Originally Posted by Master Yodub
Incorrect. There is one version of the B20 head that has an 84mm combustion chamber.
Well, yeah, I can understand using one on that oddball head, but how often do you see those?
For the others with the standard 81mm combustion chamber, it just seems like something super-obsessive. What's the average displacement of a B-series combustion chamber (say, a PR3,) anyway?