Cary:
Lots of good cams out there. Generally speaking, you want lots
of lift and short duration for a fat torque curve down low. A higher
compression ratio is an easy way to get more torque everywhere in the
power band, so it should be your first move. If you have the block out
of the car, get the block zero decked before you do anything else. This
is superior to shaving the head, but of course requires you to get the
block to the machine shop, a formidable task.
When you select your cam, look for the lobe spacing angle (LSA).
Tighter lobe spacing moves the power band lower, at the expense of a
choppy idle. Also if you are going to be going with a free flow exhaust,
look for a dual pattern cam (longer duration on the exhaust than on the
intake).
The stock LSA is 110 degrees. This gives good mileage and a
smooth idle, but moves the power band up in the RPM range. The 150HP PI
cam uses 106 LSA and 285 degrees of duration. The 106 LSA pulls the
power back down into a more usable RPM range, but makes the idle a bit
on the beastly side (depending on where you set the idle speed).
A good design for a street torque cam would be 260-270 advertise
duration on the intake, with 5 to 10 degrees more duration on the
exhaust, and a LSA of about 108 degrees. If you are using the stock
exhaust, then the exhaust duration should be the same as the intake, or
very close. Get as much lift as possible, using high ratio rockers if
necessary. You will need high performance springs to accommodate the
extra lift.
You will find most of the cams out there are single pattern
(exhaust timing is same as intake timing). These are older designs and
are obsolete. But so is the TR6, and it is not surprising that little
cam development is taking place for our cars. You could ask someone like
Elgin to grind a custom cam for you...
Here is a web page that lists many of the suppliers and many of
the cam designs that are available. Elgin Cams in particular is worth a
look, as the owner races Sprites and is into British cars in a big way.
NFI.
http://www.hottr6.com/triumph/tr6cams.html
Cheers,
Vance
-----Original Message-----
From: owner-6pack@autox.team.net [mailto:owner-6pack@autox.team.net] On
Behalf Of Cary Henry
Sent: Monday, July 03, 2006 7:10 AM
To: 6pack@autox.team.net
Subject: cam opinions
While my head is off at the machine shop, I am planning on replacing my
stock cam with a more aggressive grind. I wil be using the car on the
street only, and am looking for something with a little more power and a
lower power band. The two cams I have found that best suit my needs are
the
Goodparts GP2 cam ($179) and the TS S2 cam ($125). I am curious as to
what
everyone's opinions are on these cams, and if there are any other good
cams
out there that meet my needs.
Thanks,
Cary
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