i was doing some pulls last night and at wot im hittin 13-14

 

i hit 17 most on my 2.6, full exaust, built motor, and so forth so where your boost is, i would have to say that is where it shout be, and it also depends on elevation. sorry if it is a repost guys. just trying to help . lol

 

im the same elevation and im hitting 17 with full exhaust and a 2.9 pulley but since your built you are thrown out more hp and tq then i am, well i hope so

 

I dont think your car likes when you got WOT in 5th that low lol

 

Possible cause could be a boost leak, more likly, or a fault piston ring or even a bent valve. Another issue could be a slipping belt, tune, or knock and timing. and so forth

I would say hes got a boost leak a bent valve, blown head gasket, his tune, his supercharger is screwed, belt slippage, to much timing, alot of kr, i dunno, but its worth a try.

wow douple post, kind of lol. sorry guys

 

**** i dont know whats changed on mine but i use to run 2.8 on mine only gm sport cat back and i was running 18 to 20psi ....then i started only doing 15....then i switched back just to stage 2 and now it only does 13 to 15 tops

 

exaust flow, timing, knock, your tune has every thing to do with how much boost you run. If you are built, and have a good compression all the way around and say you have a 2.6 and you run 17lbs, and then you have a guy that has only a catback exaust and he runs a 2.6 but he is running 20lbs of bosot, the guy with the less pounds of boost will have beeter power and torque, because of flow and so forth. A motor (engine is a big pump) (air)... If you have some time of restriction your exaust pressure will rise making stress on the mortor.

 

so i kinda of got thinking about this. when i start in like 1st or low gear. i can hear a whistle when im starting to hit boost like 1-5 pounds......do you guys think the bypass valve is going out/leaking? i have about 40k on it.

 

same thing is happening to me. bump for some help. i already replaced belt, new adj tensioner and hydrolic tensioner, new tensioner pulley..

 

i hit 14-15 psi on my 3.1

 

but i am on a 2.8. something is up right?

 

i only hit 18 with my tvs....it all depends on what mods you have and what is restricting...i havezzp lth w/ 1.75" primaries and 3" full exhaust, port and a polished head which in turn frees up some power...

 

The goal is really how much volume of air you are pushing. PSI is not the end all tell all factor in boosting applications. for example, if your were to do some head work to get some better flow, you would gain power but you actually loose psi. That does not mean you are loosing any boost because you would still be pushing the same volume of air, that just means the psi is not building as high because it is flowing thru your engine better.

 

exactly what i was sayin but with less info lol

 

I'm hitting 15.5psi on my set-up. Mods are in my signature.

It's been fairly warm here - 70°F+ lately.

 

mods are: cobalt addiction header, cobalt addiction 2.5" catted downpipe, cti ota pipe w/ magnaflow muffler, k&n intake, zzp adj tensioner, oem belt, 2.8 pulley, ngk bkr7e's, 80s, E85, trifecta tune.

scan gauge shows 0 knock, iats are around normal range.

 

bumpity bump

 

bump

 

I always boost more in the winter when the air is colder and less in the summer