stock boost

Dbarnhill

Registered User
Anyone know what our cars stock boost psi is? I feel like im running a little on the low side for some reason. I have a 93 auto with a CAI. WoT i get about 7 psi and half to 3/4 throttle gives me about 3 to 5 psi. Is this normal or do i just have too high of expectations for a stock car with a CAI? :confused: I keep feeling like i was getting about 13 or 14 psi on my last 91 auto at WoT

Btw i bought the supercharger from DD when i bought the motor from him and im pretty sure he said checked it for leaks, thats not saying my mechanic who installed the sc and motor didnt do something wrong during installation though
 
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A stock SC typically makes about 12 PSI of boost. If you are only seeing 7 then something isn't right. Your gauge could be off BTW. Thos factory boost gauges aren't always accurate.

More importantly how does the car feel? Does it feel like it has a lot of grunt, especially down low?
 
A stock SC typically makes about 12 PSI of boost. If you are only seeing 7 then something isn't right. Your gauge could be off BTW. Thos factory boost gauges aren't always accurate.

More importantly how does the car feel? Does it feel like it has a lot of grunt, especially down low?

Its funny you say that, im not sure what grunt means but if it means sluggish (i guess would be the closest adjective i could come up with) then yes, especially at low rpm. It just feels like something is holding it back if you get what i mean. Once i break 3500 rpm or so it seems normal
 
That is odd cause with my new belt and to my knowledge stock pulleys (S-port 94/95 blower and MP plenum) I'm back to pegging the gauge at WOT. 2.5-3-2.5" exhaust.
 
Is there somewhere i can hook up an air gauge and run the throttle at the motor to check andsee if the gauge in instrument panel is bad?
 
you will need to use a test gauge of known accuracy and test it against the stock gauge. tee into the boost line and run it into the cabin, then take a drive and compare.
 
Ok ill work on getting an extended air hose and a gauge. Im not sure how the whole vacuum pressure thing works, but will i be able to read the boost accurately with a normal air gauge or do i need something specific?
 
That is real good vacuum at idle. You are pulling some good vacuum. I am thinking you have an ignition issue. What plugs are you running, what is the gap, and how old are your plug wires?
 
Well my mechanic swapped the motor out in it it's been about 3 or 4 weeks now, and while he did so he said he put all new plugs in it. The wires are definately not new though, they look pretty old. As far as how old, I can't say unfortunately because I purchased the car pretty much not knowing anything about it and slapping in a new/used motor, fuel pump assembly, supercharger, spark plugs, motor mounts, CAI, thermostat, and numerous un-related braking parts.
 
Also possible the by pass is not closing properly, alowing air to recirculate. I'm not sure what the best way to verify/check this.

Adam
 
Standard platinum, i didnt ask about the gap because he seemed like he had a hard enough time trying to remember which plugs he used, lol. So that info is N/A right now i guess
 
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