compound charging

[240cp]

Well i have been doing alot of reading lately and got refreshed on the above topic. I know it has been around for some time and mainly gets inforced with deisels. But i was wondering why compound charging doesnt get seen more in the gas burner world more often? In a nutshell it would basically work the in the same fashion. One turbo(smaller) being fed by a larger one, multiplying boost by over twice the amount of the first.

I by no means have the money to build a engine to handle said boost or the supporting cast to make it happen. But by chance i do have the turbo's to do it. I have a borg warner s472 ext and a borg s248 ext. From what ive gathered those turbos would work great together in compound. Well i was just trying to get a general consinsous on the topic and what everone thought on the idea. I know this is for the super high hp guys but i love the idea and think it would work great. What yall think???

[Joe]

its a waste of money is the bottom line

you can accomplish nearly the same goal/powerband with a properly sized single turbo.

[Cjmartz2k]

http://www.skylinesaustralia.c....html

[Shocker]

its a waste of money is the bottom line

you can accomplish nearly the same goal/powerband with a properly sized single turbo.

Not to call you out or anything here but you cant be serious?

I understand what you are saying accomplish the same goal/power output with one single as opposed to a compound setup. However it will not have the low end response of a properly sized twin compound setup.

A dude over on Supraforums has an AMAZING setup on his z31, the response he gets for the power it makes is just awesome. This type of response makes for a more street friendly car, along with circuit type racing.

Also as Chris just posted 1.6 BAR at 3k... making 350kw? That is just down right nasty.

[wrxratd]

Because the HUGE boost you get is useless unless you've got enough cooling and octane to use it. You're pretty much limited to running e-85 or race gas all the time. (E would be pretty damn cheap though!!) If i were you, i'd look into smaller turbos to get even better response and more reasonable boost level.

[Sil240]

Some Diesels use a Turbo and a Supercharger together.

It's definetly different approach.

But your compressing, compressed air.Intake Temps I'm sure are pretty high, which would be killing performance and causing detonation.

You would def need a nice and big air to water setup.

And like above you wouldn't be thinking about Pump gas. Unless your gonna mix it with Race gas, Toluene or something else.

[wakotow]

With water/methanol injection intake temps would be no problem.

You wouldn't have to run huge amounts of boost just because they're compounded, the real advantage would be the range of that boost. Using a stock size turbo and for example an HX50 or similar, you could constantly run both turbos in the sweet spot of their maps anywhere between 15 and 75 psi.

You'd have the same detonation issues if you ran a single turbo at too high of a pressure without race gas.

[240cp]

Agreed with above. With methonol you could keep temps below that of normal intercooling and run insane boost. I just wish i had the loot to build a motor that could handle it all. Somebody with the cash take a dive and build something like this for us to go ohhh and ahhhh over.

But seriously this, to me is the solution for the peaky output of the big singles and keep that low end response that everyone desires.

[RustspecS13]

Ive been tempted to try it with my RB20 and its stock turbo, after the ex wheel was replaced with a steel one or similar turbo. And a HX35 or HX40.

My friend has a dodge diesel that has compound turbos and its a very simple setup and works amazingly well. Enough to peg 1400WTQ and ~750WHP, which of course destroyed his stock auto transmission.

I'm trying to get his HX35 that's in fantastic shape and I guess is modded with a BB center section.

Or I was thinking about the holset with VGT...might be simpler.

~Alex