Do a video on the gdi mitsi heads best down draft factory port I know of... there is ways of dailing in slave cam cylinder heads reposition dowel /key or make off set dowel/key or remove and weld in at desired or recommend cam angle degree to suit application
Overlap happens a few degrees after the intake valve started to open and when the exhaust valve is a few degrees from closing, thus the intake air and exhaust gases will try to move around their respective valves. Wouldn't this be better for scavenging because the valves will be deflecting the air around them and thus the intake and exhaust streams would interact better? Also, it would seem that the proximity of the intake and exhaust valves with each other will affect scavenging effect the most (the closer the better), regardless of valve angle?
I had a 1993 corolla with the 4A-FE. So much fun driving it at 6000k rpm pedal to the floor on a mountain road. I joined a hill climb race with it once and got 4th over all in my category. I miss that car...
Cool! Intetesting because mine kicks in @6200 rpm and revs to 8250, its so cool to compare these statements! One revs to 6000, one hits lift after that. Edit: since everyone seems to miss their toyotas, I ain't selling my celica ts ever.
My dad bought his ae92 4afe corolla brand new from the factory in 1996, it currently has 490 000 kms, just an exhuast, engine has never been opened. Runs like a dream. I love the 4age BUT this video made me love and appreciate the 4afe even more ❤️ UPDATE: car currently has 502 000 kms 😁
AE92 chassis was 88-91, more squared off body. 92 was the next gen which I think was the AE101 with the rounded body and headlights. my car was a 90, buddy had a 92 which was the next body style.
Iive seen a tonne of car and engine theory vids over the years and dabbled a little bit and you always see examples of tradeoffs in engines, like you want more torque well you trade power etc. But this video really clearly explains how every little thing can affect an engine and its design. Cam timing, cam lift, valve size, valve angle, portsize, port angle. So. Many. Variables!!! But thats why its so awesome to get into cars, you could be like every other guy and drop an LS in a car because its a relatively easy way to get big power for decent money. But you man, you take an economy head and youre going to make it work because youre looking at the design and how the things they did for efficiency can help you make a fun, serious, and probably really unique engine. This is why I love this channel. No sheep doing the same tired old projects. Were breaking new-ish ground!!! So awesome and great job dude so excited for this one!!
I recently worked on my 1zzfe 1.8L Toyota Engine head. Literally I did my 1st top-overhaul, and it's also my 1st time removing the cylinder head. And yes, I can almost totally relate to what is explained in this very educational video. Great content. Thank you.
This was an amazing comparison, I was hoping for a comparison between the most modern 4AGE and 4AFE engines as I have owned both. The 4AFE was definitely a strong engine and I wanted to use it more a very lightweight vehicle.
Now you have it! I've bought my first 4A-FE car (a beautiful white 1988 Carina 2 liftback) because of your awesomely detailed videos. ;) Now that's the third 80s Toyota in my little collection and it sits right next to my 1988 3S-FE Camry and my 1987 3S-GE Celica convertible... I'm a happy fanboy... ^_^
There's some incorrect information on this video. 1) the heads compares are from a earlier Bigport 4A-GE, which was out from 1983 to 1987. The 4A-FE was made from 1987 to 2001. A better comparison would have been between a Smallport 16v 4A-GE and 4A-FE, as they would have been out at the same time. (Also, the smallport 4A-GE was around 10.5:1 compression ratio, meaning it was higher compression than its' FE counterpart, as opposed to lower compression vs the predecessor version of the GE). This would have been a better comparison, since that would allow the heads to be more properly compared. 2) @5:55 - Variable Valve Timing (toyota VVT) does not change the amount of lift, only the timing of the cam. This is confused with Variable Valve Timing with Lift (VVTL-i), which is only available on Toyota's 2ZZ-GE engine. Late models of the 4A-GE 20v had VVT, which would change the timing of the intake cam, based off hydraulic pressure, though it wasn't computer controlled. VVT does not in any way affect the lift or duration of valves, save for what can be done solely through timing. 3) @12:50 - He mentions that the narrow angle is due to better, newer design, however, the later 4A-GE 16v Smallport heads still utilize the wide angle intake ports, but carry more air into the combustion chamber than both the bigport 4A-GEs and the 4A-FE. (Though the smallport angles were lowered to 44 degrees vs the earlier 51 degrees). This is another example of it comparing later models with earlier models of different lines of the engine that work against it. it -is- accurate the more modern engines utilize narrower valve angles thanks to newer designs that help with this, notably: direct injection. However, the efficiency and power benefits from narrow angle valves were just considered at the time these engines were made, and that context in a comparison between the two can't be ignored. These are all relatively minor points in the grand scheme, but should be noted regardless.
