I need to know how I can tell a 351M400 from a 400 Ford?the engine came from a 1979 Lincoln.The guy said it was a 351 modified 400. looking through Egay they all say just 400 not 351 M 400.so does anyone know what would be in a 79 lincoln from the factory 351m or the 400.I don't know if it makes a difference but the Lincoln was built in Canada.I need to know so I can buy an aftermarket intake and a set of headers.I don't know about this crap Ford came up with, is everything interchangeable?I take it that the heads are clevelands 2V heads with a 400 block?so aftermarket valve covers from a clevland will fit?trying to get this motor done for my beater.
the 351M and 400 are two different engines, they are mostly interchangeable, the 351M has a 3.5" stroke, the 400 has a 4.0" stroke. it's pretty hard to tell which it is just looking at it....but they are the same thing as far as all the parts you mentioned.
as per my copy of encyclopedia of american cars 1979 lincoln came with 302 in versailes {110 wheel base} and the continental {120 and 127 inch wheelbase} came with 400 cid engines .. I hope this helps.... Bobby..
thanks for the help..that is what the one's on ebay said they had in them.don't know why the guy said it was a 351 M.guess he knows as much about ford as I do.just trying to make sure i didn't buy something only to find out it wouldn't fit it.thanks again guys
had a 79 Ford 3/4 ton pick up camper special with the 351m engine said so right there on the drivers side valve cover there was a large white decal with engine specs also on the radiator header I believe it read 351ci M400 its a destroked 400 was a good workhorse of an engine but they cracked heads alot if even a little overheated
I have noticed this a LOT on ford engines in the junk yard..........on 351/400m and 360/390 fe...........if the sticker is still on the valve cover the 351 or the 360 will have the displacement in liters for the small displacment then a slash and have the larger displacement engine in liters next to it.........on the larger engine400 or 390 engine on the sticker there is only ONE liter displacment listed on the sticker........hope this helps some.........other way is to physicaly check stroke.............
if the original sticker is still on the valve cover, it will state the displacement. I run a 400 Ford in my '82 truck F-150, it was a transplant from another older truck- and the sticker is still on it. although 400's have a bad rep, this one is an f-ing torque monster, with only a 2-barrel. I intend to rebuild/upgrade it some day. the only other way to tell is, take a spark plug out, and using a small welding rod or piece of close hanger, measure the piston stroke from TDC down to BDC, while turning the engine by hand with a breaker bar and socket on the balancer. closer to 4"- 400, closer to 3.5"- 351 that family of engines has really good cylinder heads- I flowed a stock pair and they flowed MORE than 360 HP stock Pontiac 400 GTO D-port heads. Intake flow was around 230 cfm- they are canted valve heads. good design- just overlooked mostly- the 351M/400 blocks are basically tall deck Clevelands with larger 3" mains- as compared to the 2.75" main Cleveland block. The Cleveland 4V heads will bolt right on- and Ebrock makes new 4-bbl intakes and aluminum heads now to match the higher deck.
REMEMBER......351W AND 351C OR M AND 400 M STUFF WILL NOT INTERCHANGE. You CAN put C heads on a W...but it takes a bit of work.
To answer the question, only the crank and pistons are different between 351M and 400 engines. So the advice to check stroke is the only way to tell - with a rod down the plug hole or pull a head and measure. If you only need to know for intake and headers, they're the same. Buy it for a 351M and if it's a 400 you'll be pleasantly surprised. They tend to run low oil pressure, but run that way forever. My rule of thumb - early 70's cars came with 400's trucks for some reason usually got the 351M's. The valve cover sticker that says 351M/400 also lists the actual displacement down toward the bottom of the sticker in either cid or liters.
In the fwiw dept, I believe part of the story about the 351M is that Ford made a lot of 400-M blocks (taller deck) and they did the 351M bit to use them up. The M's are Clevelands and the regular short deck Clevelands were still out there so that story makes sense to me. I owned a 77 Ford 3/4 ton 4x4 with 400-M. Stuck in a Crower Compu-Pro #2 cam, headers, Edelbrock Streetmaster intake (the fore-runner to the Performer?), 625 Carter 4 bbl, a touch of ignition re-curving - actually bother-in-law did that when he owned it, it was a drag racing curve that didn't work all that well. Once a decent street curve was in, the truck was a good runner with reasonable for the time mileage at 12 mpg highway. The most important part about building up or simply overhauling the 400-M and maybe the 351-M as well, replace the valve springs. Ford had a bad heat-treat and I broke a couple of them and bro-in-law also broke a couple. Crower springs cured the problem.
Chilton says they made both engines at the same time for at least 3 years, so that story sounds a bit flakey to me....
