first i'll get off on he wong foot and say ya WRONG the difference b'twn 351m 400m is crank(stroked), pistions(compression height), balancer(this is up to debate it works and had the 28oz c-weight but the timing marks are wrong),and factory flywheel(all ford replacement fit either) since these are the only differnces itIS a 400m
which is almost a clevand engine taller deck, high-strenght light weight casting, 3 inch mains and others i forget
second all Modified 351m/400m where not made in clevland in fact it was made in clevand (casting mark of three c inside one another) and michigan (mark is an m over two c inside one another)use caution with engines from mcc before 77 as there were "problems"
by the way modified with 3 inc mains taller deck height and big block(sorry to use cheby terms) rather fe or 360,390,427or 460 bolt patern
as for going .060 over in a m engine unless ya actully using a c block and i missunderstood i would install a quarter inch firewall and bullet(block bit) proof glass windsheild because your engine will blow out i would stongly suggest sleeving that enigne or don't bring ya old lady to the track
power can behad w/this motor 400/485 for apx 2000 or i have seen a 800hp pull truck sportin a 400m

[quote]Originally posted by batered_bronco:
<strong>first i'll get off on he wong foot and say ya WRONG the difference b'twn 351m 400m </strong><hr></blockquote>

Someone show me the engine label that states
400M, there has never been an "M" after the 400,
because the 400 is the only 400 Ford has ever
built. The 400M never has existed, yet everyone
cclaims it to be an "M". Just to add a little
murk to the already muddy waters, when the 351M/400 were first designed, it had a true
smallblock bellhousing pattern, which was about
'71, in '72 the wonderboys at Ford changed it to
the 385 series bellhousing, but the casting still
had the ghost pattern for the smallblock in the
casting, and in '73, the SB pattern disappeared...

[quote]Originally posted by batered_bronco:
<strong>by the way modified with 3 inc mains taller deck height and big block(sorry to use cheby terms) rather fe or 360,390,427or 460 bolt patern</strong><hr></blockquote>

What is this about "FE OR 360, 390, 427"? Those (352, 360, 390, 427, 428) ARE FEs. Then the way you worded it FE or 460 bellhousing bolt pattern...a FE and a 385 series bolt pattern are different and will not interchange. However the 351M/400 bellhousing bolt pattern is the same as the 385 series (429/460)

And when was "big block" only a Chevy term? I thought the only Chevy specific terms were mouse and rat motors.

There was much wrong in your post, but due to your lack of punctuation it was way too confusing to try and figure out.

Ok, I think I'll throw another monkey wrench in the wheels...

Now, I have heard that the "M" stood for Midland. As in the Midland plant. That would throw the whole 400M (for Modified) out the window, now wouldn't it?

I have NEVER seen an "M" on the 400 until this thread. Please refer to what I said earlier...

[quote]Originally posted by BigBlockBabe:
<strong>the only engines to receive letters were the 302 - to differentiate between the 302 and 302C (Aussie engine) - and the 351 - to differentiate between Cleveland, Windsors and the M series.</strong><hr></blockquote>

[ December 28, 2002: Message edited by: BigBlockBabe ]</p>

Has anyone stopped to think what this argument is about?

A letter M?

Not worth arguing about if you ask me. <img src="confused.gif" border="0">

Me? Argue??

Hi I thought I would help out on the 400c 351m/400 dilemma. In 1971 ford came out with the 400. they advertised it as a 400c and built it for three years. In 1975 the Windsor plant was having a hard time keeping up with the demand for a 351w so ford put a shorter stroke in the 400 and gave it the designation 351m/400, which is 351 modified-400 modified. So there actually was a 400c, 351m and 400m. I have personally built a 400m for sand drag racing and really whooped on the Chevy and dodge boys, taking season 1st place 3 years running! I am now in the process of building a 1971 400c which I will be adding the 1971 351c 4barrel quench chamber heads and intake with adapter plates available through summit. the adapters are required because the 400c 351m/400 blocks had a 1.100 taller deck than the 351c. The estimated horsepower is between 500-550. Hope this helps. I have done a lot of Internet research on these motors and if you really look there is a ton of info out there. Happy motoring and remember old Fords never die they just go FASTER!
Mike K

The earliest the 400 was mass produced (that I have been able to find) was 1974, the 74-76 heads are also the most desirable...I have a set of 74's on my 400. I have a factory 1971 Ford engine manual and no 400 is listed as being produced that year. I have never heard of a 400C or even seen one and I have seen a few. Of course that doesn't mean I am right maybe they produced them for the Australian market? Can any of our Aussie members verify this?

