Quick Spool Turbine Housing Flapper Valve - Need help!

[Alky V6]

I got side tracked with having to deal with throwing together a pro light start program for Pinks All Out in Bakersfield. Now we're back to the sportsman tree for the Summit Series Finals in Arizona, and good ol' pre-spooling. Next test and tune is Sept. 25th. I should have some good info to share then.

Pro light start with no pre-spooling netted 145kPa by 6250 rpm. I don't know what the result would have been without help from the boost valve. If I remember right, from testing when I first installed the 91mm, I was getting 145kPa by somewhere over 6700 rpm. That could have been with the old 200 shot also. I'd have to check back over my notes in the Advancement of Fuel Delivery thread.

 

[GDNF2ET]

Any updates on the spool valve advantages ?

 

[Alky V6]

Any updates on the spool valve advantages ?

The spool valve does work well. In one comparison test, 145 kPa was reached 900 rpm lower using the valve over not using it. I would definitely be using it if it wasn't for this new anti lag system I stumbled across. The als won't work with the spool valve, and the als has shown more promise than the spool valve, so the spool valve has been put on the shelf, so to speak.

 

[turbobitt]

Don,

I don't venture far somtimes within this website and just now stumbled upon this post. I have this silly idea of fast-spool idea I've been kicking around in my head for a while.
What about a well placed nozzle aimed at the turbine wheel blade tip that injects high pressure gas to excite the wheel ? My only concerns would be the temp differential and the shock it may have on the hot wheel.
Allan G.

 

[Alky V6]

Don,

I don't venture far somtimes within this website and just now stumbled upon this post. I have this silly idea of fast-spool idea I've been kicking around in my head for a while.
What about a well placed nozzle aimed at the turbine wheel blade tip that injects high pressure gas to excite the wheel ? My only concerns would be the temp differential and the shock it may have on the hot wheel.
Allan G.

That plus the fact that it would be cooling the exhaust temp also. Heat is important for spooling.
I would think that it would take a tremendous pressure and volume of gas released from one nozzle to affectively do what you're proposing. I recall playing around with the bench air gun and the turbine wheel when I was changing the turbine wheel on this 91mm and the air gun was not real affective at spinning the wheel up.

 

[turbobitt]

That plus the fact that it would be cooling the exhaust temp also. Heat is important for spooling.
I would think that it would take a tremendous pressure and volume of gas released from one nozzle to affectively do what you're proposing. I recall playing around with the bench air gun and the turbine wheel when I was changing the turbine wheel on this 91mm and the air gun was not real affective at spinning the wheel up.

Blow gun pressure is weak and does not have the benifit of exhaust gas helping it. Using 1000+ psi over 100+ psi is a big difference. I'm thinking that the energy lose due to cooling would be insignificant. Just a thought anyway...
Next best thing would be to adapt a VGT/VNT exhaust housing to a performace turbo. Nozzle position could be simplified by using stops for a two position set-up(one for quick spool, other for normal operation). I've had the privlage of working with all the major turbo companies version of the VGT/VNT turbo's and surprised that the technology hasn't hit the performance market very well.
Allan G.

 

[Alky V6]

Blow gun pressure is weak and does not have the benifit of exhaust gas helping it. Using 1000+ psi over 100+ psi is a big difference. I'm thinking that the energy lose due to cooling would be insignificant. Just a thought anyway...
Next best thing would be to adapt a VGT/VNT exhaust housing to a performace turbo. Nozzle position could be simplified by using stops for a two position set-up(one for quick spool, other for normal operation). I've had the privlage of working with all the major turbo companies version of the VGT/VNT turbo's and surprised that the technology hasn't hit the performance market very well.
Allan G.

The problem is, what source would you use for a 1,000 psi shot?
I agree, a VNT for racing would be neat. But then, closing the turbine down would increase back pressure that might affect a large turbo cam. Another compromise. And, I know. The spool valve is doing the same thing. Just looking at it from my particular case perspective.

Looking at the hot side only, turbine spooling quickness is basically relative to the size of the turbine wheel/housing combination AND the mass and temperature of the gases flowing through the turbine housing. Eveyone seems to be blind to the gases side variable. When you're playing around with different size turbine wheels and housings to affect a particular spool up characteristic, you're doing so with the mindset that the mass and temperature of the gases that will be flowing through the turbine is a constant.
What if there was a way to reverse that scenario. Pick a turbine wheel/housing combination that would affect the best flow characteristics for the engine at max power level, making that the constant, and making the mass and/or temperature of the gases flowing through the turbine housing the adjustable value, and in the end having a system that wouldn't sacrifice engine power at any rpm level within the anticipated powerband.

 

[Alky V6]

I thought I'd post the results of using the spool valve to somewhat finish this thread.
In my case, the spool valve was good for right at .100 of a second off the 60 foot time. This involved using the spool valve with a traditional nitrous tuneup over using the nitrous by itself without the spool valve.
I no longer use the spool valve, though. I discovered a special quick spooling tuneup involving the nitrous system and methanol that is killed if I try to use the spool valve along with it. Since the new nitrous spooling tuneup is worth .200 of a second off the 60 foot, .100 of a second better than the spool valve with the traditional nitrous tuneup, the spool valve, unfortunately, loses out to the new tuneup.

I would venture to say, that if a turbo that more reasonably matched my engine combination was used, the affect of the spool valve would have been even better.