The Stovebolt Site Forums The Shop Area Engine Shop HEI Distributor

I've put the hei distributor from a 80 Chevy truck in my
55 235. I got it in fine and the timing is right on the money.
Only thing for some reason the motor just isn't running as
good as it did with the old distributor.
Any hints on what I might need to try next to make this work better?
If I can't get it running any better than this I'm going back to the original!

Did you bypass the ballast resistor on the firewall? These dizzys need a full 12 volts.

also check that the mechanical advance moves freely.This can be a problem with used disributers.They can get stuck fully advanced

I don't have a ballast resistor but I will check the advance.

The HEI distributor was designed for use in motors conforming to smog controls. In most all cases the HEI distributor has less mechanical or vacuum advance than pre63 distributors. I would have the HEI recurved for the original specs on your motor. If you want to DIY I have some text files that will give instructions. That's not to say that there may not be a problem with distributor. IIRC the instructions include disassembly and maintenance. send me a pm if interested, they are to long to post.

Larry

When I did my HEI conversion I initialy set the timing to factory specs, but after driving it, I had the same impression that you had, it ran better with the stock dist. I read about setting the timing slightly advanced with this setup, so I did and now it seems to run alot better.

When I'm setting up a HEI for round track racing, I restrict the centrifugal advance to about 8 to 10 degrees less than usual, and add a corresponding amount to the initial timing. The small block V-8 works best with a combined initial and centrifugal advance of 36 or 37 degrees. I put in about 24 degrees of centrifugal, and set the initial timing to about 12 or 13 degrees BTDC. This gives batter acceleration than the standard initial timing of 4 to 6 degrees without over-advancing at higher speed. The centrifugal timing should max out at about 2,500 RPM, which is controlled by spring strength. Vacuum advance on a street engine adds about 10 degrees at light-throttle cruise for fuel economy.

Find a set of distributor specifications for the stovebolt engine, and adjust the HEI as close as possible to those specs. The above numbers work for 283, 305, 327, 350, etc.
Jerry

I thought FCMullins had a 235 six cylinder in his rig not a V-8. He didn't mention if he used it for round track racing or not.

Stuart

Don't forget to change or regap the plugs to HEI spec, too.

Best wishes,

Les

LOL!