Thumpr cam crap

Timing is advanced or delayed from top dead center to account for rate of burn.
At idle, even with all the exhaust dilution with this cam, 36* is too early.
Somewhere between 17* and 20* is going to be right with that cam in a 318.
Then it will burn a richer mixture at the correct rate to push the pistons down efficiently.

Too bad about the holes in the throttle plates. Probably not needed and may make it harder to get right now. But give it a shot. If you find the blades are too far closed at idle of 700-900 rpm, you'll have to make them smaller.

N1ce2k1llu said

I locked timing at 36 because I keep reading these cams like as much advancing as possible. This will be a weekend cruser. Here's the cam card and link. I have 10 hg for vacuum at 1000rpm.

Click to expand...

With an automagic, set the idle timing so when placed into D, you get the best vac and the rpms drop very little. Start at 17 - engine fully warm. Keep advancing, until there is no more gain. That's enough. Any more is a waste of energy and will result in less power at idle - off-idle.