At 09:19 AM 2/20/02 -0500, Paul Osborne wrote:
>....I get a note from a person saying not to purchase a new cam but to
>have the old one reground. The old cam is of much better material than the
>new one will be and the regrind will be a better cam and cheeper.
IMHO, the only reason to have a cam reground is price (which can be a
powerful motivation), or if you're looking for some custom regrind
pattern. There is nothing wrong with the materinal used in new cams.
That said, you should also be aware the many so-called "new" cams are not
new at all but are reground from old cams. The success of regrinding a cam
is largely dependent on the after process heat treating. These parts are
surface hardened only and the hard surface is only a few thousandths
deep. As such, the part must be heat treated again after a regrind, and
the quality of the heat treatment has been questionable in recent
years. Not only that, but apparently it can vary considerable fome one
batch to the next, as the heat treating is almost always farmed out to a
sub-contractor, and the grinder has not so good control. You may find that
new high performance cams from Kent (and others) are actually regrinds (but
I couldn't swear that they all are.
That said, the one Moss is selling as "Fast Street Cam 222-270" is actually
a Crane Cams camshaft 340-0010, and is made from a new forging blank. The
main clue here is that it has increased lift from taller cam lobes. Most
other cams have lift equal to the stock cam, and to do the regrind they
have to be ground down below the base circle.
Find lots of cam information on the Crane Cams web site, starting here:
http://www.cranecams.com/master/toc.htm
Also find MG specific cam installation information here:
http://www.ntsource.com/~barneymg/mgtech/engine/en1.htm
Fun browsing,
Barney Gaylord
1958 MGA with an attitudu
http://www.ntsource.com/~barneymg
PS
Hint: That Crane Cams part can often be procured cheaper through a local
speed shop.
BG
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