the FBO plates I have are totally screwed up. near as I can figure the slots are set up for .010" movement equaling a degree. this wrong. .0154" is a degree. .010" is close for the vacuum advance degrees. I measured and checked every way from sunday and they're just plain wrong. I did do some measuring and found a way to use some of the slots , but the plate shifts position at full advance that screws up the desired total. first time I got anything with FBO on it that was wrong. waste of $50.
Thanks for elaborating. I am surprised that their limiter plate has a large center hole, which seems like could allow it to flop around a bit.
I have seen this chart posted in several threads - don't know how accurate it is:
Modifying advance slots
Dist degrees / slot size
6.............. .340
7.............. .355
8.............. .375
9.............. .390
10............ .405
11.5 ......... .420
12............. .435
13............. .445
14............. .460
15............. .475
16............. .490
17............. .505
18............. .520
