters in my darton sleeved gen 4 block ( ls7 heads ) were the absolute most nightmare ever to get THEIR suggested .035 preload plus or minus .005, OH MY GOD 9 different lengths, which had to be custom ordered because as he mentioned most sell in increments of .025....lol....
It's just funny to read I'm like God I wish I could just lash these cold and check hot like my BBC's, once setup hopefully it's one and done but damn it wasn't easier ( .662 lift cam too)
Been watching your vids for some time now and are greatly impressed with your knowledge. I was all set to buy 3 used ls3 and bring them to you and have them machined and assembled the right way and not have a bit of concern.(since I'm only 20 miles away from y'all) now it'll be hard finding a machinest of your caliber. Thank you
We are booked till the end of the year, check with me end of summer and we will see what the schedule looks like
Good video brother!!! You said to 600 lift and 625 to 635 lift. I am running a .617 intake and .619 exhaust. Does that mean I am in-between the 7.375 and the 7.400 pushrods? I was sent 7.400s with my kit I bought for my swap almost a year ago. Thank you for the content brother. You can never know everything, so you making videos I pick up a little more each time.
That is correct, 7.4 should be fine
Woohoo, thank you sir!!!
I don’t understand why the lift could have influence on the lifter preload? The zero lash is measured ont the base circle, and the lifter preload is also there to compensate Valve tip clearance when lifter rolls on base circle. So why are we talking about lift? Could you explain please?
I know nothing about V8s other than the basics of LS motors and what I've learned in these videos, but I just like watching and learning from someone who knows what they're talking about 😆. Plenty of information translates to other engines, too, which helps understand how something like engine block machining works and what's affected.
Glad it helps! That's our goal
What about anti pump up lifters?.......Great video's.......😎😎
Snake oil
I haven't done an LS yet, but this is valuable info for the future. I notive you are working on an AFM block.
What is the real scoop on AFM block valve train problems?
This block is not afm, it wasn't available on this engine.
I had to run zero lash with my hydraulic cams in circle track or I would get a high rpm skip. By high rpm, I was running over 7,000 rpm in a 2 bbl limited modified class. I turned 7,400 at BHS and 7,200 at SD SFS.
I assume the cam is on the base circle?
It better be
I just didn't catch you saying it. Just wanted to make sure I didn't mess it up.
Great job sir. Your common sense approach, excellent explanation and perfect visuals leave no grey areas. Thank you for your channel.
You are very welcome
Thanks for the Video, hope you keep doing them!!!
That's the plan!
🔔😎🇺🇲
OK, I read down in these comments where you said that this does NOT apply to adjustable rocker arms.
I missed your saying that in the video.
Can you do a video on adjustable arm geometry... Ill look over your older videos to see.
Thanks for your great teaching sessions.👍👍
I have one coming
Would have left it, the typo was eyecatching. Thank you for sharing your wisdom.
Lol, well...
7.325 was the length pushrods i used for an lq4. Heads and block decked lightly with mild RV cam. 200,000 on engine and going strong. Daily driver.
Thanks for sharing some actual truth on this subject.
Getting close to that 25k giveaway!! Haha. Keep up the good work man
100%
Hydraulic roller SBF with roller rockers. I was always told to spin the pushrod while tightening the rocker, as soon as there's resistance tighten 2 full turns.
What's best? Lifters are shimmed for limited travel, more like solids if that matters.
2 full turns is insanity, 1/2 a turn is std procedure
@@powellmachineinc3179 Thank you so much!
Thanks for explaining that, there is so much out there that is just confusion.
You bet! It's like white noise...
Thank you! Nicely explained.
You're welcome!
Appreciate ya sharing good info coming from a pro
Glad to help
Thanks for the video "Facebook Bob"
You're welcome
Great video. Also watched your "DO ls7 lifters really exist" video. I'm new to building engines but my dads been around the block. I looked online and they said "ls7" lifters require .08-.100 preload. After watching both videos I now see this is false. Im just really stuck right now. So doing pushrod check at zero lash I got 7.235 Intake and 7.224 exhaust. You say the goal is 0.030-0.060
If I went with a 7.3 pushrod it makes intake preload 0.065 and exhaust 0.076 (outside of the .060 goal)
But if I went 7.25 now intake and exhaust are under the goal. something like intake being 0.015 and exhaust 0.026
What would you recommend?
