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Tuneup part 2: Running better!

The last session had the car running a little better, but still it would pop and backfire if it was revved up much above idle.  Too rough to risk a drive around the block.

I replaced the plugs, which took me hours because I got to learn what wrench combos work around these headers. After all that, It wouldn’t start. Cranked and cranked…nothing. Put the battery charger on for a while and cranked some more…nothing…KA-BOOM!!! Huge backfire out the mufflers that blew craters in the gravel driveway. Scared the crap out of me, and my wife came running out expecting to see I’d blown myself up with the car.

So I pouted for a while and took care of some electrical jobs (grounds, splice repairs, removing extra wiring) while I thought about it some more. The only thing I changed was the plugs…and they were gapped the same as the old ines at .045. I started checking out the HEI wiring and found a suspect…

Turns out PO did a cheezy splice to the HEI power feed wire. Not only was it a bad splice, it was spliced onto the original resistance wire that used to power the points. It was only getting 7-8 volts…surprised it ran as well as it did.

Ran a nice new 10ga to the firewall plug…

…and now it starts with a touch of the key, and no more popping or backfiring at 1200+ RPM. Smoooth!!!

Haven’t touched the carb aside from spraying it with gumout last weekend. Will probably do the rebuild anyway, but at least now it runs well enough to get it over to the exhaust shop to get mufflers on it so I can get it inspected.