10% OD question with exhaust

SK_BlownThunder

Registered User
Okay, I finally have my dad convinced that we are going to change the resonator and install downtubes where the cats used to be, for just a start. I figured being the entire front part of the exhaust is off of my 90 5-speed SC while I am doing the transmission, it was time to look into doing something rather than wasting my time installing the factory exhaust again when I put everything back together.

I will be upgrading to downtubes and a dual 2.25" in and single 3" outlet Magnaflow resonator/muffler, and keeping the factory piping in from there back. With this being the ONLY upgrade to my entire car, is it going to be safe to run a 10% overdrive pulley, or would it even make a difference yet?

Thanks in advance,

Brett
 
I have this exact same setup right now, and have been running a 10% OD with no problems so far. The sound will be semi-loud, and i noticed that i dropped boost about 2 psi down from the same 10% OD on a stock exhaust. With stock, on my other SC at 10% OD I was at 16 psi. Mine right now is at 14 psi max with the SCP downtubes and cats going into a 3" out the back magnaflow, welded into a 2.5" pipe leading into the stock mufflers. It helped top end somewhat, but it also maintains a balance on the low end response. This setup is good if you have no intentions of making a high hp monster, like 400 at the wheels or something. It's good for around 300 at the wheels, imo.

if you are worried about blowing HG's, it would be in your interest to solve any cooling problems you might have, and tune out any detonation issues- this has more influence on the headgaskets than that exhaust.
 
Oh, and make sure they install that exhaust right. They did a sh**ty job on mine, and i had to basically redo the bolts, and tighten the thing up myself. make sure they really seal up the downtube at the header flange or it will sound like a piece of junk. trust me.. i know this.
 
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