Chevy distributor conversion questions.
 

I'm attempting to convert an old Accel distributor and have a couple questions.

I can't find the pin that retains the gear for sale anywhere, is it just a roll pin?

How you you handle the "reverse rotation" issue?

Thanks!:)

Re: Chevy distributor conversion questions.
 

I'm sure a roll pin will drive the Chev distributor in a flathead application since there's no oil pump load as a Chev has. As for the rotation...same as chev. No problem.



Terry

Re: Chevy distributor conversion questions.
 

Thanks Terry.

Re: Chevy distributor conversion questions.
 

Yes Roll pin works just fine.

Re: Chevy distributor conversion questions.
 

I've always used a roll-pin even with the oil pump.

Re: Chevy distributor conversion questions.
 

Don't know what I was thinking about the rotation thing, there's even an arrow on the cam showing the way it spins.:rolleyes:

I'll drill it for a .125" roll pin and get on with it. I'm thinking of taking one of the sets of points out (they are new) so I'd have a spare set. I can't imagine a few extra degrees of dwell doing any good on this low RPM engine?:confused:

Re: Chevy distributor conversion questions.
 

I agree. With a modern coil you're going to have plenty of spark energy to light up the fire in the flathead. The dual points were good for the old lower-output coils.



Terry

Re: Chevy distributor conversion questions.
 

Well, she's done!:D
Need to figure out a way to keep it from turning next.

Re: Chevy distributor conversion questions.
 

A good starting place is 16 degs all in at 2k and 8 degs vacc. and go from there.

Re: Chevy distributor conversion questions.
 

Unfortunately the distributor does not appear to be the preferred type that has vacuum advance capability.

Re: Chevy distributor conversion questions.
 

Correct, no vacuum advance on this one. It'a an Accel brand dual point unit from the 70's. I do have a genuine Chevy unit to experiment with as well. Thanks for the setup info. The Accel unit has interesting "stops" built in to the advance mechanism to set maximum advance.

Re: Chevy distributor conversion questions.
 

I converted a similar Accel SBC dual point but, it has the vacuum advance. Works great.

I shaped a thin piece of aluminum like the stock distributor housing (that gets clamped down) and used the Accel housing screws to hold it on the bottom of the Accel distributor. I am able to use the stock hold down.

Can't find the pics. I think I posted it on this forum though.

https://www.fordbarn.com/forum/showthread.php?t=243704

Post #8 shows my pics.

Re: Chevy distributor conversion questions.
 

Thanks, I'll investigate that solution. Guess I should've remembered that since it was my thread too.:rolleyes:

Re: Chevy distributor conversion questions.
 

Tuning any engine takes bith Nac and vac advance to provide proper power and economy. So why not use one??

Re: Chevy distributor conversion questions.
 

Having both mechanical and a vacuum advance is a good idea, that is why the factory did it. But I have run straight mechanical advance on many cars and it always suited my needs. Sometimes it makes life a lot simpler.

Re: Chevy distributor conversion questions.
 

I'll get around to it Ron, just playing with this one first.:)

Re: Chevy distributor conversion questions.
 

I made a simple wire bracket to lock the distributor down. I think if it were a half circle shape I'd like it better. She fired right up!:) After a little dialing in, it has better throttle response than with the stock distributor. I have a set of SBC advance tuning springs coming to try out.

https://www.youtube.com/watch?v=ITelbg7ZYpU

Re: Chevy distributor conversion questions.
 

The little bushings in the advance plate control the amount of advance, the springs the rate. Unfortunately the kit doesn't have a light enough spring, and this is the trickie part, and is best done on a dist machine. or street I use just 16/18 degs total. however this has to work with 6/8 degs of vacuum. Now just to confuse the issue the AF of the carb also plays a roll in the tuning process. Richard spent over a year and many$$$ developing the instruments to monitor the engine through it's operating range. He also developed the adjustable mechanical advance system. Now all this information is free to the rest of the builders of these engines. I'm the keeper of this equipment and hopefully will us it in the future on an inexpensive EFI system. The main reason I/WE share this information is to improve the longevity of your build as poor tuning is one reason these engines didn't last very long, few everlasted 100k. I'd like to keep them around for awhile longer.

Re: Chevy distributor conversion questions.
 

Art, let me know if you find light enough springs. I got mine dialed in to work but, with only one spring. Two of the lightest springs I had were too heavy.

Pretty slick idea for the hold down.

Scott

Re: Chevy distributor conversion questions.
 

I'm going to re-make the hold-down in a circular shape using the old distributor as a guide. It's .125" music wire (piano wire) silver soldered to electrical eyelets.

We'll see how the springs workout, sounds like we want all in at approx 2000 RPM. Shouldn't be too tough to make springs if needed.