Ok so i got an accel distributor last week (i know what your gonna say). Ran great, actually better than it ever did. I put an etropy radiator in (electric fans). And thats all I did. All of a sudden one night, i get gas and it wont start. Finally i get it started and its back firing down the headers and running like its on 6 cylinders. I go home the plugs are fouled. Ok so I change those, runs great. Drive it for 20 minutes, it does it again. Ive been doing this same change the plugs drive it for 20 process for 3 days. I changed the plug wires, same thing. Tried a different carb, same thing. Put the old carb back on same thing. Thought the valves might be too tight or something. same thing.


So Im guessing, if once the distributor gets hot will it start crapping out like that? I was under the impression a distributor will work or not work.

Anyone know what could be doing this? Im assuming its an ignition problem thats why the plugs are fouling and its missing at half throttle. Eventually it will just crap out if you keep driving it. Whats the deal!?!?

I have had that issue with 3 Accel distributors in the past. Find a good HEI at Summit and throw it in. As I am writing this A Friend is towing his car ( 1970 Impala with 350) over here to have me look at his Accel distributor and get it running again. It has been backfiring into the "Edelbrock Carb / Intake Combo"

I am going to pull that Distributor out and put either a HEI or a Points Dist. In it.

I am not a Guru of Accel but They have not been kind to classic cars as of late. The Product is lacking, as well as stranding the Hobbyist. I have not had luck with them as well as others I know.

I had an hei in it, ran fine with that, problem is its a big block and its tight on the firewall so i went with the smaller cap style to get the clearance.

Any suggestions on a small style cap set up? msd? (part numbers if you could thanks)

Ok so i got an accel distributor last week
Did you recurve it to the old and is the VA the same specs?
Not doing so is like....swap a diff and find afterwards you have gone from a posi to std diff and 4:11 gears to 2:55 then expecting the car to go the same.

Actually i did not, however!! It ran awesome (the accel dizzy ) for about a week. Then it started all this crappin the bed stuff. So if it was a curve issue it would be there from the start. I think we can rule that out, agreed? The old dizzy was an hei, i wanted to swap it to a small cap external coil for better firewall clearance (big block).

After i went from the hei to the accel dist. It ran fine, actually a bit better. Then a week later, it gets a little hot and falls on its face, backfire cant rev it up at all etc etc.

Then a week later, it gets a little hot and falls on its face, backfire cant rev it up at all etc etc.

Have you tried a different coil?

Actually i did not, however!! It ran awesome (the accel dizzy ) for about a week. Then it started all this crappin the bed stuff. So if it was a curve issue it would be there from the start. I think we can rule that out, agreed?
Sort of..
If it is now swinging out too fast or total Cent+ idle is further out, or the VA is diff spec ... put it like this over advance dosnt produce more power, but what does do is produce a different sound from the engine... a more 'grunty sound' that is distinct enough to definately give the impression of more power...which is the core reasoning with ppl seeting timing by "ear" and seat of the pants...then further down the track blowing pistons , rods, bearings, burning valves , blame on something but usually someone else and dont give the timing change a 2nd thought.

I doubt you have done the miles nor changed the advance enough to cause damage at this time..
A note on clearance with GM HEI...well this appliies to SB...Im assuming similar with BB.
There are servral types of engine stands and several types of engine mounts and serveral type (heights) trans mounts.
Here in NZ the normal off the self trans and engine mounts are usully 1 type.. not many people take the orginal ex factory mount (and lets face it how many still have the stuffed thing stored after 40 od yrs?) in put them side by side and measure.
What i found was the trans mount was (from memory about 10mm shorter) and the only one they stocked....simlar with the engine mounts but they did stock mine.
So after tying to source the corect mount unsuccessfully I made up a spacer out of the approate height plate steel , longer mounting bolts and put in.

