This has probably been answered before, but is there a difference between early (say, 1965) F heads, and later (say, 1971) heads? I know the engines are different (135 vs 155). Are they swappable, and would there be any issues, good or bad?
Little Head Question
- Thread starter IDave
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IDave said:
Siamese port = early heads, pre 68 IIRC...
Not swapable IIRC, or at least not worth swapping.
- Thread starter
- #3
Not swappable at all? Or, could you put a later head on an earlier engine?
I'm pretty sure the blocks didn't change - at least the head interface. So you should have no problem putting a newer head on an older block. Seems like a good way to get more efficient breathing, factory 2-bbls and header availability.
Eric
Eric
- Thread starter
- #5
Interestingly enough, this old head has 6>1 headers on it. Look like the usual manafre leakers, but I haven't been able to convince myself there is a leak. There is, however, the fact that, in spite of being 6>1, they are rubbing a groove into the PTO driveshaft. So, they have a limited life expectancy in my rig. Can I attach the old stock (siamese?) manifold to a later head?
IDave said:
NO!
Manifolds will not swap. Period.
Heads will swap, but there are issues. Different head gaskets for beginners. Blocks are actually different heights, which affects the distance between the water pump and thermostats.
I've put a 67-73 head on an older block, but wouldn't bother swapping the other direction.
My .02
Mark
- Thread starter
- #9
Romer said:
Wait 'til I put up the photograph of the other end of him!
- Thread starter
- #10
65swb45 said:
Well, I just went out and held the older manifolds against the newer head, and I see just what you mean.
Does that bit about the pump and thermostats mean that you need a different thermostat for the different engines?
i just blew out the fiber cam gear on my 67' f moter bent some push rods, i thought about swaping for a newer head but you will neeed a new set of push rods and newer rocker armes as they are different. The water pump will be the same and so will the head gaskets. you will need a new intake manifolds and headers, also a new carb as most pre 68 f moters had a 1bbl carb. But after you drop 2000 on all these parts why not just go out and buy a rebuilt 2f and kragen for 1500.