351/400 Question

Buff · Jul 7, 2004

Hey, I have never understood what it means or what it actually is. Will someone please tell me or give me a link that will tell me? Is it not as strong as a Cleveland or a Windsor, but it can be built into a 400?
Thanks

freak · Jul 7, 2004

The 351M can be turned into a 400 by simply changeing the crank and piston's,that all.They share the same rod's.As far as strength is concerned it all depends on how the person build's it.

davids78bronco · Jul 9, 2004

the 351M/400 is a small block with big block transmission bolt pattern

Txquadhunter · Jul 10, 2004

http://www.projectbronco.com/Technical_Art..._the_rumors.htm

freak · Jul 10, 2004

The 351/400 has almost the same outer dimension's as the 460.It's not considered a small block,it's one of them they don't know for sure what it is motor's.

custom_78 · Jul 11, 2004

The 351 Cleveland was used in racing back when it was being buit. The blocks are a little diffrent from the Modified. The 351 Windsor is a completely diffrent engine than all of them. And as far as strenght goes Freak said it.

BLUEovalBELIEVER · Jul 25, 2004

tell the man the truth the 351m and 400 are money pits,please don't waste your money on one fords biggest fu#% ups
get a windsor,460,hell even a 390 is better than a 351m or 400

mcraesn · Aug 7, 2004

The 351M and 400 were designed specifically for the trucks. It really is not that bad of a motor if you build it right. The only thing is that there is not much after market stuff for them and what you do to them will cost you in fuel. One of the most helpful web sites to check out is www.projectbronco.com

davids78bronco · Aug 11, 2004

mcraesn said:
The 351M and 400 were designed specifically for the trucks. ...there is not much after market stuff for them and what you do to them will cost you in fuel.

None of that's true at all. Too many close-minded people shoot down using a 400 for anything other than a boat anchor. But hey, those are your opinions

4xfan78 · Aug 11, 2004

I agree with David I think that the m's are good engines. Even better if built right. Mine (351m) got around 12 mpg's up until it blew up.

stinger · Aug 15, 2004

I had 178000 on my 351m when i finally blew it ,gave me the reason to put in a 460. man i miss that truck

highboy73 · Aug 18, 2004

ya'll crack me up talking about the 351 m likes it buddha or something,times have changed get used to it in there time they did there job if you still choose to run an outdated powerplant that's your choice,but to tell me that you are effiecent with a obsolete motor with some 4bbl bolt ons is crazy.
welcome to a new generation EFI carbs are out been out.computer management is the way to go on any motor you should think of things to make you truck better and more efficent not just a low compression over cammed and carbed gas gussler.
good luck whatever you decide to do but building a motor that came stock is not showing you are a good craftsman,custom fitting in a new engine and drive train is.
it takes no special talent to rebuild something stock.

hawk2100n · Oct 13, 2004

you are totally right highboy, but in the end it all comes down to money. $-) going from carb to FI cost money, probabily more money than the gas you would save. How much you want to spend really limits it. carbs arent totally outdated though. they are still in still ultra popular in small planes. like cessna 172's and others. but Chevy never got 27 mpg's out of a corvette with a carb. i am shocked by that number. the new corvette with the ls2 (400 hp) gets 27mpg on the highway. wow!!

coop7379 · Oct 15, 2004

i agree that you can never get great gas milage from a 351m/400 and that they are realy hard to find after market parts for. however the after market parts on my friends and my 79 broncos with 400S only got better gas miladge. my friend more than doubled his gas milage with a new carb, pistons, intake and heads. he was getting 6 and his bronco is currently getting 15 mpg. the statement that they where weak engins also i do not agree with. yes their are many engines that have more power/ torque but their are just as many if not more that have significantly less than a 351m/400 also

utfish · Oct 29, 2004

Go to Bubba's M block workshop for a detailed explanation of 351M / 400M engines.

http://home.earthlink.net/~bubbaf250/

Ziggy · Dec 16, 2004

There are pro & con's to every story. EFI gets you better gas milage then a carb, the 351/400M are strong if built right, computer gas management, carb-less to go wrong. Me, I like my 351M, has been reliable as hell, gets great gas mileage, easy to troubleshoot problems. My alternator took a crap in the middle of nowheresville and I was able to drive 50+ miles on just the battery. Try that on an EFI engine with an electronic fuel pump. I see more posts asking how to troubleshoot EFI systems then I do for carb related fuel systems. Some times "new and improved" isn't all that it's cracked up to be. But, these are my views.

4xfan78 · Dec 16, 2004

Some of us are just "old school". You can put fuel injection on a 351-400m I have seen it on a 351c that was in a pantera.

Billz4x4z · Dec 17, 2004

kids and gas mileage....hmmmm want gas mileage get a VW....351M/400...I personally built a 400 that put quite a few big blocks on the trailor.....and as far as efi goes you can get a edelbrock tbi system if your really lookin for fi.

Billz4x4z · Dec 17, 2004

I am going big block in the near future,not because I dislike the 351m/400 but I'm lookin for a engine that will rev higher

highboy73 · Jan 3, 2005

and the debate is still going on.Ok fine I have had a couple of them in the past and yeah they can be built for power and reliability.what I keep saying is why?
carbs are great too I still have a bunch of them laying around holding paper down.
no for real if it's not worth it to rebuild it don't,and if you got the money to blow on a rebuild like it would take to get a powerful reliable 351m/400 why not just spend it on a donor truck and get everything?
oh yeah sorry to offend all of ya'll 351m/400 fans,I used to be a big one too