11-10-2018, 08:54 AM
(This post was last modified: 11-10-2018, 08:59 AM by Ian Williams.)
It is the depth of the thread rather than the recess, the chamber shape appears to change subtly throughout the progression of years.
Looking at them all with some small modifications to the transfer port to raise the roof into the plug recess and a skim the IA684 would probably give the best performance, good flow and an element of squish.
Looking at them all with some small modifications to the transfer port to raise the roof into the plug recess and a skim the IA684 would probably give the best performance, good flow and an element of squish.
Black Art Enthusiast