okay sorry for my stupidity but whats is a 351M? is it the same as a C or W engine. my uncle said i could have a worn out 351M out of an old 70 something pickup. i am considering buying a mustang and was wondering if this motor could be swapped in. i know there are lots of performance parts for c's and w's will they work for this motor. alos will it work for a car or is it more of a torque motor. thanks

 

Definitely a lot of confusion over the names, but the 335 series engine is comprised of:

Boss 302 (1969) was actually the first 335 using the heads that ended up on the later 351-C 4bbls

351-C or "Cleveland" made from 1970 -1974. This was the "premier" Mustang/Cougar high performance mill (used in other Ford cars too). It was made in 2bbl, 4bbl, "Boss", and CJ (Cobra Jet) styles each having its on unique head tuning. The C is known for being more Horsepower oriented than torque oriented.

400 (just plain "400") was introduced in 1971. It was the same basic block as the 351-C, but it had a taller deck height and different pistons and other internal head parts. I think this engine was made until 1982 and became a popular Ford Truck engine. The 400 was more "torque" oriented.

351-M (1977 - 1982) is rumored to have been a 400 that was "modified" and assembled in a place I believe was called the "Midland" plant in Michigan. Hence some people call it "Modified" (e.g., NAPA stores), and others call it the "Midland". But as far as I know, FOMOCO never designated what the "M" stood for. So to me, a 351-M is just that, a 351-M. 351-M was probably the most popular Ford truck engine, but it also showed up up in the biggger Ford and Mercury cars. The 351-M was more torque oriented.

The Windsor or "W" engine was Ford's original small block V-8 design that started with I think it was a 260, but I might be wrong. Windsor motor parts are generally NOT interchangeable with 335 series engines. The first 351-W was made in 1969 in the "Windsor" Canada Ford plant. It is still being made today, but it is in very few production vehicles.

For today's applications, the 351-W is probably the most popular Ford small block that can be easily built for hot rodding. But it also works in trucks, too. The 351-C was designed for NASCAR competition. Parts are a bit harder to find than the W, but this is a BEAR of a racing engine IMHO. The 351-M and 400 are torquers for sure, but a lot of "C" parts are not interchangeable with the 351-M/400, but a good handful are.

 

This is treading perhaps dangerously close to the line on not discussing "what the M means," but I wanted to note that the plant in Michigan where many 351M/400 engine components were cast was the Michigan Casting Center in Flat Rock, MI. I've never heard of a Midland plant.

I have some more info about the 335-series engine history, focusing on the 351M/400 engines, on this page:

http://home.earthlink.net/~bubbaf250...history01.html

 

Thanks Bubba!

 

thanks for all the info guys. so this motor is more of a torque engine. anyone have any stock horepower and torque numbers? i still wonder if it would make an okay motor for a mustang swap?

 

Here is some more history I found when deciding what to do with my 351M/C6. http://www.projectbronco.com/History..._ford_351m.htm

 

For a Mustang I would use a 351C or 351W.

 

If the 351M engine was discontinue with the 1982 models,
what designation is my 351 in a 1983 Club Wagon, build date
of Oct. 1982???

 

That should be a 351W.

 

1yamman350,
What year Mustang are you buying?

 

i would like to find a 67 or 68.

 

1yamman350,
I know a guy that had a '65 or '66 with a 351Cleveland "shoehorned in". I say shoehorned because he had to cut holes in the inner fenders to be able to change some of the spark plugs. The 351M has a taller deck height than the Cleveland. This added deck height also adds width to the engine.
So fitting a 351M in the car will be a tight fit. Although I think some of the '67 & '68's may have come with 360 or 390's, these may have been in the GT 350 & 500's, which could have had the modified shock towers installed. My dad had a '68 with a 302, putting a 351M in it would have definately been tight. Personally, I would stick with a 302 or 351Windsor. Hope this helps. Lee