What the maximum boost you can run SAFETLY AND RELIABLY on 91 octane? In the interest of engine longivity, I was originally going to boost only 13 psi on the street (with 91 octane) but I'm reading about people on the forum boosting 15+ psi on pump gas with daily cruising. Just curious as to what type of boost levels people are running and their inputs

 

depends on how rich you're running and your ignition timing

 

I am running at least 1 bar on 91. I have been mixing with the trick 101 and running 17-20psi with no problems. Slowly I have been weening my car off the 101 and seeing what happens. Right now I have about a 60/40 mix of 91 and 101 and everything is ok. That is a no less than 11.5:1 A/F, timing at peak torque at 15psi is 12deg with a 10deg split.
So far, so good...