If the spit engine is like most: The cam sprocket has four holes but only two
are needed to bolt it
to the cam. One set of holes is 'straight' and the other is some small amount.
If you are 'a degree off' you
might experiment with this. The other trick which works on the TR-6 is that the
cam sprocket is reversible-
turn it backwards for a slightly different offset. You can make pretty fine
adjustments to the cam timing by
flipping things around.
Cheers,
-Erik
At 10:52 AM 2/11/99 -0600, Erik Bjorkner wrote:
>
>Thanks to all those who sent info on degreeing my cam for my SPIT autocrosser!!
>
>I was having a problem with power above a certain RPM.. thought it was the
>Stromberg and crappy exhaust on it.
>
>The cam was advanced about 10 degrees. I was going to advance it so the
>power was not above 6000 RPM's (cam card states good for 6300) but I decided
>to install it straight up or as close to that. It is now 1 degree
>retarded.. close as I could get it.
>
>I experimented with the degree wheel much and it turns out that one tooth is
>equal to 18 degrees. Therefore, one movement of the cam gear is about 4 1/2
>degrees. I had some positions which I doubled checked and I came up with
>different numbers.. now the queer thing is that I got these different
>numbers very constantly.. But he one it is set to now was always on the ball.
>
>One important item was my cam does not have the same slope before and after
>the lift (asymmetrical) and it was very difficult to get the cam movements
>to less than a thousandth but when I did the results were very good (less
>than 1/4 degree).
>
>I would recommend all degree their cams when rebuilding the engine.. took
>about 3 hours but it is worth it!!!!! TOOK A TEST DRIVE WITH A OPEN
>HEADER>>> W O W <<<<<
>
>Can't wait till next weekend for the first race with the new Supper Trapp
>exhaust and the cam retimed!!
>
>THANKS!!
>
>Erik Bjorkner
>Mobile, AL
>76 SPIT # 66 DP
--
Erik Quackenbush, V.P. Operations, Midwest Filter Corporation
1-847-680-0566 fax: 1-847-680-0832 http://www.midwestfilter.com
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