Thread: My 502 ain't got it....what am I doin wrong?...Please Help!

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I just fired up a 3-year build up...a 69 Impala, 502-4spd, 4.11 geared whale. I had the usual problems with a new ride, and I got most of em solved...but I still can't get the 502 to be all they say. Its the 8.75:1 street version rated at 450HP and 550 lbs.

I'm convinced the source of the trouble is the ignition. I'm running a full MSD set up, 8361 street billet dist., blaster coil, 6AL...you know the usual. Right now it is timed at 36 degrees total running at 2500 or so...which winds back to 17 degrees at idle. Thats with NO vacuum advance hose connected, and tiny advance springs. It fouls the plugs within an hour of street time, and starts dropping cylinders. I've tried several carbs, with some improvement...but the problem still exists.

So, here's where I need help. Does anyone know what curve I should be running on this? I do want to use the Vacuum advance...but I'm not sure where to connect it. Seems everyone has a different opinion on that one...whats yours? Finally...what total and initial settings are all you other BBC guys running? (this is my first rat). Keep in mind...this is a fairly mild motor. GM says to set it at 4 BTDC, which runs like crap. Perhaps I need more "travel" in my advace mechanism? Any help would be appreciated.

Thanks- CJ in Indiana