View single post by Jensen Healey
 Posted: 03-30-2007 04:22 pm
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Jensen Healey

Joined: 03-11-2005
Location: San Anselmo, California USA
Posts: 983

Hi David,

You will find it difficult to adjust the pulleys except in whole tooth increments. The factory moved the keyway on the pulley to create the various degrees.

Notice that the 110in and 115in are on opposite sides of the pulley. Each tooth of the 40 tooth pulley is 9^, but since the cams turn at half the speed of the crank, it represents 18^ of cam timing which is measured at the crank. The difference between 110 and 115 is less than 1/3 of a tooth.

The simple answer is you have two options: use the 110 pulleys if you have reground early JH cams (A907E0351Y) or purchase adjustable pulleys and time them properly to 104^.

For a full explanation of cam timing madness read this:

You didn't really want to know all of this stuff, did you?


Last edited on 03-30-2007 06:58 pm by Jensen Healey