i have the greddy turbo kit on a c5 engine and wanted to upper boost to around 10 psi ,
my question is y do i have a peak boost at 5000 rpm(10 psi) then goes down at about 8 psi at hight rpm

 

im trying to understand the c5 engine, you mean corvette engine?

cause if that the case the greddy turbo is running out of breath

 

hes talking about the B18C5.. The C5 corvette engine is an LS1..

 

my b18c1 greddy kit had the same problem. nothing a properly tuned boost controller can't cure. i bought the HKS EVC IV used and it works great so far. it has a learning function which learns the boost curve and then attempts to optimize it. it really helped a lot with the boost fall-off like you are experiencing.


[Modified by downpipe, 12:35 AM 11/27/2001]

 

HAHAHA! good one!

 

thx downpipe

 

i got your im. the wastegate dump tube, i think that's what its callled...i think its bent because it has to clear the ac compressor. if you have no ac, i'm sure you could have something made which flows better. as far as the boost controllers go, i thikn you need something with fuzzy logic that'll alter the boost curve or maybe an AVC-R where you could increase the boost duty cycle for the upper rpms. i still run the dump tube but i have a 3" dowmpipe, cponverter, and exhaust. still hodl boost nice and stable.