Looking at fitting one of these cams and on Kent's website it suggests using either the CF6 or CF7 followers. The CF6 being 109E Narrow stem followers and the CF7 are 711M wide stem followers.
The stamp on my block is 691M 6015BA. Will the 711M ones fit or do I need the 109Es instead?

AFAIK the 691M block has the stronger main bearing caps like the 711M but uses the earlier (and lighter) narrow stem followers. Ring up Burton and they should know for sure.

681F uses the narrower followers.

not come across 691F.

It says it's a 691... are we talking about something else?

hmmm, you are right. safest bet is to measure the diameter of the hole in the block for the follower. I can tell you what the diameter of the 711 followers is should you want.


I believe the first two digits are the year the block went into production, 1969 in your case.