Reply to "Parts needed to convert duraspark?"

Even the high performance Fords came from the factory with the big heavy weights.

Generally speaking that meant that they would be all in somewhere around 5,000 engine rpm, 2,500 distributor rpm.

How fast you get to the total and how much it will take depends on how your engine reacts to the gas that you use.

When you use the quench chambers and the pop-up pistons you wind up with 11.6 to 12:1 static compression ratio.

That is too high for 93 out of the pump. It will almost detonate without a spark just turning the engine over.

If you use flat top pistons and quench you are somewhere between 10.6 and 11.1:1 depending on what cylinder head and gasket you use. The 10.6 is about all you can run with 93 octane.

CR with dished pistons and quench heads. Should be 10 to 10.1 to one. I find that a slugish combination with the 4v ports. Maybe the 2v heads are better with it?

Clevelands like a lot of total advance. The "book" is actually 36 to 38 total degrees. The engine is crisp and responsive there.

The racers, particularly drag racers would go all in by 2000 to 2,500 engine rpm.

Two things with that. First the springs are so light they don't last long and stretch out easily. Second is that the gas will detonate because the advance rate is creating increase in cylinder pressure beyond what the gas can handle.

Some have compensated, or tried to by using a dual pattern cam. One that leaves the exhaust open longer so that the piston blows some of the pressure out of the exhaust and lowers cylinder pressure.

I personally have tried all of these combinations here. I found that a regular performance cam with 72 to 73 degrees of overlap, an aluminum quench head with a flat top piston, a total advance of 36 degrees and a slow advance to all in around 5000 engine rpm for me gives the best combination.

It is to the point now that I really should convert to an ignition with a CPU that has a knock sensor on the engine, will compensate automatically by backing off the timing until it doesn't hear knock, records past unsuccessful advance curves and can be recurved electronically with access through my laptop.

That is the only way that I can get more out of the engine other then running 106 octane leaded racing gas, which for me is just not going to happen.

You can use the MSD system as George has suggested. I find their products way below average as far as dependability goes and stereo typical of third world crap, but that's just me. Others love them.

I should also point out that it seems that every time I hear a story about the distributor gear drive pin failing, it always seems to be an after market distributor or one that has been "rebuilt" by a local shop.

I went that route years ago and had nothing but failures on the Accell, and the Mallory. I have not run the MSD distributor and I probably won't.

I do have a stack of failed MSD boxes that I keep in the shop to remind me how stupid I am. When I start to weaken and think about a billet MSD and just look at the broken brains stacked there, I come to my senses.

You are right though. You are going to have to determine what timing works best for your application. Not too many people talk about the Cleveland any more and it isn't a Chevy and you should keep Chevy experts away from it.

Any performance development that has been done on the engine series in the last 10 years is largely coming out of Australia. You could use some of their information for sure but remember they are largely using the 2v which has enough differences then the 4v to put you on your own.