E31 head question

[Galaxybj]

I have an E31 head that has been rebuilt. Got it off EBay. It does not have mount points for the oil bar on the cam towers. They are solid, no holes. Has anyone seen this before on an E31 and should there be a concern? Is it possible they are from a newer head?

[superfunk]

Are there oil passages in the cam? If so then it has probably been set up to be internally oiled. Someone else could probably give you more information on that. I still run the oil bar

[jmortensen]

It is possible they are from a newer head. You can switch them out and get a spray bar if you prefer (I would). I'd be careful running an old spray bar though, as the solder joints tend to loosen up and the end of the bar falls off, so then the cam doesn't get any lubrication at all. When functioning properly the spray bar is the better of the two systems.

[Galaxybj]

There are oil passages in the cam, so all should be well. The cam has an "A" with long dashes centered on each side of it stamped on the firewall end and red paint by #2 valves. Any thoughts/knowledge on what year it came from?

[jmortensen]

I would guess that if someone changed the towers they did that when installing an aftermarket or regrind cam. You can look and see what the "A" cam is if Nissan made one, but I think it's likely not a stock cam. A lot of cam grinders will put a stripe on the cam or some other color mark like that. If you have a dial indicator you can measure the lift and multiply by 1.5 to find the lift at the valve.

[Carl Beck]

Hi Bill:

The Atlantic Z Club has a good list of OEM Cam's and Marking.

<a href=http://www.atlanticz.ca/zclub/techtips/cam/index.htm TARGET=NEW>CAM SPEC.'s</a>

Looks like the self oiling "A" cam came with the N42, N47 and P79 Heads before 8/81.

FWIW,

Carl B.

[Galaxybj]

Thanks for the link Carl. I think the cam that is in the head that was on the car is a "C". If that is the case I may swap them out based on the information on the spec sheet.

P.S. Sorry we couldn't link up when I was in Orlando the first of the month.