ok, I have an 85' LB9 305, really the only mods are intake and exhaust ones. (headers, ported plenum, SLP runners) Im also running stock timing (can't afford to use more than 87 octane) I was just wondering what a good fuel pressure sugestion would be for optimal gas mileage. I am set at 45 psi right now. What is the stock setting? Im kind of thinking closer to 40 psi would be better.

 

IIRC stock is 37/+-3 psi. Mine is actually set to about 34 psi because it was running rather rich. There is no way to just say "set it to this PSI and you well be golden." The only real way to find out what is optimum would be to hook it up to a scanner and find out what is right. That is what I did and it is also how I ended up at 34 psi and mine is a 305 with some modifications to it.

 

is that with or without the vacume line connected?

 

Converted to a 165 and gained 2.5 mpg on my 350. I also gained a couple of miles per gallon (when I still had the 305) by going to a 3" muffler.Of course it looked like a Midas Muffler on the car. It started out with the tail pipe swedging down to 2.5" and the muffle looked like it swedged into 2.25". I cut off all the swedge stuff and put a 3" muffler on the 2.75 pipe (had to do just a little fill to close the gap). I had a real saet of the pants boost from the change and the mileage went up almost 2 mpg.

 

That was driving around and connected.