Distributor Cap Differences

[Stephen L.]

I have 2 GM distributor caps that have the identifying "Patent Pending" no "R" nomenclature. The difference is the height of the sparkplug wire towers. One has towers that are 7/8" high while the other has 5/8" towers. Both have aluminum inserts.

Is either more correct for a 67BB???

The shorter towers give more clearance under the shielding cover.

[John H.]

Re: Distributor Cap Differences

I have 2 GM distributor caps that have the identifying "Patent Pending" no "R" nomenclature. The difference is the height of the sparkplug wire towers. One has towers that are 7/8" high while the other has 5/8" towers. Both have aluminum inserts.

Is either more correct for a 67BB???

The shorter towers give more clearance under the shielding cover.

Steve -

Didn't F.I. cars use the D-310 cap with the shorter towers than the D-308?

[Jack H.]

Re: Distributor Cap Differences

Yes, and your picture looks JUST like the one from my parts file folder, John!

[Wayne M.]

Re: Distributor Cap Differences

here's another view of the short tower D-310, used on '64-5 FI cars for sure (with 90 degree plug wire boots at the cap end). I think the C2 BB distr. shield surround and top was designed to accept the taller cap [with the 90 degree boots, of course].

[Stephen L.]

Re: Distributor Cap Differences

Thanks for the feedback. I picked up the short tower one at the scrap yard. Don't remember what it was on but it sure wasn't a fuelie....

[Mike M.]

Re: Distributor Cap Differences

60 Olds 394 ci engines used the short tower distributor cap common to the midyear FI distributors. mike

[John D.]

Re: Distributor Cap Differences

NAPA has nice black/copper low tower distr caps RR168 for less than 20 bucks. No good for Flight judging but good for everything else. Stock up before they are history like everything else. JD