Home

Tips and Tech notes.

There are a number of mods and quite a bit of debate about their value.   I believe a couple should be done on all FE engines but other knowledgeable people disagree.

I think other mods are necessary only on high RPM engines and again I must say that this too is not agreed upon by every one.

The oil mods I that I always do are:

Open up the oil pump to oil filter adapter pad gallery from 3/8 to 7/16 inch and smooth and round the opening on the pump end and both holes on the adapter pad end.   I also restrict the flow of oil to the rocker arms using #80 Holley jets under the stands.   I usually use a high volume pump.

The mods reserved for racing engines are opening the the oil holes in the bearing saddles so they are as large as the hole in the bearings, drill and tap all oil gallery plugs for screw in plugs, and change the jet size from #80 to #70 under the rocker stands. The reason for the jet size change is less oil is needed to cool the valve springs at the track; on the freeway they can get very hot during expended driving.   Here I always use a high volume pump.

Something I encountered recently was an oil pump with an output gallery of less than 7/16 of an inch.   Checked a couple of others and found they varied from 7/16 on a TRW to 15/32 on a Melling High Volume one.   Thus the stock oil gallery size should be 7/16 inch and there is nothing to be gained by going larger unless you pump's output passage is at least that large.   I see no reason why the pump's out put passage could not be increased in size however.

You should read these as well.

http://www.network54.com/Hide/Forum/message?forumid=74182&messageid=988498374

http://network54.com/Hide/Forum/message?forumid=74182&messageid=1000664223

http://www.network54.com/Hide/Forum/thread?forumid=74182&messageid=1006015915

http://www.network54.com/Hide/Forum/thread?forumid=74182&messageid=1005249325

This is how I drill out the passage from the pump to the oil filter adapter pad.

Note I drill the hole 1/64 inch larger in successive passes using 25/64, 13/32, 27/64 and 7/16 inch bits.   This allows better control of the drill and allows me to center the bit easier.

1. First I open up the hole in the oil filter adapter pad using a small grinding stone.   This allows the drill to easily be centered on the original 3/8 inch hole.

2. Using a 25/64 inch drill bit I start drilling the hole, stopping after the bit is about 1/8 inch deep.   I check the hole to see if the bit is centered and if so proceed to drill the hole.   If not I use the grinding stone to center the starting hole and try again.

3. I repeat steps 1 and 2 for each drill bit.

While I have opened this oil passage up to 1/2 inch in the past, the next gallery is only 7/16 inch so its really not useful to go over 7/16 unless you are opening that one also.