Ma Mopar left a little to be desired when designing both small and big block oiling routes. Therefore, a number of experts through the years have recommended various tips and tricks to improve fluid flow to rockers, camshaft bearings, or main bearings.

The lowest hanging fruit would be along the lines of a bolt-on high volume oil pump. But getting a little deeper into the internals takes some actual know-how to make sure too much oil isn’t going somewhere while too little is going somewhere else.

Hughes Engines has this know-how in spades with decades of Dodge and Plymouth performance experience. When it comes to some of the more sophisticated need-for-speed mods, not only do they know how to do them, but they sell the proper tools as well. Oil passage reamers are a good example:

Big Block Mopar

Use these reamers to open up the oil passages from the lifter galley to the main bearing bores. It is common for these passages to be smaller at the upper end (near the lifter oil galley) than at the main bearing bore end.

Use a 3/8” electric drill to ream completely through to the lifter oil galley. Use the ¼” reamer (PN 8350) in passages #1, #2, #3, and #5. Use the 9/32” reamer (PN 8352) in passage #4 only.

Small Block Mopar

Use these reamers to open up the oil passages from the lifter galley to the main bearing bores. It is common for these passages to be smaller at the upper end (near the lifter oil galley) than at the main bearing bore end.

Use a 3/8” electric drill to ream completely through to the lifter oil galley. Use the ¼” reamer (PN 8350) in passages #1, #3, and #5. Use the 9/32” (PN 8352) reamer in passages #2 and #4.