Sc400 / Gs400 Turbo Kit
I am hoping someone has a handle on what exactly needs to be done to the intake manifold so I can get one fabricated if necessary.
Any estimates on the amount of labor and the cost of the whole modification?
Lets keep the momentum rolling....
Garrett (M10) T3 Turbo
The compressor AR is 0.42 and the turbine AR is 0.48
I know these are small but would they be sufficient together to provide enough boost for 450rwhp on the SC400? They seem like they would spool up mighty fast.
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Also, I was quoted $800-1200 to make a custom exhaust manfold and 2 to 3 weeks. Is this a good price and time frame?
and...
One shop told me they would consider doing a turbo kit but they need to have enough people show some real interest. We would have to prove that enough people would really buy the kit and not back down.
Would the following turbos work or would they be too small?
Garrett (M10) T3 Turbo
The compressor AR is 0.42 and the turbine AR is 0.48
I know these are small but would they be sufficient together to provide enough boost for 450rwhp on the SC400? They seem like they would spool up mighty fast.
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Also, I was quoted $800-1200 to make a custom exhaust manfold and 2 to 3 weeks. Is this a good price and time frame?
and...
One shop told me they would consider doing a turbo kit but they need to have enough people show some real interest. We would have to prove that enough people would really buy the kit and not back down.
what would the price range be?
Celebrating Lexus & Toyota from Around the Globe
all in all not a bad deal; and whoever can get you manifolds for $800-$1200 (remember you need two); is a good deal; i'd run with it

two T3s will be enough for around 600rwhp with sufficient boost
all in all not a bad deal; and whoever can get you manifolds for $800-$1200 (remember you need two);
Do you think the stock exhaust manifold could be used for low boost(10PSI) applications with just modification so that a turbo could fit at the end? I mean SRT is supercharging Lexus cars with stock manifolds and getting 400RWHP. And...
With that in mind would we really have to fabricate an intake manifold or is the stock one also sufficient for low boost?
two T3s will be enough for around 600rwhp with sufficient boost
The compressor AR is 0.42 and the turbine AR is 0.48
This particular model of T3 can do 600 as a pair?!!! That would be awesome.
Yes this is for the pair. However...
Do you think the stock exhaust manifold could be used for low boost(10PSI) applications with just modification so that a turbo could fit at the end? I mean SRT is supercharging Lexus cars with stock manifolds and getting 400RWHP. And...
With that in mind would we really have to fabricate an intake manifold or is the stock one also sufficient for low boost?
600RWHP is more than I am looking for. I was hoping for 400-450. With the specs on that turbo I mentioned
The compressor AR is 0.42 and the turbine AR is 0.48
This particular model of T3 can do 600 as a pair?!!! That would be awesome.
450rwhp should be easily attainable with 10-12psi; and that is most likely doable on stock compression provided there's a little tuning involved
as for ECU reprogramming; i've stated having a preprogrammed greddy emanage to plug up would work wonders; i know people that can get access to the software; its just the issue of tuning the car the first time and distributing the maps; and the greddy emanage has the most features for anything in its class... you can run bigger injectors, additional injectors, and timing control and fuel control all at the same time
the EASIEST thing to do would be to pick up a MSD boost timing master controller... it retards timing 1-3 degrees per pound of boost... and get 2 additional injectors to plug into the pipe right before the throttle body and program them to come on at like 2-3psi of boost; and an upgraded fuel pump (i'm not sure how much it can take)
but yeah; twin T3s or even ported T28s with T3 wheels in them would make plenty of power...
twin T3s would spool around 2000rpms most likely; REALLY REALLY fast... the powerband would be enormous; it would make many big V8 boys envious... the good thing about the T3s is that they allow you a lot of headroom when you wanna make some SERIOUS power. the good thing about the T28s is they are cheaper; and they can still make decent power
and remember; this is all on stock top-end; stock heads/cams, etc... there's no telling what a porting job and some longer duration/lift cams would do... prolly some crazy numbers
1000 rwhp would be hella easier with this motor than the 2jz as far as mods go; its just not gonna be as easy to attain the parts and afford it all

and stock manifolds won't work i don't think; welding a flange onto a manifold is not a good idea; it will end up leaking
getting a set of custom made ones is a much better idea; plus the custom ones can be set up to flow hella more air
this is my idea:
twin T3s; i'll go check out the A/Rs later
twin sidemounts ICs from a SupraTT
custom manifolds as said above
custom intercooler piping
twin BOVs or one single depending on the IC pipe routing
MSD BTM - or emanage
AIC + 2 550 injectors - or emanage to run 6 550 primaries
walboro 255lph fuel pump
twin 3" downpipes that have a downsize flange to bolt to the stock cats
here's where the problem lies:
your limit will be about 10-12psi at the most on pump gas; prolly around 16-18psi on race gas
the tranny won't hold much more than 450rwhp
you'll need a better torque converter
a limited slip will be needed or you're gonna spin like the dickens
and there's the wastegate issue... should a universal manifold be made with twin external wastegates so people that want to upgrade to big turbos like T3/T4s don't have to get custom manifolds made again? or use normal manifolds and utilize the internals that come with the T3s
with twin T3s you won't have to worry about overboosting; but twin T3/T4s might cause a problem...
i think the Supras running the HKS GT2835 twins use internal wastegates and make 700rwhp; so i dunno
Last edited by Bean; May 3, 2002 at 09:49 AM.
His exhaust header has some flexible portions leading to the turbo,and the turbo isn't supported with the manifold.Same with the wastegate installation.
Would some stock Mitsubishi turbos work,I wonder,with a block off plate on the portion of the header that the wastegate would be mounted on higher hp setups?
Those turbos are good for 280hp on the 2 liter,4 cyl. that they came on,at around 14psi.
Any boosted motor will need some additional timing control at anything over 6psi.Heat will rise exponentially at boost levels above 7psi.
Staying at a low boost may be appealing for a very reliability-oriented owner who's willing to live with 380hp,or so.This would allow the use of an additional injector controller,such as the one made by SDS,and keep the ECU totally stock.
Option A...
Flex tubing, on my car? I don't think so, especially not feeding a turbo.