Where did you get this info from, I'm curious?

Check out this link. http://www.projectbronco.com/Histor...e_ford_351m.htm

Hmmm...not exactly factual? Like this statement;



Actually I find this statement a little funny because anyone who drove these engines back in the mid seventies can tell you the 351C was one of the worst engines for fuel mileage ever built by Ford and it was more than a hundred pounds heavier than a comparable 302 Windsor engine and at least 50 pounds more than a 351W. The 351C initially got a bad reputation for spinning rod bearings because of the unrestricted oil flow to the lifter gallery which starved the mains and rods at rpm and Ford nearly had a class action lawsuit on it's hands because of it. As a matter of fact one of the reasons why the 351C was discontinued was because the Windsor engines outperformed the Cleveland engines in every area considered important for a street engine, fuel mileage, torque at low rpm, compact size and reliability. Canted valves are also a heck of a lot more money to mass produce compared to a simple wedge chamber with inline valves.

Here is a good link that gives weights for various engines.

Don't get me wrong, I am a fan of the engines (have a look at my photo album!) mainly because they were such a maligned engine by many enthusiasts because of the weak bottom ends and thin castings, but for a street engine turned under 6000 rpm they work very well. I went looking for my 1971 Ford engine manual last night to verify what I said about the 400 not showing up until later but could not find it, when I do I'll post what I find. I could be wrong about them not being produced in 1971, it wouldn't be the first time.

My 71' Motor's manual lists the 400 for 71' full size apps(260HP/400TQ and 9.0-1 comp). I also have an Encyclpedia of American Cars that shows the 400 starting in 71' as an optional engine. Is it possible that you, being north of the border, didn't get the 400 until 74'? Dan

I have a '53 F100 with a 400C+.030 engine. It is a 400C because it sports 351C-4V heads. The heads have hardened valve seats and stainless steel valves. The cam is a Crane H278-2. It also has Crane roller rockers, guide plates and hardened push rods, a high volume oil pump, Fluidamper, rear sump oil pan and flattop pistons. The intake is Edelbrock Performer dual plane, Carter 750 cfm carb, and Carter Electric fuel pump. The ignition is Mallory Unilite, Mallory Promaster coil, and Holley Annihilator CD unit. The exhaust is through Sanderson headers and Flowmaster 70 series mufflers. The tranny is a C6 w/shift kit and a high stall converter. The rear is a Ford 9" with posi and 3.25:1 ratio. The CR is near 10:1 even with the open chamber heads (75cc). This is a street driven vehicle.

You need to do more reading before you take everything Paul writes as fact. There's alot of stuff on there that is purely his opinion.


And I really *hate* when newbies bring up OLD topics.

Gee, can I add my $.02 worth on the subject?

My dad has a 1972 Meteor Montcalm that he purchased new. It has a 400 engine. It was never advertised as a C or M when he bought it. He also has two Lincoln town cars with 400 engines. No letter there either.

I have always been told by Ford mechanics and busybody old ladies, that the following engines exist. I may be wrong.

1. 351W (windsor)
2. 351C (cleveland) includes Boss 351
3. 351M (modified)
4. 351M400 (400 converted to 351)
5. 400 (never mass produced with 4V carb or performance equipt. and never had a suffix letter added.

In my opinion (and it's just an opinion) the 351W is the best bet for build up, due to lighter weight and availability of performance equipt. It usually has better engine compartment clearance.

That might have been $.03 worth.


Sorry BBB;

I should have read you link before I posted. I deserve a whipping.

MY link? I didn't post a link. I just quoted buddy that posted a link from PJB.


You should get a whipping for attempting to be whipped ahead of 4JawChuck.