God bless your videos. They just saved me tons of time of research with on point info and a clear direction for a technical documentation. Keep up the good work🤘👌
My friend has Corolla AE86 with this 4A-GE 16V engine (plus one spare engine for doing fun stuff like turbo, ITB, 20V head etc.) and I was so surprised how felxible this engine is and how fast can that car be with just 1.6 T-VIS heart under the hood. Fantastic piece of engineering.
I love you, you are like 10x more interesting than my university classes right now, thank you.. Keep up the awesome content! (Been planning some things for my car based on some knowledge from your videos :)
Thank you so much for being so specific! It is truly wonderful to not only see the physical differences, but an explanation of those differences as well. This does make me want to get another AW11 and turn a wrench on that 4AGE again! :)
@0:55 it's never a good sign when max HP of an engine is 300 rpm past redline. :P Just kidding. Your videos are always interesting. Thanks for the hard work.
Before I watch gotta say. this is info i have been searching for. building my own hybrid "A" and have always suspected the F would take turbo very well... now to watch and see what you think. =D
I love how you explain that simple, even I know most of the architectures applied to combustion engines, the options to improve one to the other, options and different flavors, I love car engines but I work as motorcycle mechanic, I peel my hands everyday working on different motorcycles and I'll keep doing it until I can't
Thanks for the video! My 1979 Honda cb750f motorcycle had 9.5k redline, narrow value angle, shims under cam and 10.5:1 compression. I think it made 78hp.
Because roads are overcrowded with «power machines», I prefer efficiency and did choose... a Citroën C1! The 50 kW are absolutely satisfying. I don't need more (anymore). Thanks for your videos! I do learn a lot! 😃🚗😃
The Volvo 850R head was very similar to the 4AGE head. Walkinshaw racing modified them for the super tourers by bolting in some additional metal to lift the intake valve angle and straighten the inlet runner. The result was an additional 60hp on that engine. The exhaust runner was left at a similar angle to the 4AGE exhaust because it flowed really well anyway.
If I remember correctly they shaved a wedge out of the the head surface to mount the whole head on a tilt, this made the intake port angle face more upright relative to the cylinder. That and machining the top third or so off the head to completely remake the main valvetrain section. Those engineers were amazingly creative in their way to work within the limits of rules and get around the fundamental limitations they had. My hats off to them for being so clever. As for the 4age 16V head I have seen the intake ports corrected by either machining a big chunk out of it and making the intake manifold reach right in or welding large sections up and machining / die grinding new ports. Both end up at the same goal of running the new ports through were the injectors would normally are located and hence ending up with a fairly modern looking port design.
question: by removing the excess casting on the exhaust ports on the 4afe and also shimming off some of the material on the shroud on the fe, does that promote more air velocity overall? if yes, how much of an improvement you would get thru hp and decrease in torque?
I commend you for the quality of the video, given just how much information you give I only have a small amount of additional information / corrections that I wish to add: - You mention different cam profiles and different lift with VVT. But for both times you show the VVT parts on the screen the parts are for variable angle only VVT systems, these still use a fixed cam profile and lift although it would be true for dual cam lobe or constantly variable lift VVT systems. You are however are completely correct with everything you said in regard to their variable phasing and the effect on factors such as the overlap. - When mentioning the later heads having a narrower valve angle on the screen the 20V 4age Blacktop is shown. This has the exact same 50 degree valve angle from the exhaust to the outer intake valves, but to be fair the middle intake valve angle is 37.7 degrees so that still counts as being partially narrower then? - The 2ZZGE and VTEC engines are forced to have rocker arms as having a twin cam lobe system is as far as I know impossible with a traditional bucket and shim system. That aside your point is still completely correct that OEM valvetrain in a 4age would in no way be able to handle the secondary cam profiles as used in the 2ZZ and Honda. - One thing not mentioned with the relation of the port velocity verses flow is that with a more upright port it can sustain a much higher port velocity before reaching the same air choke point. This significantly reduces the trade-off. It's also why modern heads can have a fairly small cross sections for their ports. A good example of this is the 3sge Beams engine, I wouldn't consider the ports to be overly large but flow amazingly well and can support high power without mods. Although you make very good points with how VVT does wonders to mitigate the issues with large CSA ports. - Alright so this one is just being pedantic and I know it's just what the common terminology is- pictured are adjustable cam pulleys, not gears. If it's driven by a belt then it's pulley. I can't fault anyone for using that term that is almost universally used regardless of if it's technically correct or not. Well anyway with that aside this isn't a criticism of your video, you clearly have done careful research here and your explanations for everything are excellent. I just commented in case you wanted some constructive feedback. I am completely open to correction on any of these points also. I thought you might find it interesting that did some mods to a 7afe head a while back and I was surprised to discover it had literally zero overlap between the cams. This isn't just by eye either, I put a dial indicator on that head when it was on the bench and I can confirm that the intake valves would fully close before the exhaust would open. Before this I didn't think any car engine had that. Oddly enough it had a reasonable amount of lift at a measured 8.34mm for the intake, weird.
