The 351M/400 share blocks. The 351M/400 block has a deck height of 10.297"-10.302". The 351C has a deck height of 9.2". The 351W has a deck height of 9.48"-9.52". You CANNOT mill a 351M/400 block down to 9.2" or 9.48"-9.52".

There are no cheap aftermarket cranks that are worth having. If you want a light weight, stroker crank for a 351M/400 block, then you have 3 options.

1) Contact a good machinist to have him spec you out a custom crank and then send those specs and a lot of money to a crank company like Bryant or Eagle and have them mill you a custom billet crank. Then wait, and wait, and wait. I tried this, it's not as easy as it sounds.

2) Buy a 351W stroker crank and then spend several thousand dollars having custom pistons and rods made AND then spend a few months trying to find the proper timing chain set to install a 351W based crank into a 351M/400 block. Then wait, and wait, and wait. Oh and then send the crank back once or twice plus the pistons and/or the rods because one of the 3 companies you will deal with will make a mistake or 2. I did this and it will cost you about $10K in parts and screw ups because one or 2 of those companies will decide not to eat the bill for their mistake.

3) Call TMI and buy one of his kits.

Re-read my post on cranks and timing gears. The 351W crank snout is shorter in length than the 351M/400 crank snout AND the 351W crank snout is larger in diameter. The problem comes about when you are trying to fit timing chains. You need the 351C/351M/400 lower timing gear and it's offset spacer which just don't fit the the 351W style crank.

 

That would be Jon Kaase and he won the PHR-EMC twice with that motor. It was a 400 with CHI heads.

Like I said in my other posts, the 351M and 400 share blocks. There is no difference in the blocks, heads, intakes, carbs, etc. The 400 came out in model year 1971 as a replacement of the 390 in cars. By 1977, Ford decided to replace the old FE motors in trucks and Broncos so they dropped in the 400 and they destoked the 400 from 4" to 3.5" to create the 351M. This gave Ford 2 inexpensive to produce, easily interchangeable engines that could replace both the 360 and 390.

 

I'm glad this thread is turning up so much info - I had hoped it would.

Just as an update, I tracked down an older manual in my library of "Stuff I Played With Before" (I never get rid of old manuals!) and found the specs on the Cleveland cranks.

Short of building up the journals in an M block with a welder and having it re-machined, there's no way a Cleveland crank will run in it except by contacting Eagle and have the mains on a Cleveland crank turned to M specs (Maybe...). The reason being that "C" cranks have mains about a 1/4 inch smaller in diameter (2.7484-2.7492 ~vice~ 2.9994-3.0002 for M, 400, Windsor, 429, and 460). In terms of radius - it only amounts to 1/8th inch (0.125). New main caps can be ordered, and even 4 bolt mains adapted.

* The 302 spec (mains) is 2.482-2.2490 inches

Other curious data:
ROD JOURNALS
351W 2.3103-2.3111
351M 2.3103-2.3111
400 2.3103-2.3111
351C 2.3103-2.3111
429 2.4992-2.5000 *Can be cut down, but journal alignment/spacing is not known by me at this time
460 2.4992-2.5000 *Can be cut down, but journal alignment/spacing is not known by me at this time
*Aftermarket parts both forged and cast are out there

ALERT INFO for used car & scrapyard crawling:
1971 - 1980 the fifth digit of the vin code is the engine code
(it became all different in 1981)

VIN number example:
1S53F100001
RED character is the engine code

(CODE/ENGINE/Years found in)
Q = 351M ~1975-1979
N = 400 ~1972-1978

H = 351W ~1973-1979

H = Cleveland 2V ~ 1971-1974
M = Cleveland 4V (1971 only) *4-bolt main caps & GODZILLA intake and exhaust ports. Head material: Cast Iron. GUTLESS under 4,000RPM due to mass vacuum loss -
A NASCAR spinoff, maybe. The only way to take advantage of it would be extensive high speed running or as a blower engine. Heads can be made to fit 'M' *basically pointless

N = 429 ~1972-1973
C = 429 CJ (Cobra Jet) (1971 only)
J = 429 CJ Ram Air (1971 only)

A = 460 ~1974-1975
C = 460 PI (Police Interceptor) *found in '73-'76 cars only

Obviously any car with one of the underlined Engine codes in the vin is worth a careful second look...
I doubt you will find one in a boneyard that still has the original engine though.

-It's still good info to keep on a reference card in your wallet...

Another thing we should look at is engine number stampings. Heads have one set of markings, the blocks have another - we should identify them once and for all.

KNOWING WHAT WE'VE GOT OUR HANDS ON is the first step to figuring out what to do with it...

*I would also like to gather a chart or table concerning timing chain gear land diameter, "SNOUT LENGTH" and overall crank length and main journal spacing compatability.

All in one place...


PS: If I remember right, Jon Kaase used a cam that gave about 0.73??? lift...... Which is outrageous
2008 JEGs Master Engine Builder Competition at Pop Hot Rod
Anyone got a specs breakdown on that?
(I'm not a subscriber)