You have a dist. Machine have you every checked out the yl mallory dual point dist. One with the 4 lobe each set of points only fired 4 cylinders.

 

I have used those dual point Mallory units in cars, but I've never run one on my SUN machine. I don't see any issue with running one and setting it up on a distributor machine - it will run the same as any other distributor except that you need to isolate each set of points when setting the dwell. I don't advise using those distributors in street cars since they do not have vacuum advance.

Lars

 

The YL dual point was a freakin staple of early racing as it just plain worked well. Two things though.......as Lars states....the dwell has to be set separate.....but getting them in sync is very important so the dwell should be spot on on both sets. The other thing is never leave the key on as you will now smoke a pair of points rather than just one......
Oh and no vac advance as stated.

Jebby

 

That's correct: If the one set of points has 2 degrees more or less dwell that the other, then 4 of your cylinders will fire 2 degrees advanced or retarded from the other 4. But all that said, there is no good reason to run a distributor like this in a street-driven car unless you have a high-rpm engine with very high compression and a big-*** cam with not enough engine vacuum to operate a vacuum advance.

Lars

 

Well my defenition of a street engine or street car is not anything like most people want. If you can still license it and run it on pump gas thats all i want. Also to me the sbc is the poor mans high rpm ferrari if your not willing to rev it build a large cube bbc and be done with it. Yes everything i have ever built or wanted had an idle rpm of 1000 rpm on up. So vacuum advance or a bit better economy not in my vocabulary. Back in the seventies i bought a new yl mallory and ran it in a 331 and 396 bbc. My 69 z/28 that i had from new never had a points bounce problem for a long time. But back then in my youth just bought whatever auto parts store points for it and ran into some points bounce. So i cut off another points spring and put it in behind a new set of points that fixed the problem and it did not seem to ware the points block out any real amount sooner. I did not know that accel in that time period of early 70s were making stiffer spring points. Wish i had kept the mallory looks like you can still get replacement parts for it. Funny thing i just bought a series 1 1955 3600 3/4 ton pickup with the 235 six. You can buy new dual points distribor for it or a breakerless. Why in the hell would anyone want a dual point for a damn 235 six cylinder. Summit, jegs, competition products do not show mallory dual point dist. For gen 1 sbc so without calling mallory assuming they stopped making them.

 

Sounds like you have it figured out.
Lars