just pulled the msd distributors to put in new mallory ready to run and the mallorys do not have a groove on the shaft for an o ring the msd did and it had o ring installed should i run the mallorys ?

Most of my msd's have the groove but no orings. Stock ones don't have an o ring either

you don,t use the o rings with a standard type oil system.

Is there any advantage having them? Do the o rings keep the oil the cam gear ?

if you look at the instalation instructions from msd it will show what the o rings are for.only to be used on modified block.

yes msd shows to chamfer the hole so as not to damage to orings my concern is that the block has been chanfered do i have to run a distributor with O rings ?

Anymore answers?

Prob wouldnt be a bad idea to to a little test fit and chuck up the air drill. See if you can get a peek down in tbe valley and make sure your not bleeding off too much lifter galley oil from the dist housing there . Plus if you have a slip collar now you will know its where its supposed to be

If the block is machines for o-rings I would use them. The distributor is a critical part of the oiling system for the right bank top end oiling. I've seen many motors that didn't have the distributor shaft lined up properly to the oil galley resulting in oblonged lifter bores and bad lifters.

It would be very simple to machine the new distributor shaft to accept the o-rings if needed.

I took them apart last nite already at the machine shop