Originally Posted by: bigev 
Hi,
I'm a Valiant guy traditionally but now have a '76 F100. I had a 351C rebuilt for it some years ago.
I am currently looking to upgrade the motor and will be buying a new manifold. My engine builder said at the time that he thought it was a 4V but had no record of it and could not be 100% sure.
How can I identify a 2V vs 4V head without removing them? The motor I have is from an LTD, September 1975.
Thanks.
P.s. I mention the Valiant thing because all this 'new Ford stuff' is foreign to me as a result!
The 4V heads only go to 1974.
The 4V heads have a 4 cast in a corner of the head just near the rocker cover, early ones have 4 and then later they have 4 with a dot next to them, in that same spot early USA heads have a 2 or 2 with a dot.
Our Aussie made heads have nothing at all cast their and are only 2V heads and Aussie heads also have 302 heads and you can tell the 302 to the 351 by looking at the passenger side front of the head, down at where the head gasket meets.
The 302 and 351 1975 engines had Aussie cast and made heads but all the blocks were USA cast imported but assembled here, so if they are original heads they will be 2V Aussie heads.
One thing to remember is that Aussie made 302 and 351 engine all became what can be described as a 4V from Jul 1976 because they have a 4 Barrel carby on them and also called 4 Venture carby.
The 4V and 4V dot heads from the USA only had 4 Barrel carbys on them and the 2V and 2V dot heads only had a 2 Barrel carby on them.
The 4V heads only came to Australian Fords in the GT and GT-HO.
There is nothing wrong with 2V heads at all.
The 1975 LTD all came with 2V heads and a 4 Barrel carby.
