ChrisJ951

Hey all. I have an 86 951 with a Vitesse stage II kit with a dual port W/G, widefire headgasket, ported and polished head by lindsey, full 3 inch exhause with no cat. New piston rings, etc..

I wonder what the highest amount of boost I can run on that engine? Right now it is set at 16psi and the car hauls ***, but would like to turn it up a bit.

Thanks,
Chris

Mighty Shilling

well, make sure you monitor the AF ratio... that'll be a start. don't lean it out.

renvagn

I have heard you can run as much as 18 without going crazy.

ChrisJ951

How come companies like Lindsey and Powerhaus say results with "only" 23 psi if it isn't realistic?

Jeremy Himsel

Because 23 psi is realistic on race gas, not pump gas. I have a Vitesse stage 2 and have run 17 psi on 91 octane without an issue. Anything more than that you start to skirt the line with high EGT's.

ChrisJ951

What octane is considered racing fuel?

Royal Tiger

Usually over 100. There was a Sunoco around here that still sold CAM 2 Purple at the pump. That was 104 I believe.