7.3 would not be a deal breaker at all
@@powellmachineinc3179 awesome thanks boss! 🤝🏻
I have a Gen 4 LS2 with a BTR stage 2 cam kit and LS9 head gaskets. Im running .080 preload. BTR says 0.100. I measured a 7.5 pushrod. When i use the 7.4 pushrods from the kit, my valvetrain is mush much louder than it is with the 7.5 pushrods. Thoughts? Stock 243 heads with BTR dual valve springs amd Ti retainers.
Once you achieve preload adding more won't make more or less "noise" , noise is the absence of preload or internal issues with the lifter.
Question
Does it make a difference if you soak the lifters in oil for x amount of time compared to just coat lifter of oil and install?
It doesn't effect pushrod length
@@powellmachineinc3179 thank you.
Nice video! I was asked to advise someone on lifter preload recently. After my advice, we talked about the advice given from others about lifter preload. There is just some exotic imaginary things happening in people's heads sometimes. 😮 Thanks for the concise video on the topic!
There is another fellow making UA-cam videos (initials RH) doing a lot of dyno tests who claimed that the LS made more power with a longer pushrod. I asked him to explain HOW this could be....was it rocker geometry change or just the lifter slightly floating and increasing the effective duration? He got snotty with me (because he didn't know the answer) and just said 'It DOES'. I'm of the opinion like Mr Powell that less preload is better than more.
Yup
I am not Familiar with LS engines at all , what are the 8 pillars in the valley for?
Kit from down under
Those have oil passages in them and are opened up in DOD engines, to control the oil to the DOD lifters. This wasn't/isn't a DOD engine, so you see they look solid.
@@funfun8095 instant for cutting fuel on low load to save fuel , I looked up DOD from your reply?
Dod system
Outstanding explanation ! Thanks for the insight 👏
My pleasure!
Im by no means an engine builder but i get ur oount. I always out very lil preload on lifters, 1/4 turn mayb. Which is about. 015
That's to light on a all aluminum engine
So an all aluminum LS engine with morel 7717 lifters takes .060 preload +/- .010 , is that one turn and a 1/8turn if one turn ? On a not adjustable oem ls rocker ONE TURN is .050 right?@powellmachineinc3179
Another really helpful video. Thank you.
You're very welcome!
liked it
Ty!
I'm looking for a cam and lifters for a 5.7 hemi. can you help me out? It does not have that system that shuts the pistons down 2 4 cylinder does not have that system never did.
Yes
Nice to see an honest machinist...
I try
Another great vid on fixed rocker pre load and pushrod length.
Thanks 👍
Great info man thanks.
You bet
great information on the vidoes👊
Glad you like them!
Thanks for all the info.
You bet!
If you don't use enough preload with a high lift, higher load spring, it will resault in a loud valvetrain with factory travel lifters. The best thing to do is get a short travel lifters which will resault in minimal space under the lifter plunger and give enough preload for expansion. The spacer is not a bad idea too.
Lift is irrelevant, lifter function doesn't change from cam lift
Thoughts on the old way of marking the tip of the valve with a marker, installing everything then rotating a few times. Where it wears thru the marker should be centered on valve stem…. Was told too far towards the valley it’s got too much push rod and opposite if west is toward the outside of the head. Would that be a geometry thing instead?
Again, this is a fixed rocker system, that doesn't apply to non adjustable valve trains.
@@powellmachineinc3179 gotcha just making 100% sure because you got dudes out there still saying it. Now go do a video on non fixed lol, I can see on non fixed there being options and some are better than others?. Been binge watching your videos and man Iv learned a ton (20+yr mechanic) and it makes wanna work in a machine shop. Keep up the good work and videos!
You can shim the rocker stand but not really an issue till you start getting into some high lift over .600. At that point an aftermarket adjustable setup would be ideal
That's an old wives tale that just refuses to die. And the exact wrong way to find out pushrod length.
If the contact patch is wrong on an adjustable height valvetrain, you have the wrong rockers. And the solution for the wrong rockers isn't pushrods that are way too short.
@@davidbright1489 will do, I have some coming down the line
No one seems to talk about the torque spec on the rocker bolt. What if you torque the rocker bolt to zero lash then add .030-.060 to the length of the pushrod for preload.
9nce the rocker is seated you could torque it till the thread's pulled out and it can't change the preload because the rocker can't move any more.
@@powellmachineinc3179correct but I’m talking about torquing the bolt at zero lash, no more, then add length to the pushrod to obtain proper preload
Im happy to see someone who actually uses a pushrod tool instead of that turns crap..the method you use takes no time and can result in a more accurate reading..its also more accurate when you get into the reduced travel lifters like johnson
Absolutely
Great information.
