compound turbos?
 

alright so pretty much i was at the local toyota dealer and i got to see a supra with compound turbo setup

pretty much it was like a twin turbo kit but it works like a single turbo but it offers 0 lag because you have one super small turbo that spools up for great low end but when it reaches a certain boost level, a wastegate will divert as much exhaust gases to the bigger turbo which would have spooled up by then

this video explains it better then i can but i was wondering how possible would it be to do something like that on the 370z?

http://www.youtube.com/watch?v=y-Me6yWApzY

I would think you'd run into some plumbing and packaging issues. Maybe a mid mount and a rear mount turbo?

Guys do it on the Diesel trucks all the time. From what I read the lag on a twin turbo setup is next to none anyways. You would have so much more piping and have parasitic losses from all the bends and length.

From a packaging standpoint, it may be easier to run a supercharger and a turbo instead. It's been done on other cars. I don't see why it wouldn't work on the Z with a large enough wad of cash. I'm not sure it would end up being worth the effort and cost at the end of it. Someone with too much money or insane fab skills needs to give it a shot.

while the twin turbo kits offer good spool time, isnt twin turbo kits only good for low and mid power?
from what i understand a big single is good for mid and top end and a small single is good for low end so wouldnt a compound turbo setup offer the benefits of both?

i understand there is going to be some power loss because of restricted flow but wouldnt the power from boost make up for the lack of exhaust flow?

i saw something like this on a 350z, it had the stillen roots blower and the STS rear mounted turbo kit

You also have to remember that its not so much boost as it is flow. A awesome flowing truck at say 30PSI can produce just as much HP as 60PSI, boost numbers does not necessarily mean power. Also with compound turbos (where one is not a VVT turbo) I could see issues with lag being caused from the small turbo having to get the larger turbo going. On Diesel trucks the vains in the smaller turbo can be controlled and thus you have much more control over the system.

I am just speaking from a truck standpoint since that is what I know, but I cant see it being much different for cars. If you want a sweet system put a supercharger on the car with twin turbos. You would have to figure out valving such that the supercharger is used in the lower rpms and then it gives way to the turbos. Again it comes down to room for piping.

Here is a picture of the turbo/supercharger setup in one of Gale Banks boats. Someone figure out how to make this work on our cars. haha.

http://assets.bankspower.com/friday_...o_engine4a.jpg

I was just typing this. Even the wording was eerily similar.

No. Even with a smallish .64 gt28, there's a dramatic power increase all the way up to redline. It's all in the turbo sizing. You could get a smaller single turbo and see the same kinds of spool times you see with twin kits. You could get two larger twins that have the same amount of lag as a single.


This would be awesome. Have the turbos feed a roots blower.

Is that a diesel?

Yes its a Chevy Duramax Engine. :D

Well technically its a Isuzu Engine, haha

Sweet Jesus. I want one. I have no use for it, but that's just a pretty engine to look at. I'll make it into my coffee table. Might have to reinforce the floor a bit.

Lol but why?

You would need to have a serious built motor to even think about something like that. It would cost less to build and stroke the motor to reduce spool time than try and fab up something like that.

Yeah, I did this with my 350z. Powerlab kit feeding the stillen.

a compound setup is a turbo & supercharged engine, 2 turbos is still just called a twin turbo

New hood, clutch-type engagement for the roots blower, A2W IC.

And a boatload of money to fab it all up...

Uh, pics?

OP i think you mean sequential configuration..... no?

No, watch the video


The small turbo pipes air into the larger turbo

Wrong and wrong.

Most people in the FI community refer to a twin turbo as a set of identical turbos (i.e. twins) feeding off two different banks of a V-platform motor.

There is also a sequential turbo setup (e.g. OEM Supra), that has two different sized turbos in sequence rather than in parallel. The compound turbo setup is similar, but the piping is a bit different based on what I have seen. Similar concept and goals, though.

Then there is what is commonly referred to as twin-charging, which is a supercharger + a turbo.

ive been in that 300zx its a friend of mine, and its a really nice setup but to be honest its not really worth the money and effort IMO. it worked out for him because he made it but that is a 15k kit to replicate and after playing with it with larger turbos it was still quite laggy. It was deadly with a smaller turbo setup but its still spin city and i think gains can be achieved with a well designed conv. twin turbo kit.

Here is the link to my second dyno session of my 350z with a GT35R feeding the stillen roots. Full torque by 3500 rpms. Sound is indescribeable. Driveability is awesome. Throttle response of a big v8 and then put you in your seat turbo rush.

This is on only 4.5lbs boost at sc and 5 at turbo. Wanted to build the motor and put the 8.5lb sc pulley on and turn up that turbo but I have decided to go to the 370z platform instead of throwing all that money in the 350.

I think with the 8.5lb pulley and a few more pounds feeding it she would have been NASTY!

Twin charged dyno #2 - MY350Z.COM Forums

And....some pics.

http://my350z.com/forum/members/topg...0323-46854.jpg

http://my350z.com/forum/members/topg...0324-46855.jpg

WTF is going on with this setup? So the roots pulls air from atmosphere and then feeds the twins?? That roots is not being fed by the turbos. Which is awesome for heat, but i cant see the w2a under the sc so how does it get cooled? Im so confused and ive set one of these up myself..lol. But a positive displacement wouldnt make sense to not be direct ported. again. WTF!

Also, in series type twin turbo setups, doest the smaller turbo spin WAY out of efficiency by the time the bigger one is pumping out real high end power? There is no way to clutch out or disengage the smaller turbo.Youd think that by 5,000 rpms it would be superheating the air. Anything under a T28 anyway. But youd have to go that small or you might as well go parallell or single.

Looks like the blower compresses air into the inlet of the turbos, then from the turbos into the plenum/WAI.

Heres a article on it.

http://assets.bankspower.com/mag_art...r10_marine.pdf

Hmmm...I bet its not w2a at all. It has an unlimited amount of water so its water to water. Air doesnt cool anything at all. However, I dont see where the single radiator would sit to cool off the end result. Also, its goofy picturing a positive displacement charger charging air through the turbo and system of plumbing. And where is the intake for the plenum if that sc is spit out to the turbos?

Uhhhhhh...:confused: