Stock cam choice?

[Arne]

So here is a not so hypothetical question - assume that you are building a mostly stock L24 with a small valve E88 head. You have two cams to choose from, an internally oiled late L28 cam, or an externally oiled L24 cam. Which do you go with, assuming everything else is the same? Is internally oiled enough better to use that one rather than the possibly better cam timing of the early cam?

[jmortensen]

The external oiling system is superior in regards to lubrication when everything is functioning as it should, but either works fine unless you're really really pushing it. If one has a cam timing advantage I'd definitely go for that one. With stock I would think the one that is more retarded would be the one to have. The spray bar is more prone to trouble though, like the soldered joints in the bar coming loose.

[Arne]

I guess that's the nub of it, does anyone know what the timing differences (if any) are between the stock L24 cam (marked E30, as I recall) and one from an '83 NA 280ZX L28?

I've got two good cams to choose from, the one in the E88 that I'm going to use, and one in a P79. Both cams are in good shape, and I have all the matching rocker arms for both. If I go with the L24 cam, I'll replace the spray bar, even though the one on the head looks OK.

[jmortensen]

Here you go: http://www.atlanticz.ca/zclub/techtips/cam/index.htm

Looks like the early cam is ever so slighty more aggressive.

[Arne]

Perfect, Jon! That's exactly the data I was looking for.

Looks like the L26 cam was maybe even a touch hotter yet. But of the two I have the early cam would appear to be the better choice.

[beandip]

The cam from a L-26 I am told has the tallest lift of the all the nissan cams.

[Arne]

If the chart linked above is correct, the stock L24 cam has more lift on the intake valve than any other stock cam. But the L26 cam has longer duration and more overlap.

That said, it doesn't appear to me that there is a heck of a lot of difference between any of the stock cams.

[jmortensen]

You're right Arne they're all pretty much the same. Even a stock engine can do a little better and make a bit more power with a bigger cam IME.

[Arne]

Agreed, and I may go to a little hotter cam at some point. But if I can use one of the existing cam/rocker arm sets that I already have, that saves cash for other needed things. My first goal is to get my car back on the road, then I can worry about making it faster.

[ZSaint]

Arne: I just did the 4th cam change in my '71 240Z. I went with a .450-lift solid w/hydraulic lifters, (did not work at all) I then installed a turbo hydraulic cam w/hydraulic lifters, (worked great but ran out of steam at 5500) installed a Gude .480 lift hydraulic cam w/hydraulic lifters, (did not work/pumped up the lifters) and finally, I have installed the .450 solid WEB Cam w/solid lifter conversions. It will run the first time tomorrow. I simply gave up on the hydraulic lifters. Steve Epperly modified one lifter. Put the solid adjuster into the hydraulic base. It works! I took the rest of the parts to a buddy of mine and he did the machine work. I now have 12 solid/hydraulic hybrid ifters that will screw into the P90A head. I now can adjust my valves just like the P90 head. Hurray! I can hardly wait to get this thing running. By the way... Bill Gude is going to take the hydraulic cam back and replace it with a solid camshaft. I may change to that cam once I get the car running. I have driven the car 150 miles. It isn't even broken in!

[Zedrally]

Can you explain the advantage in having hydraulic lifters in a early L series engine?

I don't understand solid/hydraulic hybrid, surely they either are one or the other?

[Gav240z]

Here you go: http://www.atlanticz.ca/zclub/techtips/cam/index.htm

Looks like the early cam is ever so slighty more aggressive.

Thanks for that resource I'm sure it will be very useful to many people.

FWIW I went with a schneider 300F cam with all new rockers, springs, lashpads, and retainers. I can't wait to try it out with the triple 44 Mikuni's I purchased. :cheeky: