4 replies to this topic

[TrackWeapon]

I've seen on the net that composite camshaft would have a lot of pro's;
-30-40% lighter, stronger, more precise machining, possibility of hollow camshafts without that much loss in strenght.

would weight of the camshaft have an importance like the weight of valve as??

another thing, I've only found informations but no company that make them, are they just uthopic camshaft or are they made for real?

[Wuzak]

I have an article in a magazine about a camshaft with adjustable lobes!!!

I haven't read it yet.

[Engineguy]

The term "composite camshaft" usually refers to a steel tube with near-net shape (usually) powdered-metal lobes slid on... then the tube is expanded in one of a few ways to lock the lobes in place, after which the grinding can commence. Many production cars use them; an example that comes to mind is the Ford 4.6 and 5.4 litre SOHC and DOHC family of engines.

You're not talking about composite as in carbon fiber are you?

[cartfan76]

The cams you speak of that Ford uses on their Duratec family of engines is a nice concept....but in the '96-'99 Taurus SHO it is not so good. The lack of rocker arms/lifters puts extra torsional stress on the drive sprocket and causes it to slip from its position over time. Go check out www.v8sho.com for more info on this.
I'm part of the lucky folk who got the problem solved before the "bomb" let go...

[McGuire]

These are commonly known in the trade as "assembled" camshafts, and I have been to this party. In one instance (names withheld to protect the guilty) camshafts were manufactured this way: the cam lobes were coined from steel plate (with a keyhole in the center for the shaft) and jigged up on a steel tube...then an oversized, hardened ball was forced through to upset the tube and permanently fix the lobes in place. Or perhaps not. Imagine some of the unusual problems to be identified and diagnosed in the field. Oh the fun.