Too much boost?
 

I havea Stillen supercharger on a 9lb pulley and just yesterday got my gauges installed in my a pillar gauge pod and while driving last night I saw I was hitting 12lbs of boost. When I got my custom tune I was told my highest whp reading was at 10psi. My questions are is this normal or safe and if I'm hitting more psi than when on the dyno does this mean that I'm getting more hp at the wheels than originally thought?

Is all you have the 9LB pulley? (I would see 9 Sometimes 10 on the 8LB pulley)You might be, IF you are I would say stay out of boost. 12 PSI on the SC is too much for a stock block, Talking from what I have seen not guessing, A few guys including myself motors let go at 12 PSI.

You shouldn't be worried unless your tune is off. Do you have a wideband?

Make sure the boost gauge you installed is accurate as well. Does it sit at 0 when the car is off?

I been running 13PSI for the past month or so with no ill effects. Turbo'd vs SC'd but I would think the SC would be safer because you dont have that torque spike when the boost hits.

Yes I have a autometer boost gauge and innovate wideband. I think the boost gauge is reading properly but I have an appointment with my tune shop (r/t tuning) on Monday so I can have them check to make sure my friend and I did everything correctly. I just thought 12 lbs was a lot higher than expected. And to my other question it would make sense to me that more boost means more power. Safe or not it seems like a safe assumption but if anyone else has an opinion I'd like to hear from you. Thanks

I'm only hitting 12lbs when I'm really on the throttle. Basically maxed out. Only happened twice but it definitely happened

Boost gauge is reading negative 3 at idle. On a side note I have an issue with my idle being set too low. Getting this fixed on Monday

Boost gauge is reading 0 when the car is off

that doesn't mean anything unless you know exactly how much vacuum it should be making. turn the engine off and the car on wait for guage to sweep and it should read 0.

Edit: disregard you ninja posted while i was typing this.

What you want to look out for is going lean...especially under load

12 psi is not that high, read around and you can find people experimenting with 14 on a stock block

Boost numbers arent really a measurement of power levels. Its more about cfm.

Creating more boost psi does not necessarily mean more power...and in certain scenarios could mean less power...for example having cats will make boost numbers read higher than without cats....but take away the cats...cfm goes up, power goes up, and boost psi number will drop


Go let your tuner look at it:tup:

Very good info on a Turbo car tho. The Stilen SC makes less WHP without the stock cats. And experimenting at 14spi doesn't mean it ok for him to see 12PSI. I also not saying its bad "IF" he's not leaning out up top but on the stock Stillen injectors I'm not sure he's not. My duty cycle was to high with my set up so I went with 750's. Some are lucky at 12 PSI and some are not. Just saying on the Stillen SC an 12 PSI stock block is a bit much and I would rather tell him to drop to 9-10. Just me tho cause I wsa an unlucky one

Update: I went to R/T tuning yesterday and they said my autometer boost gauge was reading 2lbs over so this explains it! They also tweaked some things and got me to 440whp from 423! Very happy with that. Also I purchased a set of tanabe gauges that were at sema last year. They've only been in the country for a couple months. Pics coming soon