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WERK I WERK I is offline
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Join Date: Jan 2003
Location: Wisconsin
Posts: 3,322
Originally Posted by les_garten View Post
Sorry, don't get this at all. Where your spark plug ignites is determined by ignition timing and is totally separate from CAM timing. Ignition timing is timed to the Crank. You can have either cam timed anywhere you want and the spark plugs will still fire at so many degrees in reference to the crank.

One of us is missing something here. How many CAMS have you timed? CAM timing is INDEPENDANT from crank and ignition timing. You understand that the distributer is driven off a gear on the crank, correct? No matter how bad you screw up your CAM timing, it is not going to change where your distributer fires your spark plug.

I'm missing something here, please re-explain?
You're pretty close to having it right.

1. Cam timing and ignition timing are independent of one another.
2. Cam timing is referenced in relation to the crank(i.e.TDC---cylinder 1 & 4)
3. Ignition is referenced to the crank (i.e. BTDC at cylinder 1)
'85 930 Factory Special Wishes Flachbau
Werk I Zuffenhausen 3.3l/330BHP Engine with Sonderwunsch Cams, FabSpeed Headers, Kokeln IC, Twin Plugged Electromotive Crankfire, Tial Wastegate(0.8 Bar), K27 Hybrid Turbo, Ruf Twin-tip Muffler, Fikse FM-5's 8&10x17, 8:41 R&P
Old 03-17-2008, 06:03 PM
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