Got Shell 93 Octane and now barely idles 1973 Dart 340

nm9stheham said

You will need tools to keep this type of car in good shape. Your first needs to be a timing light if you don't have one.

Timing by ear can be a disaster. Read pages 3 and 4 of this thread: Problem with Mighty Demon 750

Click to expand...

I do have a timing light and look at initially with it and it was at the top of the marks about 10 degrees someone told me on the thread by the marks. Earlier in the thread I stated that the balancer timing mark initially was at the very top mark just past (below) the water pump housing. It was stated that this was not optiumum. So I advanced it just a little until the RPMs raised and then backed it up. Without anymore timing marks on the engine, how are you to know what to set it at? I have since put it back to 10 degrees until I have the brake booster done.

Per this thread: 340 timing need some advice on rufff timing

"It's not uncommon for 340's to want 20* of initial timing. You might want to toss the factory timing specs in the garbage, they aren't set up for best performance. You've also changed things some, that throws a wrench in things.

Basic idea with car at idle speed you want, turn the distributor giving more advance, if the engine picks up RPM, it wants the advance. reset idle to where you want and repeat. You'll reach a point where it won't speed up much at all, you found where the engine likes initial timing level. As long as it will start when warm, not kicking back on starter or straining you then need to work on the mechanical curve in the distributor."