I built an AE92 Corolla for Lucky Dog Racing League with an unmodified 4A-FE (ok, I baffled the oil pan and built a cold air intake from PVC pipe, but other than that, unmodified). there is jack shit for power above 5800 RPM, where I set the shift light. We held off some odd cars through 3rd gear but waved goodbye to their tail lights once pulling into 4th, and the explanation on valve angle effects kind of explains it. glad I didn't convert to the GE head though.
the only criticism i have (at this moment) would be more clear pronouncing of some words like 'scavenging effect' and 'pent roof'. I had to google for a few minutes before I found what you meant. this video was very well done, and was a superb learning tool about engines. I really enjoyed it. good clear explanations for some key concepts about engines. thanks a lot for showing us! really looking forward to more engaging content, you have a sub, here!!
Great Video. I've got a 4wd car with the 7AFE and the heads are very similar and this has kind of convinced me that a turbo on the existing head is probably smarter than a GE head :-)
@@AlexTrull7a-fe...... everything before the dash is the block, everything after is the head. 7a is the block...... the seventh generation of the A block, 1.8l and a longer stroke than the 4a, so the block is taller. The FE refers to the head, F is the narrow valve angle, E means it's injection. Your 7afe head is the exact same as the 4afe head.
I had just finished watching your quiz video on the inline 4 and so when I saw this I jumped at the chance to expand my knowledge. I grew up on old school Ford engines primarily the Windsor line so some of this stuff is completely new to me. However the trick with the hammer to get the valve retainers off it's actually a really damn cool trick! Probably wouldn't do something on high performance vehicle but just to pop them out of there that is really awesome!
2:44 how is changing the timing of the exhaust cam going to do "the exact opposite" on the intake cam??? Yes, they're locked together, but if you advance the one, it's gonna just advance the other by the same amount, and vice-versa...
Great video, but I think you switched the cams on the 4age, at least in the beginning. Because you can see the opening for the distributor cap on the right (exhaust side), but the cam with the gear to drive it is on the left (intake side).
This is the first video I've found from you (subbed around the 15 minute mark, awesome info) I think another good video if you haven't done it already is the subaru fa20 (brz/frs) compared to the fa20t from subarus other models
For the 4AFE it looks like it would be possible to put 4AGE cams. At 0:33 if you look at the FE head intake side you can see a metal insert that look like it could be removed. It would most likely take a little more modding to get them to work, like needing smaller gears.
The inlet camshaft would also need a seal, which would not fit, because the wall is thin, one can't machine out. I am pretty sure that with enough effort it could be done, some milling, and making a seal housing on the lathe, then assembling it to the head... But not just "enlarge the hole". Btw, according to the video, the 4A-FE head doesn't seem to be to much weaker than the GE, might be worth a try to tune as is, the real devil is in the intake manifold and the ECU, I guess. I have a Carina E by the way.
It amuses me at how old cars used rockers and new cars have gone back to this idea I've just changed my cam on my 2ltr pinto from 1971 and personally I much prefer the ease of adjusting valve clearance on rockers than shims. I do miss my mr2 with the 3sfe engine it was alot more fun to drive than the 3sgte mr2 I also had.
