OK its been a while but I've been working on this for weeks. Figuring my compression ratio again, I think the post above about mine being too low makes sense. However I didn't do anything in the rebuild to change c/r, and the car ran OK before. The only real change was the cam.
Old cam was a Crane 216/228 @ .050, 272/284 duration, 112 deg sep, .454/.480 lift. New cam is 214/224 @ .050, 272/282 duration, 112 deg sep, .442/.465 lift. Is it conceivable this slight change would hinder performance that much? Would it change my dynamic C/R?
Compression checks good on all cylinders. The best vacuum I can pull is 15-16", and thats when the ignition timing is advanced way beyond what it should be. I tried a new carb with metering rods supposedly leaned out for my elevation and had worse performance and flooding. I'm guessing the old carb that came on the car has been jetted way lean just to get it to run.
If the 2801 cam is too tall for the 670 heads, should I be running something more like the 067 or 068 with closer to a .400 lift? High octane isn't available and I'm at 4600 ft elevation. And/or start over with new pistons aiming for 9.0-9.5 c/r and keep the cam and carb I have?
