Xj6 straight port head on 3.4 mk2

(Jason pain) #1

Morning all. The head on my 3.4 has seen better days. I’ve got a straight port head from an xj6 and relevant inlet manifold. Is this a worthwhile swap? I’ve been told that it’s probably not going to give any increase in power, however that’s not really the object. It’s just that it’s in better shape than the current one. I do however have a set of 2" HD carbs that i could refurbish and fit at a later date. Your thoughts are appreciated. Thanks

(Peter Jan Rusch) #2

If you want to use a XJ6 head on the MK2, think about to plug the 2 extra waterways, at the end of the head, The MK2 block does not have these.
Also what carbs were used on that inlet manifolds of the XJ6.
Maybe 2" carbs do not even fit.
I have a SP head on my S-type, and it gave some extra torq at low revs.
But I do not thing anything wil be gained by using 2"carbs, except higher fuel use.

Peter JAn