2wrench said:
Randall: Also visited the cranecams.com web site
on finding TDC. I found it a bit confusing. It
seems to address degreeing (finding TDC?) of the cam.
The entire article is about degreeing the cam, only the short section on finding TDC is relevant to finding TDC. But accurately finding TDC is part of accurately degreeing the cam.<div class="ubbcode-block"><div class="ubbcode-header">Quote:]My read of the Bently Manual describes a method of
finding TDC on the flywheel first utilizing the dial
indicator, measuring twice the movement to the top the
number one piston by first rotating right, measure and mark;
rotating left, measure and mark; splitting the difference
and finally placing the final TDC mark right between
the two[/QUOTE]That's effectively equivalent to the procedure on the Crane Cams site. The only real difference is that Crane suggests using a piston stop rather than a dial indicator ... removes one potential source of operator error.<div class="ubbcode-block"><div class="ubbcode-header">Quote:] (and is this split measurement done with a tape measure or some other method?)[/QUOTE]A tape measure used with care will do. A degree wheel might be a little bit better, but not worth it for a stock setup IMO. (You don't get that much control over cam timing anyway.)<div class="ubbcode-block"><div class="ubbcode-header">Quote:]So, it seems as if crancame addresses degreeing the cam in situations other than an engine rebuild. Am I
wrong? Does degreeing the cam have to be done as
well after this first step of finding TDC is done
as described in the Bently Manual on the flywheel/backplate?[/QUOTE]For an ordinary 'street' rebuild, no need to 'degree' the cam, IMO. But racers like to be sure they are getting every last 0.1 horsepower, and so like to double-check cam profiles. Sometimes mistakes are made when grinding cams, and checking each lobe for timing and lift is the way to be sure yours is just right. Also, many performance cams aren't supposed to be set "straight up" the way the Bentley assumes.
But for a stock cam and a street motor, the Bentley procedure is fine.