Difference between 9a and ABf head?

Any one know if there are any?

 

A search produces:

http://www.clubgti.com/forum/forum_posts.asp?TID=6833&KW=dif ferences

http://www.clubgti.com/forum/forum_posts.asp?TID=19372&KW=di fferences

 

damn howd you get the search to work, when i tried it threw up an error!!

Thanks mate!!

 

You have to limit the search to 'topic titles only' as opposed to searching entire message texts.

 

Will have a few pics of my own kr head on soon, gonna cut one up and have a few more cross sectional ones that aren't on vortex.

 

If the 9A is 92ish or newer, it's EXACTLY the same as an ABF head. On the later 9A/ABF heads the combustion chamber is dished where as the KR /earlier 9A heads have more sharper sides to the CC.

 

Yup thats basically it.
Early KR 026/027 have larger inlet ports(well the divider is smaller) and smaller exhausts
051 kr 9a heads have smaller inlets(larger dividers) and larger exhausts
051 early abf same as 9a kr
053 abf same port design as 9a kr, but with a dished combustion chamber.

Just checked in the shed again, I have another 051 ABF with the dished chamber.
Non idea why, but could be down to where it was cast, you never know with those bloody Germans!
Edited by: Hotgolf

 

Bump for Ray.

 

Gotcha!

The dished combustion chamber will only be effective with an 82.5mm or greater bore diameter I presume?