7afe JDM vs USDM, specifications Options

[playr158]

ok on the topend of the 7afe

the jdm/euro spec is different then the USDM

mostly in valve train but what exactly makes it different and more benificial

[Kwanza26]

Lol... true that I've never driven a a JDM or Euro spec Celica ST, but don't assume I'm just guessing. I'm not the type to base a lot of info on guesses. For one, 90% of the used engines in US are direct from Japan. I've done plenty of 7AFE swaps, majority of which are JDM implants. I have seen the different versions of the intake manifold (2 different USDM version, 1 of which is very similar to the JDM version), have examined the differences between the USDM and JDM accesories, and for all of you who want to believe in some faint hope that "JDM is the SH!T"... go ahead if it really makes you feel better. Physically speaking, they're the same engine.

And again I'll say, the JDM version does NOT have .8mm more lift than the USDM versions. If you think that, you know nothing about camshaft designs. .8 is a LOT of difference. Something believeable would be like 232 degrees duration with 7.1mm lift (4AGZE/4AGE smallport cams) versus 240 degrees duration with 7.56mm lift (bigport 4AGE cams). Considering these are for a more performance oriented engine that revs all the way to 7500 rpms... why would the 7AFE, only able to make power to 6000 some odd rpms, have camshafts somewhat equal to these? Simply based on the torque band, I would guess that 7AFE has no better than 230 degrees duration and 7mm lift on the intake side. Assuming the JDM version has some cool .8mm more lift, that cam is gonna be 7.8mm lift and will be able to make power in the 8000 rpm range... kinda redundant. Lift pushes the power band higher up in the rpm. It'll essentially work against the head design.

As for smog parts... I never said they added power. I simply said EGR does not even come on at WOT, so it doesn't affect the way the engine makes power. What does affect power, is the pre-cat in the exhaust manifold. Those are really the only major emission parts... and I've run without them already... so I'm gonna say although the cat does slightly hurt performance, but it's not a night/day difference. The main thing is, the engines have the same compression, same head, very similar intake manifolds, similar cams (assuming the JDM version has some additional lift), and essentially the same powerband and basically the same ratings.

To close... argument only brings pyrrhic victory. The air of resentment will only worsten. I'd much rather prove through actions than words... but as that seemingly is impossible, believe what you want to believe. I am Done. ;]

[doGGy]

Lol.....

Nothing more to add....

But still, i aint saw the JDM version 7AFE, im only comparing what i saw/felt - USDM 7AFE and Euro spec 94-95 / 96-99 7AFE engine... So

Lol... true that I've never driven a a JDM or Euro spec Celica ST, but don't assume I'm just guessing.  I'm not the type to base a lot of info on guesses.  For one, 90% of the used engines in US are direct from Japan.  I've done plenty of 7AFE swaps, majority of which are JDM implants.  I have seen the different versions of the intake manifold (2 different USDM version, 1 of which is very similar to the JDM version), have examined the differences between the USDM and JDM accesories, and for all of you who want to believe in some faint hope that "JDM is the SH!T"... go ahead if it really makes you feel better.  Physically speaking, they're the same engine. 

And again I'll say, the JDM version does NOT have .8mm more lift than the USDM versions.  If you think that, you know nothing about camshaft designs.  .8 is a LOT of difference.  Something believeable would be like 232 degrees duration with 7.1mm lift (4AGZE/4AGE smallport cams) versus 240 degrees duration with 7.56mm lift (bigport 4AGE cams).  Considering these are for a more performance oriented engine that revs all the way to 7500 rpms... why would the 7AFE, only able to make power to 6000 some odd rpms, have camshafts somewhat equal to these?  Simply based on the torque band, I would guess that 7AFE has no better than 230 degrees duration and 7mm lift on the intake side.  Assuming the JDM version has some cool .8mm more lift, that cam is gonna be 7.8mm lift and will be able to make power in the 8000 rpm range... kinda redundant.  Lift pushes the power band higher up in the rpm.  It'll essentially work against the head design.

As for smog parts... I never said they added power.  I simply said EGR does not even come on at WOT, so it doesn't affect the way the engine makes power.  What does affect power, is the pre-cat in the exhaust manifold.  Those are really the only major emission parts... and I've run without them already... so I'm gonna say although the cat does slightly hurt performance, but it's not a night/day difference.  The main thing is, the engines have the same compression, same head, very similar intake manifolds, similar cams (assuming the JDM version has some additional lift), and essentially the same powerband and basically the same ratings. 

To close... argument only brings pyrrhic victory.  The air of resentment will only worsten.  I'd much rather prove through actions than words... but as that seemingly is impossible, believe what you want to believe.  I am Done.  ;]
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