camshafts

[LeonV]

I'm sorry Leon, I was speaking of their size and fitment.

Ok. Saying that "cams '70 through '83 are the same except the turbo" doesn't convey that very well...

[siteunseen]

I have this saved in my links and it's the first thing that hit my mind, Motorsport! Performance Camshaft, Stage III, 70-83 Z/ZX Non Turbo - The Z Store! Nissan-Datsun 240Z-260Z-280Z-280ZX-300ZX(Z31/Z32)-350Z-370Z Parts

I'm used to common sense thinking people, me being from Alabama, not engineers, so once again I'll apologize...

[nuinqua]

I'm replacing my camshaft because it was running terrible and I discovered it was broken. Is there a proper way to install the new camshaft? I heard they could break if not installed properly. Thanks.

Edited July 4, 2013 by nuinqua

[lenponz]

The stamp with a "C" marking is what i use. Its off a 260 but it did have a bit more pep than an "A" cam.

Externally oiled..

Cam Mark A C A

Date all all < 8/81

Part # 13001-E4126 N3626 E4126

Intake duration 248 256 248

BTC intake opens 16 20 16

ABC int closes 52 56 52

Int center angle 18 18 18

Exhaust duration 248 256 248

BBC exh opens 54 58 54

ATC exh closes 14 18 14

Exh center angle 20 20 20

Lobe centers 109 109 109

Cam lift intake 7.35 7 7.35

Cam lift exh 7.35 7.35 7.35

Valve lift int 10.5 10 10.5

Valve lift exh 10.4 10.4 10.4

[Zed Head]

I'm replacing my camshaft because it was running terrible and I discovered it was broken. Is there a proper way to install the new camshaft? I heard they could break if not installed properly. Thanks.

The recommended way to install a used camshaft is to get everything else that was used with the shaft along with it. The cam towers, the rocker arms, the wear pads, everything. Keep everything in the same order and orientation it was removed and reinstall that way. Your camshaft might have broke because someone installed just the shaft in the old towers and it flexed and fatigued.

[nuinqua]

Do I tighten one tower at a time a little at a time evenly? I don't want to break the one I install. Thanks.

[Zed Head]

I'm not an expert, that's just what I've read. Other sources say never remove the cam towers. But almost everybody says to get the matching rocker arms and pieces, unless you want to buy new rocker arms. The key to knowing if the cam is installed correctly is if it rotates easily. Also, don't use the torque specs. in the "How to Rebuild..." book. There's a typo, it's too high.

Any idea why your cam broke in the first place? Is it the original cam shaft or a replacement?

[nuinqua]

Thanks, it was the original camshaft. Not sure why it broke. It broke about six months after I drove it to Las Vegas and back from Ohio.

[Jeff G 78]

Check your head for warpage. If the head was warped an a machine shop milled it flat, the TOP of the head will still be warped. A warped top will force the cam to bind and break. Run a straight edge along the valve cover mating surface and check all along between the straight edge and head with your thinnest feeler gauge. There should be zero gap anywhere front to back. If you don't have feeler gauges, shine a flashlight at the joint and see if light bleeds though anywhere.

I would not swap the towers. I leave them alone and just keep the cam, rockers, and lash pads together.