The 'E' Type Forum

Hi All,

I have a cylinder head with the number EF 301 stamped in the top at the one end. how can I identify which engine this is from it has early triple SU's fitted.

Was hoping I can use on my 4.2 E type

Thanks for any help in advance.

Mark

That will be a casting number and is of no significance . The first thing to be sure of is that it is a straight port head - the guide to that is that all SP heads have the front plug immediately adjacent to the front wall of the head - others have a blanking plug between the spark plug and the wall. Then, you need to know whether it is an early short stud type head, or a later long stud head; both are interchangeable but the later head has 2 extra water passages at the rear of the head and these have to be plugged if the head is used on an earlier block .

Is there a number on the front wall adjacent to the spark plug ?

Hi Chris,

Thanks for the reply, I only have pictures of the head at the moment and I can't check the things you suggested, I did notice that the head seems to be painted Gold originally.

The reason I was trying to identify the head is to see whether the carbs that are fitted can be used, are all Jaguar triple SU's interchangeable or are things like carb spacing etc different?

I understand needles etc may need changing to tune properly.

Cheers

Mark

Mark : assuming that the carburetters are HD8, and that they do NOT have the auto choke which was fitted to those used on the Mark 10 , they are usable on any 6 cylinder E type. The 3.8 engines originally used 3 separate twin port manifolds, and these can also be used on the other 6 cylinder cars ( S1 4.2 and S2 4.2 ) but would be inauthentic . The 4.2s used a one piece manifold , and again are interchangeable although there are some differences in the thermostat housings etc . and also it may be necessary to close certain water passages in the head . This is very straightforward