Ok first let me say Im being cheap and what some thoughts on this. I have a set of twins off my 2jz supra motor and wondered what people think about using them on my s5 13b. let me say the motor is stock. and Im not really looking to make crazy power I was hoping for about 375 hp. The turbos have .48 ar housings and flow about 20lbs a minute. equivalant to a t3-40 trim. they are small and was planning on running one per rotor. Any turbo guys please let me know if this will work and if its even worth the fab time. Wanting something different with good spool time and i already have all this stuff laying around.

 

they are too small for a rotary. rotary's need larger a/r hotsides than normal cars.

I just built a single t4 divided steup with a t04b 1.15ar hot .50ar cold and it makes positive boost at 2900rpm and reaches 10psi by 3500rpm.

you can easily make 375rwhp with a mild ported motor and a t04e with a stand alone, there are also the bnr hybrid s5 turbo's they seem to work very well, but i would reccomend getting away from the stock manifolds.

 

Supra twins are actually very big for stock twins.



http://fc3spro.com/TECH/TURBO/tmodels.html . I don't know the exact measurements on the FD's HT12's but I think the Supras are equal or maybe even bigger. Compare the Supra CT-12's to the stock turbos on a 300zx (some kind of T25), a 3000GT (TD04-9B), or BMW 335 (TD03-10T) and you'll see they're a lot bigger.

But none of that matters because you will have to fabricate a custom manifold and oil lines which isn't worth it. It's definitely not going to be cheap.

 

That part is actually cheap for me since I have acess to laser tables for all my flanges. so cost is still minimal just dont know if They would overspool, surge or if the .48 ar housings would be to small.

 

I don't think anyone here can answer that with much certainty. Your guess is as good as mine. Worst case scenario, you have to run a cat or something else to restrict the exhaust enough that it won't overboost. I think you should go for it if you truly know what you're getting into. Don't listen to internet naysayers. Sometimes you just want to do something different, as long as the time and money involved isn't outrageous.

Oh and could you post some pics of the CT12 assembly? I've never seen any photos of them although I've seen the diagrams in the Mk IV service manual. Does each turbo have its own wastegate or is there a common wastegate?

 

only one has a wastegate like ours. and the sequential is operated differently the primary has the wastegate the secondary has a butterfly valve post turbine that blocks exhaust flow till it comes on-line whenever that is not sure. i have a set sitting in the next room if ya really want that pic. they are way better designed than mazdas pretty beefy too. they are just like two completly seperate turbos just on the same manifold for sequential use. once off the manifold which is also pretty trick picture a cummins manifold with flex bellows and all thats it, they are only stuck together by the y-flange on the turbine exits.

ahh hell let me get some pics

z

 

 

Ive seperated mine from the center housing so each unit has a wastegate. Normally in sequentail mode they have a prewastegate that opens and closes to spool one of the turbos faster. Think Im going to try wont cost me anything for the flanges and I have the some schedule 40 bends laying around so will give it a try unless someone really has some good knowledge on these turbos

 

Are you going to fab a Y pipe right off the compressor outlets to combine the charge air? That's what they have from the factory don't they, before the air enters a side-mount intercooler? On the 3000GT and 300zx there are two separate intercoolers. The 3000GT has a Y pipe right before the throttlebody, while the 300zx has two separate throttlebodies and MAF sensors.

Making a manifold won't be too hard as long as you can get everything to fit. It's just two runners. Are you going to run true dual exhaust?

 

True dual exhaust and havent decided if I will y pipe or run 2 charge pipes into the same intercooler. Have to see what room allows