Re: Comp Cam

[jlandry@domain.elided (John A. Landry)]

As the little green aliens inserted a searing hot probe into the sternum of
Michael Alexander <malexand@domain.elided>, a blood curdling scream was
heard...

>I had a 79 345 motor rebuilt by Anything Scout in the Bay area of Cali.
>Included in the rebuild was a 'RV type cam', which was supposed to be, in
>the old terminology, a high tech 3/4 cam. The RV cam came on strong above
>2500 rpm. It was worthless below that figure. I use my Scout for
>transporting hang gliders up a steep hill. It was great going uphill but
>there was absolutely NO compression braking for the descent. I replaced the
>cam with a stock cam and regained the compression braking. Keep this in
>mind if you decide to pop for a comp type cam.

That's interesting Mike.  I thought long and hard about whether to go with an
aftermarket RV type cam or just stick with the stock cam and after talking to
lots of people, I sort of came to the same conclusion that you came to... that
the stock cam gives you the best possible torque low down on the rpm band.

Since I use my truck for pulling a trailer with 3.54:1 and 31" tires, my rpms
stay pretty low and that's where I need the torque... not to *start* up in the
2500-3000 rpm range.  I generally drive pretty slow when off road and like to
just idle along.  I pull the trailer slowly over steep logging roads, etc.
When I presented this type of situation to John G. of SSS on Binder Chat one
night, he agreed that the stock cam is what I wanted.

Of course, if a guy were going to be doing the tractor pulls or mud bogs with
tall gearing and modifying the engine to handle higher rpms, then of course
you'd want a bigger cam to take realize full the benefits.  I also read
somewhere that a cam meant for higher rpms and greater lift generally requires
stronger valve springs.  This increases cam, lifter, rocker arm and rocket
shaft wear.  To me that was one more deciding factor to stay with the stock
cam and original valve springs.  I'm interested in maximum engine life more
than maximum rpm and power.

>The cam was removed after about a months worth of use. If you pay postage,
>it is yours.

I'm sure you'll find someone willing to take you up on your offer, but like
you, I'm going to stick with the factory cam.

Take care,

John L.
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