Accel Distributor w/no Advance

[Ed T.]

My 62 came (to me) with an Accel distributor (Model 30100T). This distributor has no vacuum or mechanical advance! Is this possible? I'm looking for any info on this distributor. Accel does not reply to my questions. BTW, I'm trying to solve an idle overheating problem. Related? Thanks...Ed

[Joe L.]

Re: Accel Distributor w/no Advance

Ed------

There are many hi-performance distributors that are designed without vacuum advance. That's very common. Some Corvette original distributors also lacked vacuum advance. However, a distributor without mechanical advance? I don't think so. I can't imagine what use that such a distributor would be; the engine must have some sort of spark advance mechanism and, for pre-computer-controlled applications, as far as I know that mechanism was always in the distributor.

The Accel part number that you provided looks like an old part number to me, so I can't imagine that this was a distributor designed for a computer-controlled application.

All that I can figure is that someone modified this distributor to eliminate mechanical advance and I can't figure out why.

[John H.]

Re: Accel Distributor w/no Advance

Ed -

Yes, it's related. In order to get adequate idle cooling, vacuum advance is essential in order to add 15-16 degrees to your base timing setting (also essential for part-throttle driveability, throttle response, and improved fuel economy). The Harry High-School non-vacuum advance Accel stuff appeals to kids afflicted by the Summit/Jeg's "race car" marketing syndrome, but it's junk for a street-driven car. Bubba is everywhere

Rebuilt (or rebuildable) Delco point distributors with vacuum advance are plentiful and inexpensive.

[Joe L.]

Re: Accel Distributor w/no Advance

John------

Yes, I totally agree. I would NEVER use a non-vacuum advance distributor on a street driven car. I'd probably want to switch to vacuum advance even if I had a Corvette that was originally built without it.

As a matter of fact, I have 2 NOS GM #1111263 [none for sale] TI, ball bearing distributors. Neither will find a home on my "ZL-1" since they don't have vacuum advance. PRODUCTION ZL-1's did not use this distributor, but they did use a non-vacuum advance distributor. I wouldn't use that distributor, either.

[Ed T.]

Re: Accel Distributor w/no Advance

If it had mechanical advance, someone removed it. I just started her up and then manually gave her about 20+ degrees advance and let her run. The overheat problem has disappeared. I had removed the thermostat (180) to try and get her cool. Now she runs just a bit off the botton peg. Time for a new distributor. Thanks...Ed

[Clem Z.]

Re: Accel Distributor w/no Advance

the ball bearing dist was for the reverse rotation gear drive cam and it was needed because the thrust on the dist was downward because of the cam rotation and if you tried to use a std dist with the correct gear for the cam it would just eat the top bushing down.

[bob downs]

Re: Accel Distributor w/no Advance

ed, pull that piece of junk out and put the correct distributor back in. along with that put the thermostat back in also. have the distributor set up with 12% and then set your timing at 10%. this will give you a total of 34% which should work great.

[Clem Z.]

Re: Accel Distributor w/no Advance

it is common practice to "lock out" the advance on supercharged engines to make sure that it does not over advance the total timing which would be "death" to the engine. this is done by removing the advance weights and welding the whole thing solid and setting the total to 28/32 degrees. some times you have to use a seperate starter button so you can spin the engine before turning on the ignition to prevent "kickback".

[Ed T.]

Re: Accel Distributor w/no Advance

The distributor was not the only piece of junk on this car. But that's what makes working on her fun. Thanks for your comments...Ed

[Ed T.]

Re: Accel Distributor w/no Advance

Hi Clem,

That would not supprise me at all on this car. I couldn't figure out how one would start it with that much advance, but your comment explains it...Ed

[Joe L.]

Re: Accel Distributor w/no Advance

clem-----

Yes, if I were to use one of the '263' distributors with a chain drive cam, I'd replace the drive gear with a conventional gear. However, due to the lack of vacuum advance, I doubt that I'll ever use these distributors. The '263' distributors cannot be modified for the addition of vacuum advance without impractical work. The original L-88/ZL-1 PRODUCTION non vacuum advance distributors can be easily modified for the addition of vacuum advance, though.

[Joe L.]

Re: Accel Distributor w/no Advance

Ed-----

Yup, that's what time it is. And, like John mentioned, these distributors are not difficult to come by. A 61 without FI didn't even originally use a tach drive type distributor, so a run-of-the-mill Chevrolet distributor core is all that you need.

[Clem Z.]

Re: Accel Distributor w/no Advance

joe,back in the good old days i always had full advance at 2500 rpm and i replace my vacuum advance with a threaded rod so i could adjust my timing by turning the wing nuts. i would set the timing with a light but i could change it without the light just with the threaded rod moving the plate. i knew how many turns of the wing nut moved the timing x number of degrees. this came in handy if you got some bad gas or needed a little more advance if you picked up a street race at the local drive in. you have to remember that gas was .25 gallon and with 4.56 or better rear gears gas milage was not even on the radar screen.

[Ray C.]

Re: Accel Distributor w/no Advance

Joe,

I recently posted a question on a tach drive distributor. The previous owner cut the vacuum advance bracket and tube-rod even with the casting and welded it smooth. I had the weld and bracket machined out, but the weld weakened the thin 3/32" casting below the rod or tube slot. This increased the slot by 1/8" to 3/32" in depth. Should I replace this missing casting with a low temp weld and grind or file to the correct depth? This is the original #1111076 distributor. Does GM still provide rebuild kits for these distributors or will I have to use after market replacement?

Thanks for any help!
Ray Carney

[Joe L.]

Re: Accel Distributor w/no Advance

Ray-----

If I were you, I wouldn't fool around with trying to repair this distributor housing. I'd obtain another one and transfer any usable parts from your existing distributor, INCLUDING the ID band.

Corvette distributor housings were not unique to particular distributor part numbers. There were really only a small number of housings ever used for all tach drive distributors. Obtain another one configured like the one you have with particular respect to the oiling groove found on the lower end of the distributor----some have a full circumference groove and some have a partial circumference groove. Otherwise, differences in the housings are fine nuances.

There is no rebuilding kit available from GM for these distributors. In fact, no kit was ever available from GM---only individual parts. Virtually all of those are now discontinued, except cap, rotor, points, and some vacuum controls (although even these parts are not configured like the originals).