I'm curious about the GT4202R. I've seen claims of 2L motors spooling these bad boys by 5500-5700 RPMs and was wondering what size turbine housing that is used for this? Also, is that with a twin scroll setup or no? Engine/head modifications?

 

I am running a GT4294R (70mm) on a 2.0L. It consistently makes ~32psi at 6000rpm. I am using a Tial vband turbine housing and a Tial 60mm wastegate. The more you turn this turbo up the faster it spools, of course. Its pretty lazy until around 12psi or so but after that it rips like a bike to limiter.

for someone wanting really nice power on good driveability I would definitely recommend the 70mm 42R. Ive seen dyno graphs over laid between 42Rs and T67/ptrim setups on both Hondas and Evos and its not uncommon for the 42R to come on just as well as the 67 but make at least another 100hp easily up top. Ive owned both a 67 powered 2.0L and now a 42R powered 2.0L and the difference in spool is not even noticeable. I have no experience with the GT4202 (74mm) like you asked about however.

HTH

 

Any idea if the Tial housing helped with spool up? What size A/R is the Tial housing that you use? Also, what are the specs on your motor build?

 

I would definitely do a twin scroll for spool. It will hurt a little up top but if you are planning to run this in the street that is the only way I would go. Given this is really a race turbo. The tial housing is smaller than a normal t3 housing and the top end is hurt do to this. The spool on a tial isn't that much better either.

 

Well, car won't be specifically for the street, but I'm not promising that it won't see the street either... The objective is about 1000 hp. And turning 10000 RPMs won't be a problem either.

What I'm really curious about is the AMS 42R kit. What size turbine A/R does that kit use to achieve the 5500-5700 RPM spool up on a 2L and is it a twin scroll or no?

 

do you have any more info on the Tial Housing?? it souinds like a great idea, helping both spool and top end power whislt fitting in a smaller physical space. it seems few people are willing to try it though. what are your opinons compeard to convention housings/twinscroll???

i believe thenormal GT4202's run a 1.01 A/R twin scroll housing.

Cheers

Chris

 

A tial doesn't help top end. It is a smaller housing for fitment. A t4 single scroll housing will make the most power. A T4 twin scroll will make the best spool. A TIAL housing looks nice and you can kinda say is a happy medium. Notice how all the largest drag evo's just switched from twin scroll kits because they wanted more top end since it is just drag only. Spool really means nothing for drag racing.

 

I have no before or after comparison data concerning twin scroll vs the Tial housing. The Tial housing is no way shape or form 'smaller' than a T3 housing. I am using their 1.0a/r housing. Specs on the engine

2.0L 9:1 CP/Crower
BC 288 cams
BC +1 valves
ported head
custom intake manifold / 70mm tbody