[red69ss]

Originally Posted by sloppy_steering

The vaccum advance on my 68 Firebird is to the drivers side. As far as your HEI powersource when I installed mine I went right to the fuse block. I'm no electircal guru, but that's what the instructions said to do. HEI's are apparenlty finicky with their power requirements so I'd start by putting a voltmeter on the BAT terminal and see what it's being provided. Also, how's the gas in your area? Mine's expensive crap.

thanks for the reply, I hooked it straight to the ign. prong on the fuse block yesterday and it wasn't spark knocking last night when I took it for a ride. It was hooked to the old coil wire and was only getting 9 volts so this could have been the issue. As far as our gas it's about $3.70 a gallon here.

Originally Posted by george kujanski

Normally a dist would cause spark knock by having the timing advanced too far or the mech/vac advance curve too high or the wrong curve. Make sure you have at least 12V to the dist BAT terminal and you have no loose connections.




Other possibilities are perhaps your compression is too high, or the timing ring on the crankshaft damper has slipped, and your timing is not what you think it is.

George

I tried retarding the timing and tuning in the vaccum adv., I think I need to change the springs ,it seems to be fully advancing when you start off so I think it needs heavier springs or wieghts. I hope I got the 12v issue resolved. Other than the way it seems to adv. at take off it seems to be running pretty good right now. Unfortunately I don't know the compression on the motor , but I also considered this as a possibility. The guy told me it was a 72 block with 67 gto heads and intake.
I hope the damper has not slipped. thanks for the help.