This may be a repost, but I've been searching the forums and haven't really found anything about running less boost then 12.5 other then it is a good chance the gauge is wrong. I am installing a TTR mount and while I am working on my car, was wondering if there is anything I should look for on the supercharger that could cause this.

I know you should be hitting peak boost, especially on cold nights, after about 5500 rpms, but even when I get 6000, it is still at just barley 10 psi.

Please help!

Thanks.

 

whats your mileage on the car roughly ?

 

Does it pull as hard as it did before or is there a noticable diffference ?

 

If your car is low mileage and new, then your engine hasn't broken in all the way and you will only be hitting around 10psi.

 

mileage on my car is 31500. I just started paying attention to the gauge for the past month and noticed that it wasn't hitting its max boost and I take it almost to red line in 2nd and 3rd gear and thought it should of been hitting 12.5 psi lol.

 

You can try repositioning your bypass actuator. It's the black thing on the SC. Either all the way down or all the way up is the most boost. I think its all the way down thats the best but try it to find out.

it's real easy to do. just loosen the 2 bolts holding it to the sc and push it so that it's as far down as it can be. If its in the middle right now then that is def your problem.

 

Okay, thanks for everyones help so far. Will work on the SC tonight and see if that is the problem. Will keep you posted.

Thanks again.

 

I have a friend who just bought an 07 SS and I think he said he was hitting only about 10psi. Now my friends car only has 6,000 miles on it so its fairly new. How long does the breakin take? I mean does the car have to learn or something? I just joined yesterday and am going to be helping him with his car. When I see him again I'll check his bypass actuator. Anyone have a pic of what it looks like on the car? I know nothing about this car.

 

when i was hitting 10psi it was due to the vacuum line getting snagged on the by-pass valve.. quite the issue on many vehicles too

 

I know this is an old thread, but i was wondering if you ever found why you were only getting 10 lbs. of boost. My car has the same problem (10.5 lbs. max) and I have 30,000 miles on it. I've already tried adjusting the bypass actuator both up and down and even adjusting the little set screw, all with no luck. Is there something else i can do or just take it to the dealership?

 

probably a bad boost gauge.
they arent very good quality.

check with a local buddy if he wouldnt mind trying his boost gauge on your car to confirm that its not merely a readout error before you start tearing other stuff apart.

 

I dont know anybody around here who has an ss supercharged. I still have the factory warranty so I might just take it in. I was just looking for a possible quick solution to save me the time (and probably hassle) of a dealer. Any other guesses are welcome... thanx

 

whats your elevation? I know here in edmonton, our gauges are KPa but i believe it works out to like 10.5-11psi is all i really see, but i also have exhaust mods which add power but might make you lose boost.
making more power with less boost is a good thing.
it could be a bad boost gauge too...

 

I'm in Houston, TX, so i'm pretty close to sea level. So i dont know why I shouldn't see 12.5 lbs. of boost. Maybe it is just the boost gauge. It's hard to find time to take it to the dealer though since I work 12 hour days.

 

to adjust the bypass valve .... is it the little hex-shaped screw you adjust or the two bolts holding it there ??????

 

Thats what i had to do to mine , just make sure when adjusting it you dont back the screw off too far cause it can cause a little bind for the butterfly . Adjust it till you feel it has a little stick to it when opening , then add a 1/4 turn or till you feel it open without a hitch or any resistance.

 

to open do you mean clock wise or counter clock wise until theres tension ???