Installed HEI this week. Set timing to 9BTDC. It was hot out, upper 80's when I was driving around. It seemed to have less stall at moderate acceleration than before, but after it got good and warm, behaved much like before, backfiring, stalling in traffic. You can either idle or hit WOT to make it go. And one might think WOT would be a danger. But when you have almost no performance, it's not that bad. I had previously set the timing on the old distributor to 17bTDC and it seemed better. I didn't want to go that high with the nice new HEI system. It even backfired on the interstate. I didn't notice any wobble in the old distributor shaft.
Here's where I stand:
- Old carb, new carb. Backfire when hot.
- Old distributor, new HEI. Backfire when hot.
- No broken springs or obviously sticking valves. Compression low, leak-down test sounds like rings leaking, cylinders 1-4 about the same, #5 worse, #6 twice as worse as 1-4. Tester was low pressure (15 PSI) Harbor Freight model.
It could be that I'm running too rich with the new carb. The paper with the carb claimed jets were OK for this engine. The old carb literally dripped gas when running.
I've checked and see the accelerator pump squirts gas right away, but looking at the Holley website, it looks like there is a whole lot of tuning that can be done on this carb. I was trying to stay away from changing the jets until after the engine gets rebuilt.
I don't know if I'm asking a question or if I'm just talking... :-)
Mark
