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how come its 180 degs out of phase? I get this question all the time, well heres something I see lots of guys don,t understand ONCE YOUVE INSTALLED A CAM WITH THE TIMEING MARKS YOU MUST ROTATE THE CRANK 360 DEGRESS BEFORE DROPPING IN THE DISTRIBUTOR while its true that if the
timeing marks are possitioned so the crank is at 12 o,clock and the cam gear is at 6 o,clock that the cam lobes will be in the possition that fires #6 cylinder that HAS NO EFFECT AT ALL (on finding TDC,) for aligning the degree wheel with TDC,or THE timeing tab pointer, for degreeing in the cam, the piston passes thru TDC TWICE in every fireing cycle once on the fireing/power stroke and once on the exhaust stroke, the cam rotates at exactly 1/2 the speed of the crank so to make it easy to line up the marks they install it with the marks at the closest point 6/12 for easy indexing, rotate the engine 360 degrees to the #1 TDC power stroke and the crank gear will still be at 12 oclock 12/12 but the cam will be at 12 o,clock also, rotate another 360 degrees and your back where you started. its simply easier to index the cam at the point where the index marks align closely. look at how the cam lobes themselfs open the valves when the cam is just installed the #1 cylinder valves are slightly open and the #6 are closed per "Lunati" YES YOU ARE RIGHT - WHEN CRANK IS AT TWELVE AND CAM IS AT SIX THEN #6 CYL IS FIRING AFTER YOU LINE UP YOUR MARKS AND INSTALL GEAR THEN ROTATE YOUR CRANK ONE REVOLUTION AND THEN DROP THE DIST. IN - AT THAT POINT #1 IS FIRING

cam timing
BR>Explanation of Crankshaft timing marks: 0 - Indicates standard cam timing A - Advances the cam timing 4° R - Retards the cam timing 4°

BTW on some gears the (A) is a triangle and the (R) is a square

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