I have a new vortech install with the 3.12 pully, but am only getting 4psi. What are the possible causes that need to be checked? The obvious is a leak somewhere, but could there be other causes like a leaking surge valve? What should I be checking?

 

Is it possible the boost signal is not routed properlly to the bypass valve?

 

Belt slipping..?

 

4 psi with that pulley is definitely low. I would be willing to bet it is the belt slipping. If you were leaking you would probably heard a loud whistling noise. Have you checked the belt? Who installed it?

 

Are you running an underdrive pulley. If so that's your problem. If not than you have a boost leak or need to tighten your belt some more.

 

+1... or the guage is wrong.

 

does it feel week if not i would try to swap a gauge with someone real quick to see if thats the problem if that not it might want to take it back to who put it on and ask them to check it out,

 

Does the car squeal on startup?

 

Yes, it feels weaker than what I expected, but the belt seems real tight, only about a 1/4" play. No squeeling.

I am taking it to VRT next week for tuning, and have already let them know about the problem. I just wanted to see if there was anything I could check in the mean time.

 

vacuum leak?

 

whats does your vacuum on your boost gauge say

 

I would first check

1- bet slip
2- plenum boost leak ...you may not have a vacuum leak in the penum , but have a boost leak . My crawford plenum didnt have a vacuum leak but would leak boost once above 6 or 7 psi . Only way to check for it is to preasurize the whole system with a air compresser .
3- boost leak somewhere else , pipe , bov

 

I think you jinxed me cause my Z isn't boosting right all of a sudden. I might have put in too much 101 octane though. I cut it with 91 but I might have messed up.

 

sounds like vacuum

 

Haha I got you beat. Mine is boosting 5lbs. Ratz just got a fuel leak fixed and now I see something else leaking in a way different spot. It feels like I have a vacuum leak too but it might be a fuel related problem. So random though.

 

Or Vortech kit is showing 16psi.. Gauge is way off Measured on the dyno at 8psi. First step is make sure your gauge is accurate.

-Mark

 

Imagine how awsome 16lbs on the Vortech would feel. Everything was working fine yesterday. Just my luck

 

On hot days when the belts are very hot . I see 14.9psi before redline

 

jason your running 16lbs? damn thats alot of boost Dont worry im sure youll get it fixed before the weekends over.

 

Yep, that's the first thing is dyno testing on Monday, but if its really making 8psi, I am going to be very dissapointed in the performance. I've got a feeling the boost guage is accurate given its a really good guage, and by the way it feels, starts to pull around 3.5K RPM, then never gets stronger as would be expected with this supercharger.