I have a 1979 F250 currently with a 300 straight six and C6 transmission.
There is a 1972 351 Cleveland available with a flywheel on it.

1. Can I swap out the 300 for the 351 by using a 164 tooth, 28 oz. flex plate for a '72 351C?
2. What torque converter would I purchase that would be compatible with the 351C and C6? I'm not sure if there are different splines on the pump.
3. Are there any modifications I need to make to the C6 (pump, etc.)? I plan on a rebuild with a shift kit.
4. Is there a difference in harmonic dampers between an automatic and manual transmission?

Thanks for your help.

 

1. yes
2. Stock engine, stock converter available at any parts house.
3. No. Unless you plan on upping the horsepower a bunch.
4. No
You will have to figure out the kickdown linkage. If the kickdown rod for that 351C is still around grab it. Otherwise you may have to buy an aftermarket cable type.
You didn't say if the Cleveland is a 2bbl or 4bbl engine. But in my truck which has a 71 4V, 351C and 79 power steering in it. The drivers side cast iron manifold would not work.

 

Thanks for answering 1-4.

Funny you should ask about the heads. It actually has 400 2V heads, casting date of April 1980. He does not have the exhaust manifolds. I would like to keep with cast iron to avoid longevity issues with headers. It also has power steering. Do you know what manifolds would clear the power steering?

 

The 2bbl manifold is a lot smaller than the 4 bbl so it might work. Also since you can use a set of manifolds from a 351M or 400 out of a truck they should be easy to find in a salvage yard near where you are located. The biggest problem I had with the 4bbl manifold was it came in contact with the engine mount because the Cleveland's deck height is around an inch less than the 351M or 400 which puts the manifold closer to the engine mount. Since Ford never put a 351C in a truck I used the engine perches and isolators from a 77 F100 with a 302. Here is a link to a good description of the engine perches. Comparison Photos of Engine Perches - FORDification.com

 

I realise this is an older posting however wanted to correct the notion that Ford never put Cleveland's into F series pickups,

Ford Australia installed the 351 and 302 (yes, a de-stroked Cleveland) into its 1974 -1984 F100's, 150.250 and 350 trucks as the only V8 option.

Australian cast Cleveland blocks, heads, cranks and 2- and 4-barrel manifolds were manufactured in the Geelong casting plant until 1982, the last blocks were used in 1984 V8 Falcon models.

Ford USA stopped Cleveland production in 1974.

Small block pattern C6's were used on 351 trucks from late 77 and earlier were C4 auto's or C10's a similar box to a C4.

Many of those trucks are still running around with their original Cleveland's and there is a large aftermarket industry around them over here.

Jus sayin',
Ross

 

We know that, but we aren't in Australia.

 

They did a ton of oddball stuff in Argentina and Brazil too IIRR
Brazil did not use much imported crude or gasoline for years and years and only ran alky
The Arab oil embargo of 1973 hurt Brazil (and all of us hard)
In Brazil it ushered in E100 in 1975 with the Proalcool program
Some of those motors might run pretty good on a dragstrip up here