Hello all

Here's the situation:

My Master Scion tech did a TON of work on a '96 Supra TT a while back, and one of the things that happened was a complete turbo swap. Thing is, there was nothing wrong with the turbos (just everything else, it seems. Customer bought Supra on eBay, and when she got it, it had a drag racing shop's sticker on the back of it. Ultimately, she needed a new short block, tranny, turbos, etc. The only thing that wasn't swapped was the rear end, really. Anyhow...)

So, we've got these two turbos sitting on his toolbox, and I got the brainstorm the other day to maybe use one of them on our new demo tC. I know that in the Supra, one of the turbos was spooled up at low RPM and delivering boost for low speed driving. Once you hit 4500-5000, the other turbo spooled up, and at wide open throttle, both turbos were running at full boost.

The turbos have integrated waste gates, but no blow off valves. It would not be too difficult to rig up oil and water lines, and I was thinking that an intercooler might be a smart thing to add as well. We have a machine shop and the ability to bend pipes here, so we could design our own lines and exhaust. I also know that ZPI makes a turbo manifold that should accept any turbo assembly.

Here's the thought: It seems that in order to get this to work, we'd need a new manifold, new intake, intercooler, new plumbing, and POTENTIALLY an ECU controller. (Will the ECU adapt itself, or are there more issues that will arise?)

I've done many searches on here for Supra and turbo and whatnot, but I haven't seen any threads where someone has tried to adapt this particular turbo assembly to a Scion tC. The car is an 07 Manual.

I appreciate any constructive input on this, and would like to know if we might be creating more problems than it is worth to do.

Thanks in advance.

 

Good luck finding a exhaust manifold that will fit an 07.

 

You should definitely get that ECU firsthand so that a professional can adjust it properly because those turbos are not designed for our car and nobody has done this yet, so i doubt it could run without some tuning and management. And you'll have to get a custom manifold for it because nobody makes one yet for the 07...interested in seeing the result though if this is done properly. These are the stock turbos off the supra?

 

Plus with that turbo you will definately need larger injectors. I think they made some bigger than 550cc you may want to think about in order to supply adequate fuel and proper tuning!

 

Yep - stock Supra turbos. From a '96. I'm liking the adice so far, especially the stuff about the manifold. We can make our own manifold here at the shop if need be. We have the technology. We can rebuild him. ;)

 

550s should be more then adaquet for it. the supra runs 440s stock.

 

not to sure but with the displacement difference between the tC and supra, isnt it hard to compare how fast the turbo will spool? There are alot of gases coming out of a supra to help that thing spool quick. The 2.4 might not be able to handle it.

I personally dont know and am just throwing it out there for you to look into.

 

I figured that since one of the turbos spools up with low pressure anyhow, it might the better one to use. That 2.4L is a pretty big engine, and shouldn't have much trouble getting that turbo spinning.

I'm not looking for 15lbs of boost, but somewhere in the 5.5-8 range. That should be pretty fun, AND not grenade the motor.

Keep the advice coming!

 

wow..this would be sick... watching for any other updates...

 

whats the difference between the 05/06 and the 07 manifolds?

 

yeah i thought the manifolds were the same. except 07s arch a bit more but other than that the mating surface is the same...

 

what size turbo comes in a stock 96 Supra TT?

 

I say use the stock small turbo, get some rc 550's, a tune and have fun fabing it up. I'd run at least 8 pounds to that engine, several people are daily driven at 10.5 pounds and no problems.

good luck, keep us updated.

 

The Supra was only a 3.0, so there is not much a difference from 2.4-3.0 that it would make lag an issue.

 

sounds like a lot of work but it would be worth it. good luck.

 

the 07 and 05-06 tC maniflolds are the same, the only difference is the MAF sensor which is a little smaller on the 07, but you can make an adapter plate so that it will fit on any intake/piping.

also, if he is going full custom on the piping other than the maniflod you should be perfectly fine, since i assume you will make your own MAF mount.

also.. on the turbo you are gonna use, you stated that it was used for boost at low speed driving..what will happen when you hit a higher rpm?

because you said the turbo's would only act together at WOT.. so i assume the turbo would have some difficulties spooling while its at 4-5k right?

 

To clear things up...

tC Manifolds:
The new 07 manifolds are slightly different than previous models and do arc up more.

Supra Turbo Specs:
The Supra TTs are of two different types. Japanese TTs use 2 CT20A turbos, with ceramic exhaust wheels. They only have a .42 AR so if you use one of those on our tC it would acutally be too small to make any top end power, but it will make good low rpm TQ. The turbine is a 60/48mm (inducer/exducer) and the compressor is a 62/39mm(inducer/exducer. The export Supra TTs run a slightly larger turbo. The AR is a .53. The turbo model is a CT12B and uses a steel exhaust turbine instead. The inducers and exducers are actually a little smaller. Turbine is 52/44mm(inducer/exducer) and the compressor is 58/39(inducer/excducer).

Supra Fuel injectors:

Supras from Japan use high impedance 430cc injectors. Export Supras use low impedance 540cc injectors. JDM Supras also use MAP systems, while export Supras run MAF.

The Verdict:

The Supra turbo will work, but will not make more than 230whp at 7.5-8psi according to my calculations. The turbo will however make great low end torque and spool VERY quickly. Like I said earlier though, do NOT expect to make any high end HP numbers. If you want it only for a daily driver, without racing in mind, then yes it'll work ok. I wouldn't go this route if you plan on taking it to the track often. The Supra turbos are sequential on a Supra. On your single turbo application this 5000rpm shift wont be occuring. What I suggest doing is having the flapper welded shut on the actuator and running a Tial 38mm external wastegate. This will help to properly regulate boost.


Good look with your project though! I love seeing new things on the market. If I can be of any other assistance please let me know.

-Joe

 

$$$$$...how much do you have for this project?

 

It sounds like a bit since it's going to be a demo car for a dealership.

I got an idea. Get a slimmer aluminum radiator, the battery, and use both turbos. What a way to demo a car: do something that's never been done before to that car. C'mon, I dare ya.

 

230 whp sounds like a VERY usable number for daily driving. No tracking out here. I've added too much weight in custom stereo stuff to be a usable track car, anyhow.

Since the only real difference between the 06 and 07 manifold is the arc, do we all think that the ZPI DIY turbo manifold will mount OK on the block? From what I've read, the block of the tC motor has NOT been changed.

The more I read on this, the more excited I am getting about doing it.