Gear Driven Cam

Looking for war stories on the use of the gear drive replacements for the timing chain. In the thread about the new Quaife there are some comments on the whine of straight cut gears. Personally, I love the whine that the can am and similar cars have. Besides efficiency that is one of the reasons I am seriously considering using a gear drive replacement with the dogbone idler gears. If there is a reason that this is not a good idea please lay it on me. The major question in my mind because of the floating idler is the behavior of the mechanism at high RPM. Is there an RPM limit rule of thumb for these? I appreciate all comments and enlightenment!

Cause they are damn loud. I helped a buddy in VA build a Ford with these gears, which incidentally weren't too easy to get, and it was REALLY noisy. I can't imagine having it 4 inches from your left elbow.

In fact, I've seen them advretised as "noisy" and "non-noisy" versions so you can pick how loud you want to be.

Unless you are running a ragged edge high RPM motor then I wouldn't think they'd be needed. And even then a good quality double roller and gears will work.

R

[ July 24, 2002: Message edited by: Ron Earp ]

I put a gear in my car cause I wanted everyone to think I had a blower on it.
The sound was very similar at 1/10 the cost.
Eventually it did get tiresome and I yanked it.

MikeDD

Just bought a new book on building Windsor
engines, and skimmed it. The author's research
with various engine builders serves the
conclusion that gear drives should not be used
in engines that will exceed 7000 RPM or use
modern engine management with anti-knock
sensors, the vibrations from the gear drive
can be mistaken as engine knock, causing the
ECU to adjust an otherwise well running engine.
The book had some good info on L/R ratios
(the 302 long rod has the best, almost 2:1),
piston speed, valvetrain speed (this is why
302s can rev so much higher than other engines,
the valvetrain speed of a 302 at 8000 RPM is
less than a 351W at 6000!)

I'll have to dig up the title and author,
and read a little deeper.

Ian