I put my late model recurved GM HEI in yrs ago...didnt know about the firewall issue, with correct mounts...I had to shave the plastic plate that the lead boot clip into off to clear and get full turn.. clears the back of the plastic plat a couple mmm as does the rear boot.
The other issue that could be...havnt tryied this, is the Dizzy not being in the factory position that with the VA ponting to just behind the passengers headlight and #1 at the front.

Well i took it out for a test drive with a new hei back in it, it ran awesome. I know what your saying about curving it. I fine tune that tommorow if need be.


I have an msd 8361 on the way with a blaster coil. Im hoping i dont have problems with it.

So how about timing, curve etc? Whats a good starting point? (idle, then at say 2000+ rpms?) Should I be using a vacuum advance at all? Or should 34-36 total advance be it all the time? I want to get it right and keep it that way.

Thanks for your help in advance. (no pun intended)

You should always use vacuum advance on a street car. There is a good thread on that but I can't find it right now. Use the search function and you will probably find it pretty quick.

If you old dizzy was dialed in then put it back in, get some graph paper , disconnect the VA... and read off deg points at idle 1200 2000 2500 3000 3500 rpms till it stops moving
you will most likely see that u get up to say 3000 or so and stops but there is a tiny liitle more over a lot of rpms...dont worry about that, its caused thru worn shaft bearing and worn counter weight bushes
Now u have you cent curve graphed to put in the new dizzy
The VA.....put a vac pump...the ones used for vac bleading brake dupicate for this use.
take the dizzy cap off, put you finger on the actuating arm, start pulling a vac undtill you fell the arm moving...note the start vac...
keep pulling vac till it stops moving...note the finish vac
Now u have to find the amount of degrees in it
Fire up the car, no VA attached....hold rpms about 1200...note the crank advance say 12 degs...using the vac pump start advancing the timing with the VA unit...and at the same time keep the rpms at the 1200 rpms (this keeps the cent advance at the same piont) keep pulling vac on the VA till advance moves no longer and the engine still at 1200 rpms....note the timing mark... say 20 degs
20 minus 12 is 8 thats how many degress in the VA.

To do this and reset calibrate the new dizzy u NEED to have the harmonic balancer marked of in 5 deg increments upto 45 or 50 degs...

If the old dizzy was way out or never calibrated....u need to sort the Cent before even thinking about the Va, and need an incar vac gauge
Sort the intial requirement...No VA attached, increase the advance at your idle rpm till it goes from real rough to stable but smooth as , if you have bit od a cam in in it.
This will be between 8 deg and about 14/16.
This degree will eventually be the intial (no cent) plus what is in the VA for manifold vac.
The total cent will depend on you diff ratio, cam , rpm range of the engine, type of heads etc...it will not be over 36 deg and most prob around 30 to 34 deg at around 3000
A road test up a big hill, with engine over 3000+ rpms so the cent is all in (a lower gear helps) retard the dizzy back till you notice a drop in power... between 2 and 4 deg above this will be the ball park for total cent advance.
The VA adds advance for very light load and cruise and all in at the idle.
you need the intial about 8 to 12 degree plus the what is in the VA all in when the engine fires to take up to best idle advance established above... and also have the VA only just in at the vac the engine engine pulls at 60 mph going up a gentle slope at a constant speed.... a slight acceration or slightly more slop the VA will be be dropping out.

The amount of dregee in the VA should not take the total intial plus the cent plus the VA all in above about 45 degs at 50 to 70 mph range.

This sounds confusing..take each part/step one by one, then think tru what is happening and it will all fall into place.
You can do this a bit more accruate with dyno time but that is real expensive....and the differece between the 2 negitable.

Ball park summary
intial about 8 to 12 degs...with VA 12 to 18 degs (somewhere between 5 to 10 degs in the VA)
Cent will start moving about 150 to 200 rpms above idle in gear (auto) and be all in around 300 to 3400 rpms with between 30 and 36 degs....
With the intail 8 to 12degs total cent 30 to 36 total in the cent (not incuding intial ) 22 to 26 degs
the VA will start to work in the 6 to 8 " and be all in around the 12 to 15"