If I could suggest topics for this channel, one is capacitive discharge ignition and two, how to adjust variable timing cam gear, both intake and exhaust, as you show in this great video. Thank you.
I am not going to mess around with my 4AFE cylinder head. But if find it interesting that my car has 114 hp ( not 105) and my brother has 88hp on his 4EFE 1.3 while later they only had 75 for better emission and mileage. I think all of those changes where made by the ECU. So it seems to me that a mapping of the engine could give you extra power without even losening one bolt. ( not much on a non-turbo engine, but still something ). 320 000km corolla 1.6i, 114hp. If I ever would do anything, I would have a rebuild/full service of the head, and change the piston rings to make it perform as brand new... but it is still a surprisingly strong car in modern traffic at age 29 years.
Well, I def learned something about shim over bucket vs shim under bucket! Learned more about valve angles too. Plus more detail on those 4A heads of course. Excellent, excellent video as always.
Would tiny, tiny fin like structures on the valve side facing the intake port (machined on the valve disk in a slight spiral maybe?) help with better mixing of air and fuel in the combustion chamber? Help make the charge enter the cylinder in a mixing helping way :) Love your videos! fun and educational!
Check out racing 4age valves from manon racing performance, or even many other aftermarket racing and high performance valves. Many have something extremely similar to what you're describing.
at 1:16...why are the cams backwards in the 4age head? anyone else notice that? the one with the gear should be on the right as it drives the distributor...
Definitely already spotted by Dima Minko :) This is a junk head I just slapped together for the vid, wasn't even paying attention. Yes, the exhaust cam drives the distributor but otherwise it has the same exact specs as the intake cam.
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Do a video on the gdi mitsi heads best down draft factory port I know of... there is ways of dailing in slave cam cylinder heads reposition dowel /key or make off set dowel/key or remove and weld in at desired or recommend cam angle degree to suit application
And you are better off going shimless buckets less weight ect
The new cylinder head now are wide angle for better tumbling
Overlap happens a few degrees after the intake valve started to open and when the exhaust valve is a few degrees from closing, thus the intake air and exhaust gases will try to move around their respective valves. Wouldn't this be better for scavenging because the valves will be deflecting the air around them and thus the intake and exhaust streams would interact better?
Also, it would seem that the proximity of the intake and exhaust valves with each other will affect scavenging effect the most (the closer the better), regardless of valve angle?
I had a 1993 corolla with the 4A-FE. So much fun driving it at 6000k rpm pedal to the floor on a mountain road. I joined a hill climb race with it once and got 4th over all in my category. I miss that car...
AE101 are underrated
@@bryan10444 all is the AE92. I have a 1991 with the 4afe. Great little car. Once it has coil overs it will be much better than my 2020 corolla se 6mt
Cool! Intetesting because mine kicks in @6200 rpm and revs to 8250, its so cool to compare these statements! One revs to 6000, one hits lift after that.
Edit: since everyone seems to miss their toyotas, I ain't selling my celica ts ever.
6000k = 6million rpm lol
@@kennethstephens8046 yeah bro i hope its a liftback, those things lowered can almost be mistaken for ae86
My dad bought his ae92 4afe corolla brand new from the factory in 1996, it currently has 490 000 kms, just an exhuast, engine has never been opened. Runs like a dream. I love the 4age BUT this video made me love and appreciate the 4afe even more ❤️
UPDATE: car currently has 502 000 kms 😁
AE92 chassis was 88-91, more squared off body. 92 was the next gen which I think was the AE101 with the rounded body and headlights. my car was a 90, buddy had a 92 which was the next body style.
@@Zfrk I know, it's an ae92, in south africa we still had models of the ae92 on sale till 1996. We get our cars abit late
Nothing to be ashamed of with the 4afe all things considered.
They go surprisingly well too.
Any updates on kms?
Wow, just wow, I'm amazed by the knowledge and content that this guy creates.
Who-hoo!! Happy D4A Sunday, everyone! You're smarter and more interesting for having watched this video. Great job, fantastic channel, D4A!
The content you create is insanely eductional. No other channel makes videos at this level.
I'm an engineer myself (not automotive) and absolutely love your videos! Very knowledgeable, well explained and interesting. Keep up the good work!
