Drill Out 390 Oil Passage? Yes or No? - Ford Forums

Flawebmaster · 08-15-2009, 11:24

My 390 will be strickly a street motor and will never see 6,000 RPM. My rebuild book says to drill out the passage in the block beween the oil pump and the filter adapter from 3/8" to 1/2". I will be running a solid lifter cam (stock 427) and have plugged the block passages to the lifter galley. Should I drill out this passage or leave it alone? Looks kind of small at 3/8" but I don't want to mess up the block. Thanks!

kdtrucker · 08-16-2009, 11:03

This is only my opinion.....The more oil you have flowing the quicker it gets to where it's needed and there more of it.

You can't saturate the motor, there's only 5-6 quarts and once it gets to the top it goes right back to the pan and srarts all over again.

Happy drilling!!!
oh yea,....don't foget to thuroughly clean out the shavings or you'll be building your motor twice.

George1861 · 10-15-2009, 03:45

If you block the passage completely, how do the lifters get lube?

kdtrucker · 10-15-2009, 07:43

If you look at the front of the block you can see the passage that goes from the oil filter addaptor straight up to the cam and lifter galley so don't close off the passage!!