Glad it was helpful!
Question: If limiting the area the lifter pumps up is the goal; what difference does it make if the “travel” is at the top/bottom of the plunger travel?
Running “Deep” preload is a cheap way of creating a limited travel lifter. Yes limited travel lifters are less forgiving. BTR recommends more preload for better control with higher spring pressure and rpm.
Old school builders use to run 1/4 turn or less lifter preload to try and get every bit of lift available with the lifter pumped up.
Watch the video again, I answer the question clearly
Not to take away from anything you mentioned, but it's actually worse when you figure rocker ratio. 0.100 preload would become 0.170 or so at the valve if the lifter extended in a float situation. Thanks for sharing your knowledge!
In a ls your 0.600 lift cam suddenly becomes a 0.770 lift cam!
Absolutely correct
Sounds like you need to be an engineer to build an LS? I have built dozens of SBC's without all this engineering. Was I just lucky that they all ran as expected? They were 327 or 350 from the 70's. Pink rods, trw 11.5 to 1 pistons and forged crank. Was I just lucky?
The exact same principles apply to all engines, even more on a stud mounted rocker.
The point of the video, from what I understand is, set pushrod length for minimum preload.
@@alanmeyers3957 I don't get it, a hydraulic cam/lifter combo means you tighten the rocker down to zero lash then another 1/2 turn case closed. What use is there for different length push rods when the lifter self adjusts?
did you do this with dry lifters or ones soaked in oil? or does it not matter?
It's irrelevant
Should you check with the heads bolted down?
I'm confused? The head is bolted down.
Great video. Having never done any of this, I had no idea it was actually fairly involved. The explanation was crystal clear.
Glad you enjoyed it!
Thank you
You're welcome
Same process apply to a factory roller cam small block?
No because the rocker can change its fulcrum hieght
Makes perfect sense. Thanks for the video.
Glad it was helpful!
Another great video! I have always set the preload as small as possible and have never had an issue. Thanks for sharing your knowledge with us!
Right on
I know this is your job and business. Do you have a video on how you learned your trade. Fascinating to me
A origin story video is coming
@@powellmachineinc3179 cool thank you sir
Do you see a lot of issues with prc heads?
Only the 2nd set thats ever been in my shop
Hi Daniel, thanks for the information! Now this video only pertains to (non) adjustable rocker arms?
The preload of a hydraulic lifter is across the board, but in a stud mounted system it's 2 fold, preload plus geometry
@@powellmachineinc3179 Yes, I just wanted to clarify Positive stop or adjustable on the push rod length deal!Thanks Daniel!
@@powellmachineinc3179
That's what confuses me vs this pushrod length method.
Geometry.. the sweep of the contact patch on the valve stem.
@hotrodray6802 I'm going to do a video on a adjustable rocker system
Thanks for the video!
You're welcome!
Lifter travel has never been much of any use to start with. Why would you want to have a pump action that exceeds play plus material expansion!? 🙈 What is the expansion of an all alu compared to iron block, anyone know this?
Many variables in how much lash grows, but .006-.015 is the average window depending on all variables
Where is this shop located?
Now, what about
Short travel Johnsons vs reduced travel. The “internet” says you have to check every cylinder with Short travel. Why? Or is that even true. Any benefits to a short travel vs reduced travel vs stock style gatorman
How much travel is "reduced travel "?
How much is "short travel "?
How much is your lifter bleeding in a cycle?
@@powellmachineinc3179 .058 plunger travel on short travel. Only info i can find quickly on “reduced” travel is .005 shorter than a “LS7” lifter and the ability to not bleed down as fast as an oem lifter.
Both have the same recommended preload of .035 +/- .010
Makes me want to swap out my 7.425 pushrods for my 7.400s now. I have ls7 lifters and everything I was seeing said to shoot for .100 preload so the 7.425s got me between .090-.095.
No such thing as a "ls7" lifter...I have a video on it
@@powellmachineinc3179 ok the ones the places call "ls7" lol
@@powellmachineinc3179so new gm lifters aren't as good of a design as the older style, in terms of oil band location?
Thank you for your knowledge and video's USA 🇺🇸 TRUMP
💯
If you feel a little play in the rocker still, can't you measure the play with a dial indicator, then measure the length of the pushrod and add the measured play plus the desired preload? I do the same thing zeroing a rifle scope. If the bullet impact is 3.2 mils high, adjust the turret to plus 3.2 mils.
Because od rocker ratio it's not as accurate, but yes