oil pump drive gear bb

hi

what is the best gear to use for roller cam engine ?

brass ones seem to only have a short life running on factory brass bushing ?

where to get the part and cost ?

what will hold up here ?

Melonized gear will wear better.

https://www.hughesengines.com/Index...l1=T2lsaW5nIFN5c3RlbQ==&partid=28107

I've ran several Mildon and Mopar brand bronze gears oil pump drives with no issue, my pump gas duster had over 3000 street miles and hundreds of both 1/4 mile and 1/8-mile passes shifting at or above 7000 RPM
I do set the end play,.004 to .012, (less end play is better ) on all the motors I build and use roller cams in

hi

the one i am working on has app 4000 miles and only 6 passes at the strip ,

lookes like the base wears then the gear gets lower causing ware on the teeth .

teeth prob would not wear if gear did not drop , teeth have min wear at this point .

dont know how much clearance cam has but roller pattern on cam lobe i can see looks close to roller width . i did not build this one just trying to keep it together .

Sometimes they wear out and sometimes they don't. My guess is that it has to do with the tolerances of the block machine work but I could be wrong. Could have something to do with the cam material or the shape of the gear teeth. I don't think there is a universal answer since I've seen bronze gears wear out almost immediately on some engines while I've seen them last a long time on other engines.

Disclaimer: I have no personal knowledge on this. But the situation always seems to arise with roller cams. And the failures seem to be hit or miss, some live, some don't. I'm with AndyF, it has to have something to do with the block machining, I think it is the lifter bores. If they are perpendicular to the cam centerline, the cam can move forward at will changing the contact pattern between the two gears resulting in accelerated wear. If the bores are not perpendicular, then the cam would tend to be thrust one way or the other. If it's to the rear, life is good, if it's to the front, that won't end well. I've never put a roller cam in anything but when I do, I'm convinced the secret is controlling the cam end play.

The amount of power needed to drive the oil pump plays into wear. HV/HP pumps put more strain on the drive gear.

I would like to add to this. If you use a belt driven oil pump, either wet or dry sump, the gear wear problem is non-existant.
All you are driving with the gear is the distributor. No load at all. Whether or not the lifters are perfect or there is some small
degree of cam end thrust, there will be no appreciable gear wear if you are not driving the oil pump.

hi

not sure if it is a hv pump but psi is app 60-65 range .

the gear teeth dont seam to be the main prob , it is the gear face and the bushing that have the most ware .

something causing the shaft to press down on bushing face causing the 2 to chew each other up then gear drops allowing tooth ware ?

Check the distributor end play with it in the engine, pull up and down on the rotor shaft to make sure it has end play
If none fix that
You could use some stamp steel distributor spacers or multiple gaskets

like materials running against each other will chew each other up.
example : the bronze gear running against the bronze bushing in the block.
install a steel shim washer [.010 thick ?] under the distributor gear will fix that issue, but as Cab said, check your end play.