interesting single turbo idea..

[gs14racer]

So i was talking to a friend who is in the process of single turboing a sb chevy. Hes running a single 76mm off of one exhaust bank, i thought to my self what a novel idea. He doesnt care about low rpm power he cares about upper midrange/top end performance , plus hes only shooting for about 500 hp, and it was easier on his application just to plumb one side.

This is a good idea for those of us with cramped engine bays as it is. Im just wondering as i have never heard of this done before. What are your guys thoughts on this.

The q45 can be called two 2.2 l 4 cylnders and if you wanted good midrange / top end you can slap on a t3 or t4 67mm turbo and make (i think) pretty decent power there at low boost.

Potential problems i see with this are

1. Un even thermal load between both sides ( however this can be potentially solved by restricting the oppisite side down a bit)2. lack of spool (but hey its a v8 i doubt we will miss much of the low end)3. uneven air flow between banks given that one side will have more back pressure and less scavenging than the other (again could be solved by restricting the n/a exhaust a bit.)4. i really cant think of anything else lol

Anybody know of this being done succesfully on other motors???


Modified by gs14racer at 9:02 AM 8/25/2009

[kingkilburn]

I can't imagine this working very well for engine life or power. Part of what gives V8's there power is good harmonic balance. With a turbo on one side your throwing that out the window.

What I see happening is this The bank with out the turbo Will drag down the turbo side You will either run one bank rich or the other leanI would also think that it would be hell for the bearings.

[elwesso]

would it not be possible to run an exhaust from one side to the other? in other words run the turbo off one bank and just have the other bank connect to the other side... that way you at least have both banks "equalized"

[gs14racer]

possible yes.. due to space constraints it would however be a nightmare to plumb, not to mention the pain of having to run dual wastegates.

The point has been taken, i was just curious because i had never heard of this before lol.

[Chrispy300]

Just run a crossover pipe from the other side. Like on the old Z31's with the VG30ET. That is what I was going to do. Plenty of room for it in the Z32 engine bay anyway.

[gs14racer]

yea but you guys have wider frame rails my headers pretty much sit on the frame rails...

[XJared]

Not a good idea. This goes way beyond just the added back pressure on one side, you would essentially have two different engines to tune, one bank will have no or little back pressure, lower effective compression, lower combustion temps, and lots of blow through at overlap, the other will have much higher back pressure, high effective compression, more reversion on overlap, and higher combustion temps. Just run a Y pipe, but the wastegate right before the turbo so it works for both banks, and be done with it.

[Mettler]

Bite the bullet and go twin turbo! Canadiandrifter240sx has a mint setup, turbos mounted in a mean spot etc... makes the most sense!

[kingkilburn]

You could do a rear mount with a turbo or two in the neighborhood of the rear seat.

[T45]

That would be my suggestion also. You already gutted the rear out, why not cut a little of the floor out to plumb, put them inside, then make a cover for them with ducting. NACA ducts in your rear quarters would look preeetttttty sweeeeeeeet..... hehehe

[gs14racer]

lol you guys are too hardcore for me...

Unfourtunatly on the s14 the gas tank is where the rear seats go, my problem has never been putting the turbos in the rear, the problem is getting the charge pipe, back to the front, past teh headers and the crossmember, plus my car is pretty low.

Ill try and post pics tonight to give you guys an idea of the space im working with.

[T45]

A pipe is a pipe. It doesn't have to be round. Use some rectangular tubing running along the framerail under the car....as a matter of fact, just seal off the framerails and use them to carry your air back up front. hahaha

If you crossed over one exh mani to the other and made a single run to the rear, that would open up space for the return pipe back up front. Notch the xmember, or add a piece of pipe running through it for the charge. So many options, stop being a sissy. lol There is always the open trunk space you could use for the turbo(s) too. I wouldn't think your return piping would have to be 3 inches to the IC but I don't know that much about PSI either. What is the smallest piping you could use?

[T45]

lol you guys are too hardcore for me...

This coming from a guy that gutted his car, used dry ice to remove sound damping, welded in a roll bar, re-wired the car, removed the air ducting, SWAPPED IN AN INFINITI V8, added extensive body mods and runs 315mm tires in the rear....

Unfourtunatly on the s14 the gas tank is where the rear seats go

I'm actually suprised you don't have a fuel cell already.

[darinz]

I run a single T04z with a single 50mm wastegate not problems at all. The turbo is double entry so run one bank to each entry (I know not ideal but OK) and then run a pipe from each bank to the WG. I have a 2" pipe from wastegate to muffler and 3" from turbo and then 4" from there and it is all pretty sweet.IMO you'd be better off to have a very inefficiant log type manifold and find a way to fit a cross over pipe then you get most of the benefits. Mine has 2lbs at 2000rpm so it is worth the effort!

[qsiguy]

.... I wouldn't think your return piping would have to be 3 inches to the IC but I don't know that much about PSI either. What is the smallest piping you could use?

I'm using 2.5" from the rear mounted T70. It stays 2.5" through the IC then just before the MAF steps up to 3.5" through the MAF and up to the plenum. 2.5" tubing will flow a lot of air when under pressure so I doubt the tubing would be the biggest restriction.