HiPSI

iTrader: (2)

I'd imagine the downpipe would definitely need to be shortened since the turbine housing will now sit much lower.

I tried emailing them to see if I could get a discount for trying one out .

spoolxexo

iTrader: (4)

Very cool. I wonder how a typical 30R or 35R would work with the QSV?

stockhatch

iTrader: (12)

I wonder how they control boost creep with such a small gate and port. I guess they don't run below 16-17psi though, so it is probably a non-issue.

99SC42

iTrader: (44)

^It will spool really fast like the factory twins, the only difference it hit harder and stay little longer.

99SC42

iTrader: (44)

And you will need some kind of standalone to control when the valve opens and closes.

spoolxexo

iTrader: (4)

I'm sure a simple Manual boost controller would do the same thing.

99SC42

iTrader: (44)

You need a hobbs switch, and mac valve if you are on piggypack and just the mac valve if you standalone.
Not saying that it wont work with a stock ecu but majority of the people that made great power band with it were on on Ems..

stockhatch

iTrader: (12)

Cant you just feed it a signal for the desired opening pressure via a MBC as suggested? All the valve does is open at a defined boost pressure right? Or do people open it at different times based on gear, speed, etc?

99SC42

iTrader: (44)

This is what am talking about

stockhatch

iTrader: (12)

Right, but why do you need all that is what I am curious about.

Ali SC3

iTrader: (10)

You don't need all that there are lots of ways to do it, that MAC valve is basically a boost control valve, same as used by the aem. U need a controller like the EMS or the hobbs switch thing To drive that specific valve. a manual controller may work, but if you have a standalone the MAC valves are better because you can tune it to open up under diff parameters in the aem instead of 1 static setting, like gear, speed, rpm, etc, basically all the ways you can control boost with a standalone. Those valves can be had on eBay very cheap. They are standard industrial air valves.

stockhatch

iTrader: (12)

Thanks Ali. I did some digging, and it seems that they recommend the hobbs/switching valve setup because it can open the gate much faster and more fully than a straight mbc signal.

I found a thread on SF where a guy used a mbc, and it worked, but the modulation was slow, and the valve had to start opening early in order to be fully open by the desired set point. This lowered the efficiency of the valve, and though it did work to a point, the hobbs setup worked better for him.

I guess that answers my question though. You CAN use an MBC, but you wont realize the full potential of the valve.

HiPSI

iTrader: (2)

That makes sense, think about how an mbc works, it's just a bleeder valve. This will make the wastegate or QSV valve in this case slowly open until the desired boost pressure is met. Where as an electronic boost controller will snap open at the desired boost pressure allowing for boost to climb much quicker with the valve being closed until the exact point you want it to snap open.

spoolxexo

iTrader: (4)

That's what I was thinking all along.

Hobbs switches are ancient anyways.

I'm sure that if you used a turnbuckle setup on the QSV flapper arm, you could get that extra modulation to open or close the valve more.

Besides, I've never seen an electronic valve get the turbo spooling as quick as a good MBC. Most of them hold shut until the desired pressure is met, then it bleeds off.

Like the good turbo XS valve with the coarse and fine adjustments.

This QSV business is getting interesting.

TURBO819

iTrader: (5)

Sound Performance QSV PTE6265 Billet Cast Manifold with Automatic Transmission Video.

http://www.youtube.com/watch?v=mRzBf...layer_embedded