Quick Spool Valve

[Woody35]

I saw this today and it is a valve basically designed to help dual scroll turbos spool better. Im thinking since the ATT is a dual scroll im pretty sure wouldnt this help the slight lag it has compared to a GM X series turbo? What are your thoughts on it?

 

[ak diesel driver]

are we supposed to search for it?

 

[Woody35]

Yes were not allowed to put up non vendor links.

http://www.competitiondiesel.com/forums/showthread.php?t=106689&highlight=quick+spool+valve
heres some discussion on it

 

[ak diesel driver]

sounds interesting I wish I knew more about turbos.

 

[buddy]

I doubt it helps much, because its the same mass of air and CFM that you put through the turbo, regardless of its velocity. And there is only one wheel. The purpose of the dual housing is to isolate exhaust pulses from banks of exhaust because there is a lot of overlap in some valve trains. I can see it causing issues in cars that come with dual scroll housings for that reason. We dont have that issue, but you will also lose some of that free exhaust flow for better efficiency.

It would likely quiet the engine and exhaust at idle though.

 

[bigchevy89]

yeah but when you get all the exhaust pressure in one side of the turbo housing it will spool much faster. it kind of acts like a vgt housing

 

[schiker]

Interesting idea. I take it the port that closes is also the more inward to center oriented vane direction. Thus the higher velocity flow hits the outer vanes portion of the turbine better. Benefits are the outer area requires more velocity due to tangential surface speed vs rpm of turbine wheel. Outside has a better torque arm to spin the turbine easier.

Initial spooling the mass is less through put is less and this puts a nozzle affect to spin outer portion of the turbine wheel??? Like mentioned above kinda sorta similar to VGT but on the input to the turbine wheel. Or maybe less but anagolous to an internal waste gate.

Cons are once past the spool valve nothing seals the air from expanding internal to the turbine wheel and basically spreading back out to diffuse velocity. Where as a VGT won't allow the diffusing of speed until all the energy is extracted and the air is going down the down pipe. Nothing is free to increase speed of flow will produce higher back pressure to overcome some losses due to nozzle friction.

Now if the double scroll was the same height but pitched or cupped differently and sealed better to be limit slippage between paths then this might improve the nozzle to outside affect. More like a parallel turbo set up Instead of a 2 stage series setup.

It probably is going to have fairly drastically different affects on different turbine wheels/housing fits and flow rates. I don't think its going to be as easy to tune as the VGT technology due to variables of spool designs?????

 

[Woody35]

it is an intersting concept but the few guys selling it want 400-500 bucks. I dont think it is worth it for that price unless you can make your own. One problem i can see happening is on the highway at low rpms you could see some serious backpressure readings that could affect your fuel mileage quite a bit.

 

[bigchevy89]

i think it would be good only for race applications.