compound turbo kit?
 

has anyone on the forum had any experience with a compound kit for a 13b? just wondering if anybody had tried this method. I know heat is a problem but maybe somebody has found a solution. thanks!

Explain what a compound turbo kit is please.

thewird

small turbo feeding a big turbo, they do this a lot on diesels.

oh damn that sounds wicked! haha i would think a setup like that would create alot of compressor surge not? how do they deal with that? a BOV in between turbos?

Compounding turbos is more for extreme high boost set ups (40~50 psi and up) and would be a complex, heavy, expensive and inefficient way to make power on a rotary, be it for the street or for a dyno queen. Unless your rich and into novelties or expensive complex ways to accomplish something that can be done simply (IE: properly sized turbo for a 13b).

~Mike.............

Not necessarily for super high boost, but yes it is for higher boost. First designed for diesel engines (the new ford). This design was just used for a turbo setup on a Supra buy a shop(don't remember which one). It works very well. Its a damn good idea acutally, just may not have enough room in our engine bay.

so i'm guessing no one has tried this method. Yeah I was searching around and saw it on the boost logic site. 20 lbs of boost ar 2800rpms lol insane

Yeah it's the latest rave over on the supra forums. This compound turbo kit is built buy Boostlogic. The supra guys are not worrying about turbo lag as much as traction now because this kit produces 20psi of boost by 2800 rpm!
Here is a link: http://boostlogic.com/

I would love to see such a kit for a rotary, I've thought about it before.
the only problem that i could see is that the smaller turbo would choke out the exhaust at higher rpm on a rotary... mabey not though.

Well said.

I was not personally involved with one at our shop, but one was done here at over 100psi... Couldn't deliver enough fuel in the end, even with a -12 hose with no fuel injector attached.. lol

I DEMAND video and pictures or I will commit the rest of my life to you getting banned! :lol:

So GT35R with a small hotside with a GT42R with a big hotside? ~700 rwhp with 20 PSi by ~3500 RPM? Interesting...

Anyone have the schematics of how this works? :)

thewird

if the supra guys can do it. then we can do it lol. i think this seems to be the ideal setup if we can make this work. man if i had the money scenario lol

I'd just like to see how the exhaust and intakes are hooked up lol.

thewird

just go to the boost logic site and look at it. its very confusing to me lol looks crazy man

Basically, the smaller turbo is spooled first then the exhaust is routed to the larger turbo, then to the downpipe. The larger turbo compresses the air a little bit, then it goes directly to the air intake of the smaller turbo compressing it even more.

The idea is that the larger turbo usually cant stuff that much air into the engine at low RPM, the engine just cant take it and the turbo surges unless it has a ported shroud. With a compound setup the smaller turbo compresses the volume so it fits, meaning you can more power at lower RPM. The small turbo cant take in a big volume at low speed so you cant make power, the big turbo can take in a big volume but its not compressed enough. Put them together and its the best of both worlds. Low and high speed power. Im not positive how the wastegate system works exactly, so Im not much help there.

Wouldn't that cause a bad overs-peed situation with the smaller turbo as the big one increase flow rate?

lol. There wasn't any video. It was for tractor pulling. 1150 cubic inch V8. Two T4s, and Two T6s huffin...

the point here is that sure it could work but like ErnieT said there isnt enough room in the engine bay. plus the fact it would way a metric shit ton.

Wow, how much does a metric shit ton weigh?????lol...

Half of a US Spec shit ton?? lol

Like a metric assload, a metric shit ton is exactly 204.62262 pounds more than a shit ton.

thewird

I definatly think that you could fit the setup in our engine compartment, and it wouldn't way very much more than a single setup.

heres a good example of what a compound turbo setup is, to anyone wondering.

http://www.cycloneinjapan.com/upload...urbo_large.jpg

^

Oh please don't give me any ideas... I've spent enough on this damn car...

Questions,

Would map sensor based tuning be enough for this type of setup?

I can't quite tell how the wastegates would work in that picture. I see an internal wastegate on the second turbo but nothing on the first turbo (one with the filter).

Aside from a custom manifold being made, I don't really see how it could cost too much more then a regular single turbo setup? I guess you could count the extra fuel requirements lol.

thewird

precisely...:lol: