My bike is a 57 FL that had 66 shovel heads and cylinders.I just got a great deal on a pair of S.T.D. 3 5/8 " dual plug panheads. I pulled off the cylinders and measured the bore which comes out to 3.45" and the stroke is measuring 4.5" Doing my public school math that comes out to a bit over 84 cubic inches. My pistons are .040 over. The head fits on the 66 cylinder ok but I have to ask the folks out their who have been doing this longer than I for an azimuth check.
Question 1: Will these heads work on the current 66 cylinders?
Question 2: Would you recommend upgrading to 80 inch cylinders?
Thanks in advance for any guidance I get.
3 5/8th inch heads on 74/80 inch cylinders
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RangerMedic94
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1950Panhead
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Re: 3 5/8th inch heads on 74/80 inch cylinders
Std FL bore is 3.437, 3.45 is .013" over standard.I pulled off the cylinders and measured the bore which comes out to 3.45
Std FL store is 4" so you have a stroker crank
I think so, however pan and shovel rocker arm ratio are different meaning you should check valve clearance.Question 1: Will these heads work on the current 66 cylinders?
No, I recommend ditching the shovel parts and getting pan parts.Question 2: Would you recommend upgrading to 80 inch cylinders?
Jerry