Converting E31 head to internal oiling

[bob m]

I am rebuilding an E31 head with larger valves, etc. I am wondering if it is possible to use a later model cam and drill oil passages in the head. Anyone had any experience?

Thanks

Bob M

[Bambikiller240]

I have no experrience with doing this, but I do know that it can be & has been done by many people.

[Ed]

I think all you need to do remove the oil spray bar and block the passages. MSA sells the blocking plates.

[Black Beaut]

Are there any advantages to doing this? I've got an E88 I'm prepping and need to get a new spray bar and cam anyway.

Cheers,

Rob

[Gav240z]

You should make sure when you seal off the original oil holes they are pressure tight to keep oil pressure.

I'm not 100% sure about having to drill holes as I was going to have to go the other way back to an oiler bar to fit a camshaft i picked up but changed my mind.

There is not really a major advantage however to me it seems like a more efficient way of oiling everything up top

[kinfish]

If you are using the E31 head and mating to an original 2400 cc block you have a potential interference problem if exhaust valves are increased from the stock 33 mm dia to the later engine 35 mm dia. Adding a high lift cam aggravates the problem. Can be made compatible by notching the contact point on the rim of the block. Not sure what happens with the larger intake valves?

I upgraded my 2400 cc engine with MSA Schneider cam kit which is designed with internal oiling via holes in the cam lobes. Only mod required is to trash the external oil manifold and cover the two supply holes for same with block off plates.

[Chino 240Z]

Last month I replaced the oiler bar with another, since the previous one had the end (#6) cyl. almost apart. I guess this is common for the #6 oiler section to fall off. What is the thinking of removing the bar and blocking, taking away oilling from the top?

[Bambikiller240]

Craig:

In addition to removing the spray bar, you must replace the current camshaft with one that provides for internal oiling. (i.e. oil is pumped into the camshaft and each cam lobe has a tiny hole in it where oil under pressure gets squirted out to lube the rocker arms and everything else up in there.

Advantage is that there is no longer a spray bar to crack and fall apart, robbing part of the cylinder head of life saving oil.

[Chino 240Z]

Okay, once replacing the cam, is there enough oil pressure upstairs to run both oiling methods?

[Bambikiller240]

Generally, No. You must block off the oiler tube supply holes to maintain acceptable oil pressure.

(FWIW, all modern cars that I am aware of use the internal oiling camshafts)

[Chino 240Z]

I thought so, and I would think so too.

[dspillman]

I've run with both oiling systems for 3 years now in race enviroment "ITS SCCA" No problems with stock oil pump, turbo robs HP,.....180+ crank HP....

YMMV,

David Spillman