Modified just means that it is not a Cleveland or Windsor. Thats just the name Ford gave it. By the way modified has nothing to do with Fords newer "modular" motors like the 4.6 or 5.4

 

cool thanks ^^^^^^^
i heard that the 351m is a big block is this true?

 

The 351m/400 is a small block but shares the same big block bellhousing bolt pattern as 429/460

 

A 351m = a 400 that is destroked. (modified from a 400 to make it a 351)

The only difference between the 400 and 351m is the 351m has a shorter stroke due to the crank and the piston deck height is taller.

 

If you read a ford book from that era, it is actually a 351midland because that's what plant they were built in.

 

is there a difference in fuel consumption between the 400 and the 351. if there is, is there any major difference between a windsor or the modified for example horsepower, reliability, and of course mileage?

 

funny, I thought it to be a Modified Cleveland block....and thus have a Crap load of interchangeable parts......
I thought ford took a 351C made it taller, to fit 400 Cu., then also had it destroked to 351 for light cars ans trucks... there goes that theory .

is there a difference in fuel consumption between the 400 and the 351.

depends, but usually 2 or 3 Mpg seeing teh 400 is hungry...er

if there is, is there any major difference between a windsor or the modified for example horsepower,

yes, the 351m was a torque engine, the 351w was a hp engine

reliability,

depends

and of course mileage?

GOSH yes. main bearing #4...5 I forget, are last to get oil and usually increased mileage = decreases oil pressure ALOT sooner then a Windsor

and I think it goes along the line of 351m = torque, 351w = horsepower

 

a 351M is a 351M. No idea where the misnomer "modified" comes from.

351M/400 is correct.

 

Correct. It was simply a 400..which is all that Ford called it as part of the Cleveland or 335-series engine family when it came out in '71. A few years later (1975) Ford decided they needed a smaller-displacement version of their 'big' Cleveland, crudely destroked the 400 to 351 CI, and slapped an "M" on the end of it so it could be identified as different from the 'other' 351 that was in production at the same time..the 351W..and the one that had only a year before ceased production..the 351C.

'M=Midland'.??.LMAO..why does that keep popping up?...all of the blocks were cast at Michigan, Dearborn and Cleveland foundries. That one was easy.:toothless

 

I've also read that the M in 351M is just a M. that stands for nothing.

 

i would hesitate to say that the 351m is a torque engine and the 351w is a hp engine... ive got a 351w that makes an awful lot more torque than horsepower.

 

I would not hesitate to say yr right. Kinda hard to explain in an engineering sense (as opposed to a parochial sense) how two pieces of iron that each have 4" bores and 3.5" strokes are going to be much different at the end of the day..ain't it? In fact..it can be argued that the W, with its smaller intake runner volume, snaller head ports and smaller valves, is more likely to be the one with higher low-end torque, between the two. But that's just a wild guess..er..no wait...something just poked through my alcohol-ridden Alzheimer's-clouded memory..Edelbrock created the SP-2P intake manny for one reason: to reduce the intake runner volume and CSA on the 351M/400 (and a few other 'big breathing engines like those) to increase the bottom-end torque..making it more "Windsor like' in that sense.opc1:

 

I'm thinking with those gears you don't lock that up in 4WD too often.

 

sorry its been awhile since ive had a 351m. Ive upgraded to 410, and my 351w bko cant match it.

 

Not you Wurmb. SMurray says he's got 4.10's out back & 3.55 up front.

 

I accident clicked the wrong post #.
:rofl::rofl:I ment this Quote:

i would hesitate to say that the 351m is a torque engine and the 351w is a hp engine... ive got a 351w that makes an awful lot more torque than horsepower.

and then say

sorry its been awhile since ive had a 351m. Ive upgraded to 410, and my 351w bko cant match it.

but after reading how big wheels put it, kinda backed-up my statment, you can get more torque outta the m easier than the w.

and I would have to say its easier to say 351modified simply because it is a reworked (modified) Cleveland..this give me an idea!

 

IVE got the performer 400 edelbrock intake and edel 4bbl carb .

the engine was rebuilt and my mech beleives he did summin to it!
the son of a bitch is crazy strong .
now that the timing on the dist and vac are set this thing starts right up and idles good .
considering my truck has a lot of added metal stuff all around and a rail road rail for a bumper ,i thought it would be slow and heavy BUT NO ,it will burn the rear tire at a light its wierd ,,i almost cant beleive it ,its like a ****ing hot rod,ill take some video and youtube it ..

 

Seeing a vid of your rig doing a huge burnout would make my day.:thumbup

 

lol Screeeeeeeeeech BOOOOM lol Cleveland was the suck windsor is bleh Boss nice!

351 m is a 351m400 from my knowledge.

351m 400 was a torque motor because the amount of space in the combustion area.( Now I'm going to sound really stupid) Higher deck height means more actuall space. The displacement is the same because the piston is the same size and technically moving the same amount of distance therefore "displacing" 351 cubic inches per rotation of the motor.does anyone get what Im saying?

 

All three Ford passenger car & light truck 351 V8's shared the same bore & stroke. The difference is the rod length. The 351M has a connecting rod that is over 1/2" longer than the 351W. This has the effect of increasing torque output at lower speeds, with the trade off of larger rotating mass.

By contrast, the 351C had the shortest rod length of the bunch and smaller main journals, which made it a high rev engine.

The large combustion chambers and high deck height of the M series block makes building a high compression engine difficult. A 351M in stock trim has the wrist pin located almost 2" below the top of the piston. This is the tallest piston in Fords V8 lineup and it means that the piston has very long skirts and is very heavy. Increasing compression by increasing piston height has the effect of increasing piston mass. The pistons are already heavy!

 

I have done some reading and this is some information I will regurgitate.

1-The 351M/400 is basically a reworked Cleveland. Ford kept the 2bbl 351C open chamber design. The ports are still huge compared to the Windsor engine. I have compared them to the 460 heads and 351W heads and they are closer to 460 port in size and shape.

2- Ford made the bearings larger on the M versus the C supposedly to increase bearing life.

3- The deck height of 351M vs. 400 is the same. Was increased from the cleveland block for increased stroke. the only difference between 351M and the 400 is the crankshaft and pistons.

It is my understanding that 351C heads will bold up to an M engine, thus the popularity of Aussie 302 Cleveland heads.