I was rummaging through my garage and found a NOS Accel 43100v vacuum advance dual point distributor. I’m putting together a budget mild SBC and it would be great to use to save some bucks as long as it will work well. I don’t see any weights or springs for any mechanical advance, so wanted to know if the only means of advance is vacuum only? It seems to me that the combination of vacuum and mechanical might be better. Any insight or advice would be great. Thanks
Is it possible you transposed the first two numbers? In any event if you are looking for the advance weights and springs as on the typical GM points distributor I think the diameter of that Accel may be too small, the advance mechanism might be found under the points plate. Edit- Do a search for Accel 34000 distributor installation manual, it do***ents how to change the advance.
https://static.summitracing.com/global/images/instructions/acc-34000v.pdf This may shed some light...
Thanks guys. Attached are a few pics I pulled from the web but it’s the same distributor. As you can see there are no weights and springs, just the rotor attached to the shaft. Could the advance mechanism be below the breaker plate?
I have one on my 351W (34201S) and here's a picture of it dis***embled (except for the white curved pieces)... If you remove the two screws at the base of the housing you can remove the top half of the distributor and gain access to the advance springs and the screw on the base of the points cam that is used to adjust it. If I remember right there are four holes for the limiter screw that are marked 10, 12, 14 & 16, which corresponds to 20, 24, 28 & 32 degrees of advance. I set mine at 10 (20) with a base timing of 16 for a total of 36 (not including vacuum advance). Honestly, the distributor is a piece of ****. It's good idea but a poor design. The points plate flops back and forth as the points open and close, making it run like ****. It gets worse as the distributor wears, as I learned. I almost pitched the turd but I decided to see if I could make this thing function. My solution was the two white curved Delrin pieces next to the snap ring. They are mounted under the points plate, keeping it from rocking back and forth and providing a smooth surface for the points plate to ride on. It's been over five years and it's still working perfectly. Here's a pic of the inserts installed to the housing. I drilled and tapped the housing for screws to secure the inserts. It works great now and I use it to trigger a MSD 6T with timing control and rev limiter. Check your distributor points for play by grabbing the points and pulling up on them. Whatever movement you see is what will happen as the engine is running. Hope this helps!
Wow!!! This is amazing isn’t! Thank you! They sure didn’t make it easy to adjust in car, especially with a Chevy mounted in the rear. I see they make a pertronix unit, but at that price I can buy a new distributor. I’m trying to avoid a Chinese knockoff which seems to be what’s available at my tight budget. really appreciate the info!