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MMiskoe
11-16-2005, 02:13 PM
Just to help me get less frustrated while looking at my overhead cam V motor (Nissan V6), can someone tell me why the rule that allows offset keys to be used to return cam timing to stock limits you to the crank and doesn't allow it to be done at the cam itself?

I know there are very few V-6 motors being raced in IT, but this restriction sure puts us at a disadvantage. When you re-surface the decks of a V motor, you change the cam timing between each bank differently relative to the crank. You cannot properly re-adjust the cam timing w/ an adjustment only at the crank.

W/ very few cars in this situation & the ensuing fury that would be created by suggesting a change to allow cam timing adjustments at the cam, I am only looking to find out why it was written this way.

Matt

Knestis
11-16-2005, 04:41 PM
Pretty sure that the rule is there precisely to prevent changing the relative timing between two cams (a la VW 16v) - presuming that it would be easy to cheat by allowing cam keys. Sloppy between-cam timing on Miati is one of the speed secrets that Sunbelt was selling for their big money, at least for a while...

This is a classic case of the rules trying to indirectly enforce a rule that already existed, through specific limits. Kind of like the VIN number requirement. Regardless of what this rules says, it would be illegal to change the relative cam timing, just as it is illegal to retard the cam timing (relative to the crank) using the current key-at-the-crank-only limitation.

This limitation has the unintended consequence of punishing V6 cars without really tackling the issue at hand.

K