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twiceblown · 09-27-2005, 05:37 PM

You're right, Chris.
So, assuming -4mm for port size:

(15psi boost)
34mm flapper; Mani pressure: 32psi; Ideal spring: 8.86 PSI
38mm flapper; Mani pressure: 32psi; Ideal spring: 11.39 PSI

(22psi boost)
34mm flapper; mani pressure: 40psi; Ideal spring: 11.08 PSI
38mm flapper; mani pressure: 40psi; Ideal spring: 14.23 PSI

So, how are the guys like IPO, Jack T, and Monet actually boosting 30+PSI without huge amounts of exhaust energy being wasted through the wastegate port? Granted, i don't know what kind of actuators they're using, nor how much spring pressure they've increased by either preload or washers, but i can't imagine anything less than a huge amount of exhaust energy being wasted due to the "blow by".

09-27-2005, 05:37 PM	#42 (permalink)
twiceblown Mmmmm, Boooooost! Join Date: Nov 1999 Location: Disneyheim Hills, CA Drives: 300 yards. Trader Rating: (26)	Re: Measuring stock exhaust restriction You're right, Chris. So, assuming -4mm for port size: (15psi boost) 34mm flapper; Mani pressure: 32psi; Ideal spring: 8.86 PSI 38mm flapper; Mani pressure: 32psi; Ideal spring: 11.39 PSI (22psi boost) 34mm flapper; mani pressure: 40psi; Ideal spring: 11.08 PSI 38mm flapper; mani pressure: 40psi; Ideal spring: 14.23 PSI So, how are the guys like IPO, Jack T, and Monet actually boosting 30+PSI without huge amounts of exhaust energy being wasted through the wastegate port? Granted, i don't know what kind of actuators they're using, nor how much spring pressure they've increased by either preload or washers, but i can't imagine anything less than a huge amount of exhaust energy being wasted due to the "blow by".