Iive seen a tonne of car and engine theory vids over the years and dabbled a little bit and you always see examples of tradeoffs in engines, like you want more torque well you trade power etc. But this video really clearly explains how every little thing can affect an engine and its design. Cam timing, cam lift, valve size, valve angle, portsize, port angle. So. Many. Variables!!! But thats why its so awesome to get into cars, you could be like every other guy and drop an LS in a car because its a relatively easy way to get big power for decent money. But you man, you take an economy head and youre going to make it work because youre looking at the design and how the things they did for efficiency can help you make a fun, serious, and probably really unique engine. This is why I love this channel. No sheep doing the same tired old projects. Were breaking new-ish ground!!! So awesome and great job dude so excited for this one!!
I recently worked on my 1zzfe 1.8L Toyota Engine head. Literally I did my 1st top-overhaul, and it's also my 1st time removing the cylinder head. And yes, I can almost totally relate to what is explained in this very educational video. Great content. Thank you.
I fell very lucky to have the motor with the best information in UA-cam thanks to your chanel! Cheers from Spain!
Lucky , I have a VW 1.6 FSI with barely any information on it at all . Makes 115 HP at 6000rpm :)
doing the head job on my 5efe right now and this is the best explanation I've seen of how it actually works. Thank you very much!
This was an amazing comparison, I was hoping for a comparison between the most modern 4AGE and 4AFE engines as I have owned both. The 4AFE was definitely a strong engine and I wanted to use it more a very lightweight vehicle.
Been looking for a video exactly like this to compare both designs. Great work
Now you have it!
I've bought my first 4A-FE car (a beautiful white 1988 Carina 2 liftback) because of your awesomely detailed videos. ;)
Now that's the third 80s Toyota in my little collection and it sits right next to my 1988 3S-FE Camry and my 1987 3S-GE Celica convertible... I'm a happy fanboy... ^_^
Fenomenalan video, pozz iz Zagreba
There's some incorrect information on this video.
1) the heads compares are from a earlier Bigport 4A-GE, which was out from 1983 to 1987. The 4A-FE was made from 1987 to 2001. A better comparison would have been between a Smallport 16v 4A-GE and 4A-FE, as they would have been out at the same time. (Also, the smallport 4A-GE was around 10.5:1 compression ratio, meaning it was higher compression than its' FE counterpart, as opposed to lower compression vs the predecessor version of the GE). This would have been a better comparison, since that would allow the heads to be more properly compared.
2) @5:55 - Variable Valve Timing (toyota VVT) does not change the amount of lift, only the timing of the cam. This is confused with Variable Valve Timing with Lift (VVTL-i), which is only available on Toyota's 2ZZ-GE engine. Late models of the 4A-GE 20v had VVT, which would change the timing of the intake cam, based off hydraulic pressure, though it wasn't computer controlled. VVT does not in any way affect the lift or duration of valves, save for what can be done solely through timing.
3) @12:50 - He mentions that the narrow angle is due to better, newer design, however, the later 4A-GE 16v Smallport heads still utilize the wide angle intake ports, but carry more air into the combustion chamber than both the bigport 4A-GEs and the 4A-FE. (Though the smallport angles were lowered to 44 degrees vs the earlier 51 degrees). This is another example of it comparing later models with earlier models of different lines of the engine that work against it. it -is- accurate the more modern engines utilize narrower valve angles thanks to newer designs that help with this, notably: direct injection. However, the efficiency and power benefits from narrow angle valves were just considered at the time these engines were made, and that context in a comparison between the two can't be ignored.
These are all relatively minor points in the grand scheme, but should be noted regardless.
I've only just watched this now (July 2022) and noticed the same regarding variable valve lift being confused with variable valve timing
I'm a simple man, i like heads from any model!
Most men like some head.
I compared these 2 cylinder heads for a couple years. Wonderful presentation!
driving 4 answers, I think this is the beginning of a beautiful friendship.
One of my favorite channels.
Every single thing covered here is also true of the larger 3S-GE and 3S-GTE and their economy family members the 3S-FE and 5S-FE.
Always making well put together and high level of educational content
This guy really talks perfect. You can hear ever word clearly he is the best!!
God bless your videos. They just saved me tons of time of research with on point info and a clear direction for a technical documentation. Keep up the good work🤘👌
I like how you're explanation always goes into the engineering of the engine i dont think anybody else even does that that i know of
Thanks
My friend has Corolla AE86 with this 4A-GE 16V engine (plus one spare engine for doing fun stuff like turbo, ITB, 20V head etc.) and I was so surprised how felxible this engine is and how fast can that car be with just 1.6 T-VIS heart under the hood. Fantastic piece of engineering.
