RAD951

Thanks for the replies guys. I just got back from Orlando, FL on vacations and I haven't had a chance to reply.

I was just brainstorming on this Idea and wanted to see your reactions or opinions. I guess the only safe bet to reduce lag, is to buy a wastegate with a bigger spring rate.

What would be the best spring rate for a delgate wastegate if I am running always at 15 psi of boost or 1 bar? I guess is get a wastegate with a 1bar spring.

Danno

A new wastegate won't reduce turbo-lag. It'll only help you maintain max-boost in the higher-RPMs when exhaust pressure pushes the stock one open (if it has a weak spring). No spring of any stiffness will do anything for turbo-lag because the wastegate's already fully closed anyway in the stock configuration at low-load/low-RPM. The only way to reduce turbo-lag is to get a smaller turbo.

David J. Harrington

[quote]Originally posted by Danno:
<strong>A new wastegate won't reduce turbo-lag. It'll only help you maintain max-boost in the higher-RPMs when exhaust pressure pushes the stock one open (if it has a weak spring).</strong><hr></blockquote>


Unless of course the wastegate is leaking . In that case, a new wastegate could help lag.

RAD, you might be thinking of a supercharged setup like this. This [BOV] is a way that you could "regulate" the pressure from a supercharger, but again, you need MAP. Otherwise, you are metering air that you eventually vent, causing a rich situation.
I agree with the others. The only time that you would shorten would be that of you turbo's operational life, not its lag.

Dave

RAD951

A new wastegate will reduce lag because my stock one has weak spring like all stock wastgates and starts to open up around 4-5 psi of boost. If I would get a wastegate that opened at 1 bar then, the turbo will receive full exhaust gases until it hits 1 bar of boost. My stock wastegate is opening up at 5 psi not 15 psi or close to 15 psi. I have the MBC set at 15 psi or one bar. I know I will have faster spool up times and not to mention 0-60 mph times if the wastegate doesn't open until 15 psi or close to 15 psi, not 5 psi.

Danno

"Unless of course the wastegate is leaking . In that case, a new wastegate could help lag."

Yeah, but if you've got a wastegate that's leaking at low-rpm/low-throttle openings such that it causes lag when you open the throttle, you've got worse problems, like zero boost because any more pressure from the exhaust and it all goes out the tailpipe not through the turbo.