In your message you write:
> I was wondering if anyone could help me with the choice of cam for the mini
> engine I'm building. The specification is;-
>
> 1275 bored to 1312 (+.040)
> gas flowed and polished head, planed to give 10/1 CR
> Standard Mk3 Cooper S valves with 140 lb. valve springs
> Twin 1 1/2 inch S.U's
> LCB exhaust into 2 inch pipe with straight through silencer
>
> I'm builiding the engine to use in hill-climbing/sprinting. I also need to
> use the car on the road occasionally, so a full-race cam is out. I've heard
> that the 731 cam is a good compromise, and that it works from 1500 rpm.
> Haas anyone had experience with this cam? Bearing in mind that the car will
> only occasionally be used for fast road work, is it possible to get a cam
> "hotter" than the 731, but still usable on the road?
Graeme,
since it sounds like you will not be using the car for much road work, I would
recommed the 648/649 cam. It will pull strongly from below 4000 to over 8000
should you choose to run that high. I only rev to 7500. You might also want
to use the Isky lifters and pushrods, which are lighter and stronger than
stock.
The car will still idle around 1500rpm or so with the 649. It is usable on the
road. BTW, I assume you are going to lighten the flywheel and backing plate,
this will improve your acceleration noticeably. The stock unlightened ones
are godawful heavy. I would also suggest modifying the SUs per Vizard's
recommendations to get better flow. High Lift rockers will also improve
things with only a little idle roughness as a result.
Oh yes, buy the short velocity stacks for the SUs also. Winner's Circle, near
Cleveland sells nice spun aluminum ones that will fit in K&N filter housings.
It also would not hurt to strap the center main bearing for reliability.
good luck.
jim fuerstenberg
186,000 miles per second, it's not just a good idea
it's the law!
jfuerstenberg@dcmdc.dla.mil or
xgg2356@dcmdc.dla.mil
The opinions stated herein are solely my own and not those of my employer.
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