351m ? good engine for fox

4rdnut said:

351m and 400m motors are boat anchors. The M motors have staggered rocker arms and valves not inline like the windsor engines. The M motors weigh just as much as a 460 engine so it makes more sense to put a 460 crate engine in the mustang then a 351m motor. I had a 400m in my 77 t-bird with a two barrel and it sucked gas and had zero performance. I put a frpp 460 crate engine in to replace it and i got the same gas mileage with almost three times the horse power and with the aluminum heads and water pump and intake and shorty headers, not all that heavy cast iron, it actually weighs less than the M motor. Also certain year M motors crack in the lifter valley, you look for a date and foundry symbol stamped on the block to confirm the bad block.

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my name is Rowdy, a friend of Fastdriver's. we met in iraq and chatted engines every night instead of fighting bad guys..

anyway, the cleveland has a 9.2" deck height with just a tad under 2 3/4" main bearings. the winsdor has a 9.5" deck with 3" bearings.
they both have a 4" bore and 3.5" stroke. the windsor has large bearings, so it has more resistance than the cleveland for higher revs. of course, most know about the canted valve design of the cleveland and its superior flow to anything ever made (except maybe boss 429 heads or 426 hemi's, but they arent small block).

introduce the ford 400. the 400 shares the cleveland design with the front timing chain and whatnot and bolting accessories. there are 2 main differencs. the 400 uses the 3" bearing as does the windsor, but the block was redisigned and extended to the 10.3" deck height as the 460 big block is. so u get small block bore with big block stroke capabilities. tim myers makes (or distributes) 4.250 stroke kits for these engines making a 434 stroker. they are topped with cleveland heads, so you have a WIDE selection of HIGH flowing heads.

now, here is the kicker. presently, there are only a couple of intakes made for this beast...luckily, there is a small adapter...
Intake Adapters
that allows you to bolt any (within reason i guess) 351 WINDSOR intake to this stroker beast. this means the ground stomping torque of a 4.25" stroker combined with the smooth idle and torque ranges found with fuel injection.

another difference between this block and other small blocks is the fact it has its own style engine mounts AND it bolts to big block transmissions. they were heavy duty and used the c6 extensively in the big station wagons and trucks.
parts are a little pricy, but alot of companies are starting to come back to making cleveland parts. here is another thing about them, they use the same distributor as the big block.

reason they were considered dogs was ford dropped the compression and went through tough times with their emmissions back then and the motor couldnt run with 8:1 and smog heads.

now, about the head style.
if you want alot of knocking and pinging, the standard 2v (american) head is there. they came with 2.05 intake and narrow cross section in the intake runners, which wasnt bad...but they had crappy combustion chamber design. the 4v (302 boss or 351 c HO and CJ jet) head has outstanding combustion chamber (quench) but they came with 2.19 intake valves and the ports are SO large, they really support 408 stroker motors better cause they can suck a volkswagon down the intake.
we stopped building the cleveland in 74 with the 351m/400 running till around 80 i think, but australia didnt stop production until WAY later and they redesigned the head locally to take merge the 2 designs...closed chamber quench chambers, AND the 2v intake runners. there are web sites i can show you that sell australian 2v heads (great cross sectional area in the runners, closed quench chambers, canted valves and 2.05 intake/1.65 exhaust valves) for like $500 USD a pair. they are cast iron and look bone stock but provide MASSIVE low end torque. put them under the grinding wheel and clean em up a lil (or more as desired) and watch them perk up.
the 400 uses cleveland heads, pan and exhaust, big block distributor (same as 460), so if u wanna build a nice long stroke for the mustang, 4.25 stroke gets filled REALLY freaking fast through cleveland heads, ESPECIALLY under a moderate 5 lbs of boost.

the 400 ford is in NO WAY a slouch. my dad and i built on back in 84 i think with flat tops, a good cam and good dual plane intake/exhaust and stuck it in his 80 bronco. in 4 wheel drive, we smoked all 4 tires quite a few feet before the big 35's bit into the pavement and lunged forward (breaking our necks in the process..i just got out of the cast 2 weeks ago..lol)

think about what you want..long stroke for ass stompin torque or shorter stroke and smaller bearings for high revs?
you can build a nice stroker out of the 351c block or the 400m block. the 400 m would require the intake adaptor, but would allow you the use of SEVERAL thousand intake choices from the 351 windsor so all your factory fuel injection could "in theory" bolt right up (minor porting required to match the intake-head) and all the technology in distributor design will modernize this engine (when stolen from the 460).

now, you can build a windsor for cheaper, but if u tried to match the stroke, your rod ratio would be on the ragged edge. the 400 has .800" taller decks which swallow stroker cranks and still leave you with a good ratio so no unneccessary strain on the side of the block (wasted torque and wear).

back in the mid evil times, one of the last and best swords ever made was a "hand and 1/2" sword. it had the balanced blade of the long sword but the hilt of a 2 handed sword...and it was called the "bastard sword". well, i think this engine fits that bill.
you want a budget truck engine or muscle car pusher? get that 400 block, bore to 4.030 to unshroud the valves, buy the 351 2v aussie heads for $500 and clean em up, stroke it to a 434 with tim myers help and fuel inject it through a windsor intake. you would have great intake charge, 2.05X1.65 canted vlavles, 4.25 stroke, fuel injection and computer programming.
hell, put a nice thump cam or some low revvin monster torque cam and hold on. you wanna put an ati procharger on it? lord help u if u do...
change to a 114 lsa cam with stout duration to take advantage of the cleveland head, throw a centrifugal or turbo on it to fill the cylinders at high revs and itll idle like stock, but have gobs of power in reserve.
all this power, and it only weights 125 lbs more than a 302.
(i forgot, it uses the cleveland cam and lifters i am pretty sure)

i hope this info helps make a decision. if not, you are informed on some forgotten ford history. =)

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