Hands down the best channel ever!!
best channel
I'm driving a Corolla daily witht the 4AFE. It's not a quick car, but the sound it makes is great! Not many people know this or mentioning it.
I love you, you are like 10x more interesting than my university classes right now, thank you.. Keep up the awesome content! (Been planning some things for my car based on some knowledge from your videos :)
Thank you so much for being so specific! It is truly wonderful to not only see the physical differences, but an explanation of those differences as well.
This does make me want to get another AW11 and turn a wrench on that 4AGE again! :)
@0:55 it's never a good sign when max HP of an engine is 300 rpm past redline. :P Just kidding. Your videos are always interesting. Thanks for the hard work.
Saw 99 comments.
Love you bro. Just wanted to get you into triple digits.
100😎
You have so much knowledge of the simplest things of an engine I am amazed and thankful for you sharing your information!
Before I watch gotta say. this is info i have been searching for. building my own hybrid "A" and have always suspected the F would take turbo very well... now to watch and see what you think. =D
Had a 4afe with a manual, great little peppy engine but the 4age was leagues ahead.
Man, i'm in love with your channel, very well done.
I love how you explain that simple, even I know most of the architectures applied to combustion engines, the options to improve one to the other, options and different flavors, I love car engines but I work as motorcycle mechanic, I peel my hands everyday working on different motorcycles and I'll keep doing it until I can't
Really good stuff man! Dropping a comment to help out the algorithm.
Love this videos you allways learn something good. Ceep up the good work look forward to next.
Thanks for the video! My 1979 Honda cb750f motorcycle had 9.5k redline, narrow value angle, shims under cam and 10.5:1 compression. I think it made 78hp.
The background music is good also 😅
Good head has its benefits lmao
Always like your videos when I want to gain knowledge about engines. Thanks and keep up the marvelous work!
I bought a 96 Corolla for $1800 w/188k miles. I sold it last year with 358k miles for $300
I always love watching these vids because despite all I've learned, there's always more info to be found! Thanks for sharing with us
Before I even seen the title or channel, I could tell by the thumb nail that D4A dropped a video!!!
Because roads are overcrowded with «power machines», I prefer efficiency and did choose... a Citroën C1! The 50 kW are absolutely satisfying. I don't need more (anymore). Thanks for your videos! I do learn a lot! 😃🚗😃
The Volvo 850R head was very similar to the 4AGE head. Walkinshaw racing modified them for the super tourers by bolting in some additional metal to lift the intake valve angle and straighten the inlet runner. The result was an additional 60hp on that engine. The exhaust runner was left at a similar angle to the 4AGE exhaust because it flowed really well anyway.
If I remember correctly they shaved a wedge out of the the head surface to mount the whole head on a tilt, this made the intake port angle face more upright relative to the cylinder. That and machining the top third or so off the head to completely remake the main valvetrain section. Those engineers were amazingly creative in their way to work within the limits of rules and get around the fundamental limitations they had. My hats off to them for being so clever. As for the 4age 16V head I have seen the intake ports corrected by either machining a big chunk out of it and making the intake manifold reach right in or welding large sections up and machining / die grinding new ports. Both end up at the same goal of running the new ports through were the injectors would normally are located and hence ending up with a fairly modern looking port design.
@@Samqdf please share a link showing this mod
huge respect man i learn a lot from you
one video and I feel a lot smarter already! coool and thank you!
question: by removing the excess casting on the exhaust ports on the 4afe and also shimming off some of the material on the shroud on the fe, does that promote more air velocity overall? if yes, how much of an improvement you would get thru hp and decrease in torque?
Another great video! Good job my friend!
I commend you for the quality of the video, given just how much information you give I only have a small amount of additional information / corrections that I wish to add:
- You mention different cam profiles and different lift with VVT. But for both times you show the VVT parts on the screen the parts are for variable angle only VVT systems, these still use a fixed cam profile and lift although it would be true for dual cam lobe or constantly variable lift VVT systems. You are however are completely correct with everything you said in regard to their variable phasing and the effect on factors such as the overlap.
