This is my first time posting here, I've searched for the answers for this topic, but haven't found it so here's my question.

I have a '70 F600 dump truck with a 361, of course the exhaust manifolds leak and half the bolts are broken. After a lot of phone calls and late nights online trying to find new heads I found a profesionally rebuilt 391 longblock that I got for $850!! I've pulled off the oil pan and checked the crank and it's really a 391 and everything is new and machined.

Now I have the old motor out and have stripped it down. I wanted to use my intake manifold and carb on the new 391 but it has some different openings that don't match the heads. The 391 heads have a water jacket between cyl. 3-4 and 6-7 that flows to the exhaust manifolds, the old 361 doesn't. I assume I need a different manifold, is this true? Where would I find something like this? I've had a heard time finding this type of part for these FT engines. Also, regarding the water flowing to the eshaust manifold, I purchased a new set of aftermarket OEM style exhaust manifolds, but they don't have the water jacket ports to match the heads either, will they still work? What is the purpose of the water flowing into the exhaust manifold? Pre-heat, or cooling?

 

Hello- Welcome to FTE! Check with the guys in the FE and SD engine forums. Check out the list of tech forums we have here. There is a wealth of information and expertise here to help you. There are a number of links in my sig below to help you also. Have fun!

 

I think you may have a crossover/riser for the egr coming up the intake. Is the 391 a newer engine? It may have emission provisions that the 70 361 didn't. Did it come with an intake or exhaust manifolds? I would only think water to the exhaust if it were marine exhaust and that usually comes through hoses from their own pump. Does everything else on the intake ports, bolts and such line up?

 

Yes the rest of the ports and such line up. After looking at the casting numbers for the intake and old the old heads it looks like it may be a standard 360 motor.

The casting number on the intake is C9AE 9426 B.
The heads on my 391 are C7TE C.

Thank you for replying to my original post.

 

The FTs had a larger crank snout and balancer for running pumps and such. If you can compare the diameters where they go into the timing cover it may help. Your engne is still a good deal.

 

Now I just need to find an intntake maifold and 4 barrell carb.