Page 1 of 1

Pulley tune

Posted: Thu Nov 15, 2007 11:52 pm
by loud
I have the predator u7142 for a 2003 cobra, I am installing a smaller blower pulley and inquiring to see if the pulley tune provided in the predator turns off the WOT boost bypass valve, to prevent the extra boost i am adding from bleeding off. Thanks

RE: Pulley tune

Posted: Fri Nov 16, 2007 2:13 am
by h083221
loud

No it shouldn't do that. The boost bypass valve is really just utilized at lower engine speeds to improve fuel econony and give the air somewhere to go when you let completely off the throttle. It then just recirculates the air in the supercharger. When you are at WOT ... the boost bypass valve will remain closed, and all air goes into the intake ... no recirculation or loss of boost.

Although I do not know exactly what all goes into the tune ... I suspect it is mostly changes in spark and fuel control.

The standard 93 oct power tune will likely add in some more spark advance and put the air/fuel ratio in the "sweet spot" for more power all the way along the power curve.

The 93 oct pulley tune will do the same with the air/fuel ratio ... but it will pull some spark back out to compensate for the extra boost and keep your engine in the safe zone so there is no detonation (knock).

If you have a 91 oct pulley tune option ... it will take out even more timing ... to compensate for the fuel used ... again to stave off detonation.

I hope this helps.

Re: Pulley tune

Posted: Fri Nov 16, 2007 11:59 am
by kmac1
loud wrote:I have the predator u7142 for a 2003 cobra, I am installing a smaller blower pulley and inquiring to see if the pulley tune provided in the predator turns off the WOT boost bypass valve, to prevent the extra boost i am adding from bleeding off. Thanks
The pulley tune will work perfectly for your application and no boost will be bypassed at all during WOT.

Kevin@Diablo