- When mentioning the later heads having a narrower valve angle on the screen the 20V 4age Blacktop is shown. This has the exact same 50 degree valve angle from the exhaust to the outer intake valves, but to be fair the middle intake valve angle is 37.7 degrees so that still counts as being partially narrower then?
- The 2ZZGE and VTEC engines are forced to have rocker arms as having a twin cam lobe system is as far as I know impossible with a traditional bucket and shim system. That aside your point is still completely correct that OEM valvetrain in a 4age would in no way be able to handle the secondary cam profiles as used in the 2ZZ and Honda.
- One thing not mentioned with the relation of the port velocity verses flow is that with a more upright port it can sustain a much higher port velocity before reaching the same air choke point. This significantly reduces the trade-off. It's also why modern heads can have a fairly small cross sections for their ports. A good example of this is the 3sge Beams engine, I wouldn't consider the ports to be overly large but flow amazingly well and can support high power without mods. Although you make very good points with how VVT does wonders to mitigate the issues with large CSA ports.
- Alright so this one is just being pedantic and I know it's just what the common terminology is- pictured are adjustable cam pulleys, not gears. If it's driven by a belt then it's pulley. I can't fault anyone for using that term that is almost universally used regardless of if it's technically correct or not.
Well anyway with that aside this isn't a criticism of your video, you clearly have done careful research here and your explanations for everything are excellent. I just commented in case you wanted some constructive feedback. I am completely open to correction on any of these points also.
I thought you might find it interesting that did some mods to a 7afe head a while back and I was surprised to discover it had literally zero overlap between the cams. This isn't just by eye either, I put a dial indicator on that head when it was on the bench and I can confirm that the intake valves would fully close before the exhaust would open. Before this I didn't think any car engine had that. Oddly enough it had a reasonable amount of lift at a measured 8.34mm for the intake, weird.
I built an AE92 Corolla for Lucky Dog Racing League with an unmodified 4A-FE (ok, I baffled the oil pan and built a cold air intake from PVC pipe, but other than that, unmodified). there is jack shit for power above 5800 RPM, where I set the shift light.
We held off some odd cars through 3rd gear but waved goodbye to their tail lights once pulling into 4th, and the explanation on valve angle effects kind of explains it. glad I didn't convert to the GE head though.
You made me appreciate my 4afe 😅
4AFE owner - mines 568k/30 years driven and still runs smooth, going for the 1 million and another 30 years😄
the only criticism i have (at this moment) would be more clear pronouncing of some words like 'scavenging effect' and 'pent roof'. I had to google for a few minutes before I found what you meant.
this video was very well done, and was a superb learning tool about engines. I really enjoyed it. good clear explanations for some key concepts about engines. thanks a lot for showing us! really looking forward to more engaging content, you have a sub, here!!
Holy cr... Your videos are sooo goooood!
Just flippin' brilliant... sub from just one video.
Great Video. I've got a 4wd car with the 7AFE and the heads are very similar and this has kind of convinced me that a turbo on the existing head is probably smarter than a GE head :-)
It's a Toyota Sprinter Carib - AE115G - really popular in russia :D
@@AlexTrull7a-fe...... everything before the dash is the block, everything after is the head. 7a is the block...... the seventh generation of the A block, 1.8l and a longer stroke than the 4a, so the block is taller. The FE refers to the head, F is the narrow valve angle, E means it's injection. Your 7afe head is the exact same as the 4afe head.
Very educational and clearly explained, thx!
Very interesting video as always. Thank you!
You made it easier for me... Thank You Sir
keep doing it bro, i've learnt so much from you
I had just finished watching your quiz video on the inline 4 and so when I saw this I jumped at the chance to expand my knowledge. I grew up on old school Ford engines primarily the Windsor line so some of this stuff is completely new to me. However the trick with the hammer to get the valve retainers off it's actually a really damn cool trick! Probably wouldn't do something on high performance vehicle but just to pop them out of there that is really awesome!
Awesome vid bro was very informative
This is very interesting, as a slow driver who doesn't rev his engine, I'll take the ' economy ' head thanks.
I wish this video has spanish subs, I have a Levin AE111 with a 4AFE engine, I love it and your video looks really interesting, congratulations.
My congrats for your videos, Very good explanantion and content
You’re the best bro...
Great videos!!!
Cool video bud 👍 Damn I miss my 87 AE86 coupe 😥
Fantastic high-cost videos.
