rebuilding 400m ????????
Elder User
Joined: Sep 2003
Posts: 576
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You can just call it a 400, only the 351m is called "m" to distinguish it from the 351c and 351w. There's no other ford 400, so they know what you mean without "m"
anyways....it's pretty much the same as any other 70s engine. They've very low compression in stock form, you'll get a lot of gain going with better pistons, check out tmi in the sponsors. The stock heads are pretty ok for a low revving truck engine, you could go with some aussie heads if you're looking to improve. A good cam and timing set is a must. A 4 barrel carb, intake, and headers will also be a big improvement.
anyways....it's pretty much the same as any other 70s engine. They've very low compression in stock form, you'll get a lot of gain going with better pistons, check out tmi in the sponsors. The stock heads are pretty ok for a low revving truck engine, you could go with some aussie heads if you're looking to improve. A good cam and timing set is a must. A 4 barrel carb, intake, and headers will also be a big improvement.
Senior User
Joined: Nov 2007
Posts: 147
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From: ontario canada
the best thing you can do is take that gutless, rodkicking ,knocking piece of junk out and spend the same money putting a 460 in, NOTHING will improve a 400's durability so spend the money on something worthwhile!
Originally Posted by polky
im going to rebuild my 400m. bearings are bad. what mods are the best and proven to work? any and all suggestions will be greatfull.
thanks
thanks
Posting Guru
Joined: Jul 2006
Posts: 1,354
Likes: 1
From: America
take it easy pal....we all know you hate the 400...
and to polky, id keep going back in the 335 series forums and read away because theres a ton of information that you can pick and choose from. there probably isnt another place on the internet with more info on the 351m/400.
and to polky, id keep going back in the 335 series forums and read away because theres a ton of information that you can pick and choose from. there probably isnt another place on the internet with more info on the 351m/400.
Senior User
Joined: Nov 2007
Posts: 147
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From: ontario canada
heres some tips on building a 400, I wasn't able to keep 1 together but I have been known to push things to beyond their limits, make sure the main line is straight, spare no expense on the rods, good bolts, polish and magnaflux, start with the mag, forged pistons are available, still have a set of .030's, restrict oil to the lifters, you need the oil at the crank, if you can find some aussie heads use them, still have them here , the open chamber heads are detonation prone, use a performer intake and your choice of carb. Most importantly Never let it rev past 6500, they just won't do it for even a short time
MSEE
Joined: Apr 2004
Posts: 10,386
Likes: 35
From: Austin, TX
Originally Posted by 1EVILCREWCAB
the best thing you can do is take that gutless, rodkicking ,knocking piece of junk out and spend the same money putting a 460 in, NOTHING will improve a 400's durability so spend the money on something worthwhile!
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Cargo Master
Joined: Apr 2001
Posts: 2,364
Likes: 3
From: Eustis FL
Don't come into the 335 series engine forum and knock a 335 series engine... PERIOD.
It's like going into a chebbie forum and telling them all their chebbie stuff is junk (truth); They just don't get it, nor will they.
Coming in here to spout is indicative of a rabble-rouser, a s**t disturber of sorts. Why bother? You are wasting your breath. Do you think Tim would be spending so much time on these engines if he thought they weren't worth it? Then there are the Pantera owners who can't wait to get the 400 (with small bellhousing pattern) in their cars.
It's like going into a chebbie forum and telling them all their chebbie stuff is junk (truth); They just don't get it, nor will they.
Coming in here to spout is indicative of a rabble-rouser, a s**t disturber of sorts. Why bother? You are wasting your breath. Do you think Tim would be spending so much time on these engines if he thought they weren't worth it? Then there are the Pantera owners who can't wait to get the 400 (with small bellhousing pattern) in their cars.
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Posting Guru
Joined: Mar 2002
Posts: 2,070
Likes: 2
From: Boise, Idaho
I haven't yet heard of a place that will install oversize bearing in a C/M/400 and align bore the cam bearings. As I understand it, that's the way to cure the oil pressure problem.
I think the stock 351M truck cam was a good part. I would use one of those if it could be found. I'd use a 1971 351C distributor. I'd get a Maddog/RollMaster timing chain and degree the cam. Otherwise, give it a stock rebuild.
Edit: For some extra special omph, considering using 5.0 roller gear to install a roller cam. Especially if you get the cam bearings align bored.
I think the stock 351M truck cam was a good part. I would use one of those if it could be found. I'd use a 1971 351C distributor. I'd get a Maddog/RollMaster timing chain and degree the cam. Otherwise, give it a stock rebuild.
Edit: For some extra special omph, considering using 5.0 roller gear to install a roller cam. Especially if you get the cam bearings align bored.
Last edited by pcmenten; Dec 18, 2007 at 10:13 PM. Reason: Fix a typo
Senior User
Joined: Oct 2005
Posts: 163
Likes: 0
From: buffalo wyoming
speaking of stock 351m's. my parts truck hasa 351m with a whopping 277,000 miles on the original motor. still runs strong, only problem is missing teeth on flywheel that won;t allow starter to engage. I has been run on propane most of its life though
Senior User
Joined: Nov 2007
Posts: 147
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From: ontario canada
ok, maybe i've been a little harsh, a 400 will do a lot of owners just fine with a few mods, my experiences stem from builds that were a max power adventure, I have found the hard way that a 400 can't withstand more than 450hp and still be reliable, I can also rip a 429/460 to shreds pointing out their weaknesses, FE's, when was the last time you saw a 427 with a broken rod that didn't also take out the cam? I've had more than a few 302's come in the shop with blocks cracked in half, in my opinion, (opinion ONLY) it makes no sense to spend money trying to improve something that has no safety margin, my aluminum boss429 block has broken main caps, I passed the safety margin on it so now I have to go beyond, what was good for 2000 hp now has to withstand almost 3, but with the right mods it will survive; until I find the next weak link
Originally Posted by fmc400
That's not really true; there are a few oil routing modifications you can make that kick the 400's oil pressure reputation out the door. My 400 made it past 150,000 miles and still can romp around the yard, I don't consider it any less reliable than any other 70's engine. Except for a straight six of course.
Senior User
Joined: Nov 2007
Posts: 147
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From: ontario canada
with the right parts and some careful planning you CAN have both, the single best mod you could do is a set of aussie heads, these will not only increase power with more compression, you can advance the timing more without it pinging, which makes life a little easier on the bottom end, use quality parts for the rebuild , clevite bearings, felpro head gaskets and a good prep on the crank and rods. a high volume oil pump is a MANDATORY addition along with a good oil pump driveshaft. If you set a limit on what you want out of your engine and have the means and stick to it , your engine should last a long time. With my personal experience building these engines they are not capable of meeting my expectations no matter how much money and time I spend. I have a fresh set of aussie heads as well as a bunch of other parts for a 400 if you're interested, I know I won't ever need them
Originally Posted by polky
i'm not planning to make it a powerhouse. it going in a 79 bronco. i just want a little more power and very reliable. with gas prices who can build for horsepower anymore?
Senior User
Joined: Nov 2005
Posts: 429
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hi evil, paul k here, listen, its obvious to me you were here before me, and the vets know you. but even though i am dtermined to make our 400 run. my first try on this particular design. i have to ADMIT, i did not think you meant any real harm, BUT, i did think it was funny. you know why, i have lost a rod bearing on this motor, honestly on a 100,ooo. plus bottom end. but it did go away. i had to smile. stay out of trouble and throw the fire to that 460 (grin) paul kiernan
