Did the 65 gt350 HiPo dizzy have a 10L/13L or 13L/18L reluctor ? That's the 8 sided points cam.
10/13 only on centrifugal advance distributors.
Thanks Randy
That's what I thought, but wanted an expert to chime in...
I hope "he " does LOL! I'm still learning. ( well some stuff anyway)
Keep in mind, what your '65 289 HiPo Distributor came with it may no longer have the correct part in it. Here we are 55 years later with these cars and parts going through many hands and mechanics. Sometimes a really pitted points cam may have been replaced by a 13/18 simply because the 10/13 points cam is harder to find. I was rebuilding a BOSS 302 distributor last year for a client and it had a C5AZ-12210-B points cam in it. That would have been the correct 10/13 points cam for a 289 HiPo. However the BOSS 302 has vacuum retard and advance so the points plate has a bearing in it, this raises the actual points plate enough that it requires the points cam to be significantly higher. You can tell this points cam by the groove in the too of the points cam. Just because what you have is what you have doesn't mean it is the right thing. One of the reasons I photograph everything that arrives, documenting all the parts on arrival and disassembly.
John