Guys,

My first Chevy engine build and I seem to have an issue with the timing. After setting the initial timing at 12 degress BTDC (it seems to settle in best here with about 17 lbs. of vacuum) and adjusting the idle at 800 RPM, when I go off idle (rev it with no load) I get some pretty serious popping out the exhaust. Almost sounds like a backfire from the passenger side cylinder bank.

I went through, using a write-up from this board, and lashed all the valves turning the dampener 90 degrees at a time and taking all the slop out of the push-rods + 1/2 turn.

For the record, engine and cam specs are as follows:

Chevrolet Gen 1- 5.7L
Stock bore 4.00
Stock Stroke
Edelbrock RPM intake
Holley Commander 950-700 CFM Fuel Injection
MSD ignition box and billet distributor
Cam: Intake: .420 (at Valve)
Exhaust .443
The cam card is showing "Max Lift" at Intake: 109 ATDC, Duration 204 and Exhaust 117 BTDC and Duration 204.

I've put this engine into a '94 Jeep Wrangler with an SM465/Dana 300 Transmission/Transfer Case combination. It almost seems I have too much timing immediately off idle. The distributor is mechaniocal advance and I'm not sure which springs are in there for timing advance nor do I know what total timing is at a specific RPM.

Any advice on what to look for with this engine. I've built a number of Ford FE blocks over the years and I know they like a lot of timing early. Not sure what this engine/cam combination is looking for, if indeed, that is the issue.

Thanks for any and all help/ideas you guys might have in terms of what to look for or experiment with.

Mike