I don't know the cause of the failure,but I would try another distibutor if possible....I have not heard a lot of good things from the Mallory distributors and they seem to be rare around here,90% use MSD.......Have over 10,000 miles on mine in my Mustang with a 351-W with no problems so far.....
Mr. Bruce,I have seen the insides of a standard pump and a HV pump,quite a bit of difference in the gears.... Seems to me,on that point alone,a HV pump would require more "force" to turn it than a standard pump thereby putting more "strain" on the cam/distributor gear,not talking about a HP pump,but HV only.....I understand the extra volume of
oil not needed or used goes out the bypass,but the pump still has to pump it in the first place?????? I do not know how much more it would/should take to turn a HV pump,maybe not much,but so far I'd guess 90% of the gear failures I've seen were using a HV pump and more often than not,a heavy weight
oil....Just thinking out loud!!!!!!!!!!!If you have info saying the HV pump requires the same force to trun as the standard pump,please pass it along to me,I'm very interested in this right now......
Getting ready to build an aluminum headed,high compression (13 to1),331 stroker for my 66 Mustang coupe Vintage racer.....I'm going to use a solid roller cam in the 550 lift range and a MSD distibutor,still undecided on the
oil pump,that's why I'm asking..... The guys that run these motors in the Vintage race series around here are about half and half on the oil pumps,standard vs. HV....I DO NOT want to be pulling a motor and tearing it down cause it ate a distributor gear.....I spoke with one of the top guys here running a 331 stroker and he uses a standard volume pump,shimmed the spring to give around 80 psi at anything over 3000rpms,at idle (1200rpms) it usually runs around 35 psi fully warmed up.... My present 351-W with a standard volume pump runs at 30 psi at idle and around 50 to 55psi at anything over 2000rpms,once the oil temp gets to 200 or above it "loses" about 5 to 8 psi across the board.....I'm using 10/30 Mobil 1
synthetic right now,in the past I used Rottella T 15/40,oil pressures were almost identical with either oil.....
Any and all info and suggestions are welcomed,if you have any hard data on this,please pass it along,right now,all I have to go on is what I have seen and that has varied quite a bit.......
David