C6 15 inch rims 255 70 r 15 tires, like 2.73 rear gears or something low like that.


Ok I just got a vacuum gauge so I can get some type of measurement and that timing tape yu put on the harmonic balancer for better readings.

 

the vacuum holds at around 17.5 psi which according to my book is normal, so it would appear that my problem is merely timing and perhaps light carb tweaking.

I also read that If I have too rich a fuel mixture, running the idle screws all the way in would not kill the engine, so i checked that.

and to ask a lame question, What vacuum port is the vacuum advance supposed to be plugged into? is it the one that has like no vacuum at idle and then increases with rpms, or is it the one thats at like 17.5 at idle and then just jumps when you stab the throttle real quick?

 

ok this is perplexing, I went ahead and installed the softest springs in the kit all the way around for my mechanical advance. I upped my initial timing to like 12 degrees and I still can't see a change in performance and I can't get it to knock at all.

How loud would the knock be? I'm asking because My exhaust consists of only headers with cherry bombs bolted directly do the flange, so you hear alot of popping out of the glass packs and stuff.