[Fishin2Deep4U]

Okay guys, I know this is a loaded question and subject to interpretation. But how do we obtain the "optimum" timing curve for all RPM and load conditions?

I have converted to MegaSquirt, current using an HEI allowing the springs, weights and vacuum advance to do their thing. But, I am going to swap to LS truck coils, so I will be able to dial in the spark curve any way I want it.

I would think a load dyno sweeping through from closed to WOT at a braked RPM would be the most efficient. So you can see power changes based on individual cells within an RPM range at at a sweep in vacuum. However, this isn't practical. So, Other than starting with a working dizzy setup, in my case 14 initial, 20 mechanical by 3500 with another 8 (16 crank degrees) from vacuum, how do we make it better?

My load dyno at work won't work for chassis use. So that's out.

Any bright ideas? Not a track car, definitely a driver. Not chasing every last drop of power, but want the low hanging fruit. The car could use a little more vacuum advance. And the fuel curve will be changing a little as I am going sequential. So, I'll be pulling some fuel off the bottom.

455
9.7:1
6X-8 heads. crossovers filled, 1.77 exhaust, just port matched and cleaned up.
284/292, 236/244@ .050", .510"/.505" @ 1.5 112CL

I can add a knock sensor, but I have not spent the time to figure out the proper frequencies and may just be a bigger bag of cats.

Other than listen for knock, read my plugs, ect. Any tips?

Thanks!

Dave