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Tedor
05-17-2012, 07:15 AM
Have a 91 sc

So I replaced the HG, selfported the heads and changed to headers and built a 2.5" dual to magnaflow resonator (more exhaust to be built). After that I started up and took it for a test run, found out that it was only pushing 8psi with stock pulley. Before I remember having like 10 psi, would this drop be coused by the little better flowing heads and the much better flowing exhaust?

Before I pulled it apart I ran a 10% overdrive on SC and pushed 13psi max, I removed that so that I dont run to lean beacuse of the heads and exhaust I now run.

I have always run 3" CAI. And no more mods than the one mentioned.

Thanks

kenewagner
05-17-2012, 08:06 AM
Have a 91 sc

So I replaced the HG, selfported the heads and changed to headers and built a 2.5" dual to magnaflow resonator (more exhaust to be built). After that I started up and took it for a test run, found out that it was only pushing 8psi with stock pulley. Before I remember having like 10 psi, would this drop be coused by the little better flowing heads and the much better flowing exhaust?

Before I pulled it apart I ran a 10% overdrive on SC and pushed 13psi max, I removed that so that I dont run to lean beacuse of the heads and exhaust I now run.

I have always run 3" CAI. And no more mods than the one mentioned.

Thanks

Sounds very normal to me. You removed some restriction and now you have to up the overdrive to get the boost back up. Even with the boost down due to lower restriction you are likely making more HP than when it was at 10psi. Put the 10% pulley back on and it will give you another boost of HP. Then you will need to start managing the heat from spinning the blower faster or the computer will start pulling timing on the top end

Ken

Tedor
05-17-2012, 04:13 PM
Exactly what I thought, Thanks!

Managing the heat from the blower do you mean bigger IC?

kenewagner
05-17-2012, 04:58 PM
Exactly what I thought, Thanks!

Managing the heat from the blower do you mean bigger IC?

Bigger IC or Alcohol Injection are the main ways to do that

Ken