2:44 how is changing the timing of the exhaust cam going to do "the exact opposite" on the intake cam??? Yes, they're locked together, but if you advance the one, it's gonna just advance the other by the same amount, and vice-versa...
How did you miss the pinned comment?
@@d4a the one with merch links?... or you see what I'm saying?
Great video, but I think you switched the cams on the 4age, at least in the beginning. Because you can see the opening for the distributor cap on the right (exhaust side), but the cam with the gear to drive it is on the left (intake side).
Love these engines and love your information on them. I am smarter now! 😀
Listening to you is like listening to a favorite song😊
Sounds back, thanks!
This is the first video I've found from you (subbed around the 15 minute mark, awesome info) I think another good video if you haven't done it already is the subaru fa20 (brz/frs) compared to the fa20t from subarus other models
For the 4AFE it looks like it would be possible to put 4AGE cams. At 0:33 if you look at the FE head intake side you can see a metal insert that look like it could be removed. It would most likely take a little more modding to get them to work, like needing smaller gears.
The inlet camshaft would also need a seal, which would not fit, because the wall is thin, one can't machine out. I am pretty sure that with enough effort it could be done, some milling, and making a seal housing on the lathe, then assembling it to the head... But not just "enlarge the hole".
Btw, according to the video, the 4A-FE head doesn't seem to be to much weaker than the GE, might be worth a try to tune as is, the real devil is in the intake manifold and the ECU, I guess. I have a Carina E by the way.
An other great video! Thanks again!
this channel is so dope
It amuses me at how old cars used rockers and new cars have gone back to this idea I've just changed my cam on my 2ltr pinto from 1971 and personally I much prefer the ease of adjusting valve clearance on rockers than shims.
I do miss my mr2 with the 3sfe engine it was alot more fun to drive than the 3sgte mr2 I also had.
One nit to pick. Valve surface area isn't the important metric. Valve curtain area, the area which is open to flow, is the important metric.
4AGE sound is so uniqe thanks to things you mentionend... :D
Thank you! I now understand why my 4ac pulls harder then the 4age at lower rpm.
What exactly is the valve angle on the 20 valve 4AGE?
Car nerd bliss 😌
If I could suggest topics for this channel, one is capacitive discharge ignition and two, how to adjust variable timing cam gear, both intake and exhaust, as you show in this great video. Thank you.
I did one of those ages ago: ua-cam.com/video/Yv4Ao7WMmS8/v-deo.html
Love u man, appreciate this alot.
I am not going to mess around with my 4AFE cylinder head. But if find it interesting that my car has 114 hp ( not 105) and my brother has 88hp on his 4EFE 1.3 while later they only had 75 for better emission and mileage. I think all of those changes where made by the ECU. So it seems to me that a mapping of the engine could give you extra power without even losening one bolt. ( not much on a non-turbo engine, but still something ).
320 000km corolla 1.6i, 114hp.
If I ever would do anything, I would have a rebuild/full service of the head, and change the piston rings to make it perform as brand new... but it is still a surprisingly strong car in modern traffic at age 29 years.
Well, I def learned something about shim over bucket vs shim under bucket! Learned more about valve angles too. Plus more detail on those 4A heads of course. Excellent, excellent video as always.
Shim under bucket old tech shimless solid buckets are were it's at.... lighter and no Shim issues cause there is none...
New subscriber over here nice vídeo
Love this video
Knowledge and content are top notch but please turn that background music off in future videos
Thank you thank you again I learned a great deal with you
Would tiny, tiny fin like structures on the valve side facing the intake port (machined on the valve disk in a slight spiral maybe?) help with better mixing of air and fuel in the combustion chamber? Help make the charge enter the cylinder in a mixing helping way :) Love your videos! fun and educational!
Check out racing 4age valves from manon racing performance, or even many other aftermarket racing and high performance valves. Many have something extremely similar to what you're describing.
More, more, more...please make more videos!
Can You do a comparison on Economy K series and Performance K series next?
at 1:16...why are the cams backwards in the 4age head? anyone else notice that? the one with the gear should be on the right as it drives the distributor...
Definitely already spotted by Dima Minko :) This is a junk head I just slapped together for the vid, wasn't even paying attention. Yes, the exhaust cam drives the distributor but otherwise it has the same exact specs as the intake cam.