C3 (71 Base Motor) Distributor Endplay

[Pat Bush]

Hello all -

Quick question - I am rebuilding a 71 dmall block distributor. Does anyone have a spec on the main-shaft end-play? I have around .030 and I am thinking that is too much. I have a shim kit ready to install -- but thought I would ask the board's knowledge base first.

Thanks in advance -

Pat

[John H.]

Re: C3 (71 Base Motor) Distributor Endplay

Pat -

The end-play spec for Chevy/Delco distributors has been .002"-.007" since 1955, but you don't see many that way; it does make a difference in timing accuracy when they're set up to spec.

[Pat Bush]

Re: C3 (71 Base Motor) Distributor Endplay

John -

Thanks for your response! I looked for this info but was unable to find it anywhere. I ended up setting it up to .010 and hoped that would be sufficient -- I got that value from a place that rebuilds corvette distributors. I thought it too seemed a little high, but the fellow insisted that this was correct. The car runs very strong now. It was like .030-.050 when I took it out and knew that was WAY too much! So, I think this summer, I will leave it that way unless you see some really pressing reason I should pull it now. The timing has not moved in the last week of driving

When I detail the top-end this winter, I will pull it and re-shim to .004 (I always split the difference on clearance tolerances).

Thanks again for your reply!

Pat

[Chas Henderson #28127]

Re: C3 (71 Base Motor) Distributor Endplay

pat,
I don't want to rain on your parade, but if you have too much slop with your end play, you run the risk of taking out either your main shaft teeth or your cross gear teeth. And a good chance of doing both. So if your tach isn't working you will be ok, the damage is probably already done. If it is working I would either unhook it or remove the distributor and tighten up the end play. I have gone down that road with my 71.

good luck

Chasman