Technical Flathead Intakes

Do the flathead intakes fit all the engines from 32 to 53, I am looking at one in classified and the seller does know which one he has?

 

They will all bolt on the block, but there are other differences. Unless you are a Ford purist (for which there are many, many different ones) the manifolds break down onto three groups. '32-'41, '42-48, and '49-53. The differences between the two earlier ones are minor. The later manifolds ('49-'53) can be easily identified by the two large (about 1 inch) holes in the front of the manifold for the oil fill tube and the road draft tubes.

I believe the differences between the manifolds recognized by restorers is beyond the scope of this board. "The Ford Barn" or Early Ford V8 sites would be the places to go for that type of information. I would also be careful as I have found that people who don't know exactly what they are selling have a higher tendency to be "scammers" than someone who is knowledgeable.

For aftermarket manifolds, things are little different; they tend to be more universal but can have some weird tendencies. I have a late model Sharp 4 BBL manifold that has the bolt holes mis-drilled (holes in the manifold where there are none in the block and vice-versa). When I tried it using the bolts that would fit, it had several vacuum leaks. I had to drill out two holes in the manifold and two in the block (there were no cast bosses on the manifold over the existing holes in the block).

 

They will fit both early and late blocks, but my understanding is you need to install some sort of pcv valve on an early intake to account for the loss of the road draft tube used on a late model flathead. Speaking of the road draft tube, an early intake will need to be clearanced for the tube that is present in the lifter valley of a '49-53 block.

 

There are also locator pins in the block to align manifold '32-48. You'll need to pull them, manifold just slops around on the bolts after 48. The vertical vent tube in the valley (picture right above) will hit the early manifold, slight trim needed.

 

Thanks for the information guys, I will pass it along to the seller.