I can't remember where I read about the 400-M to 351-M engine, but I do remember the thrust of the article stated what I said above. It could have been the magazine writer's impression after he had the reasons for the 351-M explained to him. Read this for a little more info. http://www.projectbronco.com/History/history_of_the_ford_351m.htm Looks like the main reason for using the 400-M block to build the 351's was for both pollution requirements as well as having the larger bell housing cast on to the 400 - which made it the same for the 351 - for the heavy duty C-6 trans. Ford's engines of that particular era must have been interesting to say the least. They had the 400-M and 351-M along with the 351-C and the 302-W and 351-W. The W's slated for higher revving use in the mid size pass cars. With the info available nowadays, I find the 351-M blocks weren't necessarily a use-em-up deal due to too many 400-M's, but instead, a well planned step into a good engine for the pickups. Sounded like a good story a few years back though....
Some facts and some fiction posted above! I bought a brand new 78 Cougar XR7 and ordered the 351M, the 302 was the base engine and the 400M was also an option. Since I also ordered the Midnight Blue Pimpmobile package it came with a console shift. Come to find out after the tranny blew it was a C4 and NOT a C6. Seems that Ford did not have a console shifter for the C6 and cobbled in the C4 which was woefully overworked and undercooled. I never did look to see if the block was cast for the C4 or they used an adapter. However the option was available on 77-79 T Birds and Cougars so there are probably a bunch still in the bone yards if anyone is curious.
the 351m400 that was in my 79 f250 camper special had a 4 brl, carb but I got the truck used so don't know it was factory it was a factory intake though no adapters .It also had a heavy duty 4 speed truck tranny with granny low it would haul just about anything pulled like a mother!!and like has been posted always had low oil pressure but never a nock or ping.Lost mine because my stepdad overheated it badly and cracked the shit out of both heads.junk yard and machine shop both wanted big money for a replacement set because they were so hard to find good ones.I wouldn't hesitate to use another one of these engines if I found one in good shape I realy liked the one I had
good points- there are some casting number references that list specific 351M and 400 casting numbers. I got a block that had the correct 400 casting numbers on the side. We tore it down, took it to the machine shop. it turned out to have a 351M crank in it anyway. ditto- measuring the stroke is the best way. every old Ford engine I've ever seen running or owned myself, had low oil pressure. 302's, 351M's, 390's- and upon tearing them down, all had bearings to the copper.
It was a special bell housing, and was used in various Fords from 73 to 79. and the trans used was actually a C5, heavier version of a C4
thanks guys alot of helpfull info as always.the intake was what I was wondering about the most.thanks once again
You can make a 351M into a 400 by changing the crank, pistons & front balancer to 400 parts. The 351 balancer will work but the timing marks will be off. I changed my 351 77 F250 4x4 over to a 400 with an edlebrock streetmaster, 600 cfm Holley carb, heads milled .050 and an RV cam & duals. The difference was amazing. Not the greatest return for the money but I never had any engine problems at all with it. The 351 flywheel & clutch will work fine but the 400 clutch is bigger. This was in 1978, better parts are out now as far as intakes. I was a dealership mechanic and never saw a single cracked block, they do wear valve guides out. There is no difference between 351M and 400M blocks , heads, or intakes.
It's funny, this post is like 3 years old, but Mercman1951 and I were just talking about this... I bet these are really gonna take off in the next couple years, as the FE's and to some extent, the 460's are escalating in price... the trickle down effect, I guess. Like the 71 'Cudas brought up the values of the 72-74's (price one lately?) these engines are gonna be the next step for Fords. While the Windsor family has such a huge aftermarket that I doubt they'll ever lose popularity, there's gonna be guys (like me) looking for cheap displacement. And, I bet after you "desmog" these engines, they'll be pretty good performers, and most guys will give em away, as they have such a bad rep. My .002, Jay
good luck in finding speed stuff for the modified motors. they were not that popular only in the big cars and trucks. you can get an intake and maybe the rv style camshaft but no serious hot rod goodies to be found. the rods i know are longer in the 400m but not sure about the crank. some idiot pressed 400 rods on my Cleveland pistons and when i was putting it together i noticed the pistons coming out of the holes by about 1/2". needless i wasnt a happy camper.
The 351M has 3.50 stroke and the 400 has a 4.00 stroke. The 400M came out in 1972 and the 351M came out in 1975. The block of the 351M and 400M are .500 inch taller block then the 351C.
since this thread is about the 351m and 400 by any chance does anybody on the hamb have a rear sump oil pan and pick up tube for the 400 if so i need one for my project
Check out this site: http://home.earthlink.net/~bubbaf250/ While not popular motors, and a build tab close to a high perf BB Chevy, they have potential...
There never was a 400 4 barrel from the factory even though it was listed as an option in 77. I know this because I ordered a 77 F250 4x4 with a 4 speed and it came with a 351. You had to get the automatic trans to get the 400 2 barrel engine. See my earlier post about making a 351 into a 400. They are not a bad engine, just not huge power or mileage and very prone to pinging and EGR problems. Carry a spare ignition module at all times
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