Stock distributor advance springs. What RPM?

[72redbird]

That would probable effect it by 1-2 inches I would think.

 

[HALIFAXHOPS]

What???

MP springs super light which is all in usually by 1200 rpm depending on which advance cam is in it. Really made for the strip. They ping in most street cars.

 

[lewtot184]

i wonder how the OP only gets 10" of vacuum when the engine is probably idling 30 degrees before TDC. what are we missing?

 

[HALIFAXHOPS]

Cam?