Anybody tried putting a non-tvis in AE86?

[BastianAE86]

140hp is "inside" the 20% tuning law...


124hp * 20% = 148,8hp...


So I cant see why it shouldnt be legal...


BUT im not certain! Just what i thought....

[Ivan141]

I have a bigport TVIS ae92 engine in my car at the moment. If you take a look at http://www.whyturbothat.com you'll see an interesting project with a smallport engine in an ae86. The TVIS inlet manifold to smallport head adapter plate is far from ideal for power. This guy welded the inlet to the correct side of the original ae92 manifold and put a supra throttle plate on it, which is relatively easy since you can weld any plate that will work with the supra throttle body to the manifold. With that you'll see some very decent power at the rear wheels.

[Dorito86]

Why do you want to put the smallport in your car? Please give try to put down the pros and cons.

Just bear in mind that bhp figures are VERY unreliable. In reality, difference in power is very little. Practically you can't tell the difference.

I think you'll see it's really not worth it. Recondition the bluetop you have and do another 100.000 revvy kms.

[BastianAE86]

Well, maybe the tvis will stay in... i just figured it was better to start tuning on 140hp instead of 124hp..

The higher starting point, the better...


But maybe ur right.. Maybe its not worth the effort it will take to convert.. DAMN intake... hehe

[jamiemirror]

BastianAE86 Wrote:Well, maybe the tvis will stay in... i just figured it was better to start tuning on 140hp instead of 124hp..

The higher starting point, the better...

Err... no.
If you plan to go over ~180hp - bigport is better :-)
So IMHO if you plan to go forced induction - try bigport head.

[AEsuperG]

sounds like a redtop/bluetop arguement. i say go with the non tvis. better engineered engine. you can hybrid them, too. non tvis block with tvis head. many opinions for you to listen to. best bet for you is to just do what you want. figure out what suits you. i wish i have the time to try all combinations.

i dont really like tvis. i cannot feel a difference in the power band with or without it. you can disconnect tvis. the normal operation is butterfly open with engine off. so disconnect the vacuum to tvis and the butterfly stays open all the time. torque is not lost unless you have an accelerometer built in your head and can tell me different.

i am a believer in air flows better when it is faster...small port. big port uses more air, but slower. velocity versus volume. why do you think toyota engineered the non tvis with smaller ports. maybe they noticed that the big port was overkill for size.

besides i have driven a tvis with bigger cams and a non tvis with bigger cams. i could not tell the difference of who was faster. i never had the chance to race the two against eachother as the two cars were separated by the pacific ocean. but the tvis car was at sea-level. and the non tvis was at 5280ft ABOVE sea level. so i guess its clear which is faster.

[KristianAE86]

jamiemirror Wrote:If you plan to go over ~180hp - bigport is better :-)
So IMHO if you plan to go forced induction - try bigport head.

Not true .
Check all 4-ag engines made by TRD - They always rely on the smallport heads for maxumum power

Kris

[jamiemirror]

KristianAE86 Wrote:

jamiemirror Wrote:If you plan to go over ~180hp - bigport is better :-)
So IMHO if you plan to go forced induction - try bigport head.

Not true .
Check all 4-ag engines made by TRD - They always rely on the smallport heads for maxumum power

Kris

Are you sure ?
http://www.club4ag.com/faq%20and%20tech_...4A-GE.html

Quote:Intake and exhaust ports have been enlarged and polished (intake:67.5mm x 31mm)(exhaust: 36~ 37mmØ ) Combustion chamber capacity » 35cc for 11.5 -to- 1 cr.

I just measured the small ports - they are 50X30mm.
And the big ports are 65X30mm.
So, TRD N2 engine have bigger ports than stock 4AGE bigport engine.

PS: The small port cannot be enlarged from 50 to 67.5 mm due to wall thickness.

[KristianAE86]

jamiemirror Wrote:Are you sure ?
http://www.club4ag.com/faq%20and%20tech_...4A-GE.html

Quote:Intake and exhaust ports have been enlarged and polished (intake:67.5mm x 31mm)(exhaust: 36~ 37mmØ ) Combustion chamber capacity » 35cc for 11.5 -to- 1 cr.

I just measured the small ports - they are 50X30mm.
And the big ports are 65X30mm.
So, TRD N2 engine have bigger ports than stock 4AGE bigport engine.

PS: The small port cannot be enlarged from 50 to 67.5 mm due to wall thickness.

yess...
i was sure - because i read it about a year ago

[Jan Pedersen]

A lot of guys who uses their hachies for rally uses blue top block and pistons with a red top head.

Pros: lighter internals and better flow...