FE oil modification photos

[SFfiredog]

DISCLAIMER:
Because of my German heritage (overkill) I tend to go beyond what is required (anal retentive) and like to push the envelope a bit (mad scientist). Most of these mods are over the top for a street 390 or 428 that will see 5500 rpm. However, this block is for a customer's street 483ci tunnel port that will see 6500 to 6800 rpm and will hopefully make around 550 hp.

I chose this late 64 center oiler block because it had thicker cylinder walls than the side oilers I had to chose from. (these days, beggars can't be choosers when it comes to good 427 blocks) I believe that good, thick, stable cylinder bores in a center oiler 427 is better and more important than paper thin, flexing, unstable cylinder bores in the side oiler 427s I could lay my hands on.
The mods:
1) Enlarge the main oil passages from and to the oil pump.
In this case, Ford already did the work for me as the c.o. 427s already have the large, 1/2" passages. On non-427 blocks I'd recomend enlarging to 7/16" max due to possible core shift. The only work needed it to deburr and clean up the turns and match the oil pump outlet in the block to the oil pump. (see 2nd photo)

2) Align the main bearing oil feed holes with the oil slots in the main bearings.

3) Chamfer and deburr all the oil return passages in the block.
Get the oil back to the pan as easily as possible.

4) Shim up the pressure relief valve in the back of the block.
If you are using an oil pump with an internal pressure relief valve, shim up the relief valve in the back of the block 3/16"-1/4" to keep it closed. You don't want both valves dumping pressure.

5) (Herein starts the overkill) I cut the grooves in the cam journals .020 deeper and .010 wider to supply more oil to the main bearings. Center oilers don't require grooved cam bearings, side oilers do.

6) I added an extra 5/16" main oil line to feed the main oil passage from both ends of the engine. The AN fitting in the front of the block will attach to a -6 line connected directly to the main feed from the oil pump. (see photo)

I believe these mods will help keep the bearings well fed with oil.

I'll post more as the engine progresses.

--Mike

[SFfiredog]

nt

[Bill Kesner]

Mike....

Not a bad idea. I like it!

- Bill -

[Tom T.]

Mike,

My center oiler had some of these mods, and they helped. You really know your stuff!

TT

[Keithc8]

Most people pass up some good blocks because they believe they have to have a side oiler block. We are using the center oiler blocks in Red LeBlancs and his sons NHRA national record holding mustangs. We turn these engines 8200 to 8400 RPM's with no oiling problems what so ever. If the oiling system is done properly you will have no problems. These blocks are actually sleeved back to 428 bore size because they are running the 428/ 335 horse power engines with the factory steel heads. we are getting about 720 to 730 HP out of these with the factory compression of 10.8 to one and the original 735 carb. We can run a solid roler camshaft, after market intake and port the heads but have to have the original port volume. I agree about the better cylinders for better ring seal and HP. Good luck with your project and the 550 HP should be no problem. Keith Craft