[SCOBRAC]

Hmmm...

Well regardless what your static timing whether it be 10 or 20, at 3500 it will be whatever it is plus whatever the distributor allows it to be. 10 plus 24 is still 34, as is 18 plus 16. In either case 36 degrees will generally get you detonation in an iron side oiler. Remember I'm at 11:1. This compounds the problem, as does the 306 (at .000) cam. Ad 91 octane "premium" fuel, 200 pound cylinder pressures and limited spark plug choices.

As far as warping the side of your car I suppose anything is possible. I will point out that the factory timing was 6 btc. I'm not sure how I would get the thing to idle with 18 degrees initial timing. That leaves 16 degees to play with. The largest bushing MDS offers, the black one allows the distributor 18 degrees of travel. 18 plus 18 is 36. If somebody (not me) tries this please let us know how it worked out. It might be fine in a 9:1 engine with 270 degrees of cam.

Too many variables exist to find a formula right for everyone. Combustion chamber shape, plug location, cylinder pressure, load, vacuum, fuel octane all play into this equation. That's why you never want to compare aluminum engines with iron engines.

I took it back to 8 btc and it was like herding turtles. It just didn't respond. I have gone as high as 12 initial with a bit more diesling on shut down and too much idle. I guess I'm back to using fuel additives.

It seems to be happiest at 10 with the silver bushing, that's 35 degrees total timiming. I opted again for a light blue and light silver spring which gets it all in by 3200 or so.