Capt Ken

73 350 4spd. PO installed an 81 crate motor, said he added a slightly more agressive cam. If I remember correctly the timing is set at 8 with the vacuum plugged. Car runs fine, coming up on 2000 since the new motor was installed, figure it's time for a tune up. No MSD. Does the different cam make any difference on the timing? My pubs don't cover the 81 engine. What is the correct timing?

Revi

Read these,

http://www.corvette-restoration.com/...ine_Timing.pdf

http://www.digitalcorvettes.com/foru...ad.php?t=75830

hugie82

You cam can affect timing but it depends on how you would use your vacuum adv but since you don't have any, your only concern is how fast the mechanical advance comes in. In most mild engines you want @36 timing advance in by 3000 rpm. This is a very generic guideline. If you like getting the most out of your engine. I would advise bumping the timing up until it cracks hard or pings when hot under load. Then back off a little. A dial back timing light can tell you if your getting full advance at 3000 rpm if you want to take it to the next level...

Capt Ken

thanks I'll read the links. Vacuum advance works, what I meant is it was plugged/disconnected when setting the timing.