First, please don't flame me guys and tell me to use the search function, I've read for hrs on this already and I'm not new to forums or automotive stuff.......been doing mustang 302 stuff for 20 years and this is my first 351m, anyway

S o I just picked up a rust free 77 f-150 with a 351m.............had low compression..........motor is now out......and it's gonna need boring, I have a set of closed chamber heads I think to go on it......gotta get them from the guy who gave me the truck still...........Anyway, I was thinking of doing a 400 conversion......here are my questions:

1..All I need is a 400 crank and pistons correct?
2. I'm on a tight budget so if I ordered a decent rebuild kit for a 400 off ebay like such would all the components in the kit work with my 351m?
http://www.ebay.com/itm/Ford-400-6-6-Master-Engine-Rebuild-Kit-1971-1982-/260684195996?hash=item3cb1fd289c&vxp=mtr
3. Also, I've read about TMI and they recommend mods to the oil system? what are these mods/where can I find them/read about them.......as my 351m had low oil pressure when warm..also had 144k on it..lol

4. Would a roller cam conversion be worth while and if so what parts needed?

This truck already came with a set of rebuilt heads...not sure if they are closed chambered, eddy performer intake, eddy 1407 carb.......if for a little extra I can upgrade to a 400 I'd like to....I will be using stock manifolds and dual exhaust and a mild rv cam.......I'm not looking for massive power just more than stock. IT will need crank work and boring and head work, Basically a full rebuild and if I can upgrade to 400 stuff with little to no extra cost that is the goal, I need to keep cost down as I may flip this truck when done for some extra coin.

 

no info on this guys?

 

Welcome to FTE, sorry this isn't a busy section of the forum, good answer here can take a while. I'm not a 400 expert but I'll do what I can.


1. Pretty sure you'll need rods as well
2. Don't see why not.
3. TMI has a decent website, Tim Meyer(I think that's his name) the TM in TMI is also a member here with some excellent posts. The advanced search has an option to search the posts of one user, give that a try.
4. Only you can answer if it's worth while, you'd need at least a cam, lifters, and pushrods. Probably more but it all depends.

 

Rebuild kits like that usually include the low compression pistons, which is what most of these engines were built with.



Good cam info here, roller is good, but costs more. Frees up power and lets you run cams with steeper ramps.

https://www.fordmuscle.com/archives/...d400/index.php

This seems to debunk oiling issues:

Rumors & Myths

Bubba's M-Block Ford V8 Workshop

TMI site, but you have to joint pintrest or some other crap to see things:

http://www.tmeyerinc.com/

We usually don't do the "search it out" flame on FTE. I would recommend scrolling for several hours through this forum, and you will find a number of 351m to 400 threads.

Good luck with your project. You may get more replies as there are several active members with projects working or running 400s etc.

 

good responses guys....this helps a lot, I will call Tim this coming week as well and see what he recommends.

 

so it appears I need to check the casting code on my block..........as it is a 77 truck..........If my block falls within the casting code that leads to water jacket cracking......DO I need to look for a different block even if mine isn't cracked yet?? I don't want issues later on.

 

mrj46,

I don't think you should worry too much about the block at this point. I would think if it's not cracked by now, it should be okay.

Yes, crank and pistons are all that's required to convert a 351M to a 400,

Doubtful you have closed chamber heads because they would either be 4V closed chamber or Aussie 2V closed chamber. Either way you would be looking at a new piston designed for that head. The 4V would also require custom headers.

A roller cam conversion was worth it for me, simple break-in, more reliable, more HP potential, etc., but doubt it would be worth it on a vehicle you planned to "flip".

 

I'm not totally sure the block isn't cracked, I did a quick visual of it in my shop yesterday and didn't see anything, but number 4 cyl had evidence of water being in it as it sat for 7 years......rust crystals here and there and staining/etching on the cyl walls....could of been a head gasket starting to fail......the block needs to be magged.......but I was reading that some claim even though it hasn't failed that upon rebuild and torquing heads back down is when it could fail?? I most likely won't do the roller conversion but the block will need to be bored....hopefully a .030 will clean it up and I was figuring since it will need new pistons and crank turned , then why not do a 400 conversion............some say that the 351m block can't safely be bored .040?? and I haven't seen the heads the guy is suppose to give me yet, all he said was when he got them rebuilt off ebay 8 years ago is that they were an upgrade from stock and suppose to give it more compression. I saw them 8 years ago but wasn't learned on 351m's so it meant nothing to me at the time.

 

so it appears I have a clevland cast 351m there was a CF on the top ledge, so I SUPPOSE I'M fine to move forward..........also got the heads from the guy today and they have the tags still from when he bought them off ebay, They say 351c 2 barrel heads and are open chamber of course with all new valves and valve job.......they have a D1 casting = 1971?? Can I use these clevland heads on this 351m/400 build??

 

Sorry, I'm traveling and haven't had time to respond. On the oil pressure see this active thread, and Post 22: https://www.ford-trucks.com/forums/9...l#post15413693. And, don't forget Tim's modified cam bearings.

On heads, see the active thread about 400 rebuild part 2. I have a post in there (#18) about heads, etc. But North American 2V 351C heads are the same as all 351M/400 heads. https://www.ford-trucks.com/forums/1...round-2-a.html

But, the only diff between a 400 and a 351M is crank and pistons. The rods are the same.

 

so I found this quote about 351c/m heads.......is this just some high performance guru spouting crap just to get you on the HP train?? Do I have to be concerned it'll detonate?? according to him it's inevitable...............




"Poor quench and chamber irregularities that cause spark knock make the two open-chamber heads unacceptable for a high-performance Cleveland. They spark knock when you start the engine and they knock under hard acceleration, which makes them a poor choice for any Cleveland engine including the 351M and 400 engines. There’s little or nothing you can do with these heads to gain performance or prevent spark knock. I’m puzzled every time I see these heads used for a magazine or buddy’s project because they are such a poor cylinder head. Considering the great wealth of aftermarket and Aussie iron heads available for the Cleveland, there is no reason to ever use an open-chamber head."

 

I have a D1AE-A1C Cleveland heads that are fully rebuilt with all new valves......... found this:
<table class="styledtable" style="width: 100%;"><tbody><tr><td>D1AE-A</td><td>Cylinder Heads</td><td>Cleveland V8</td><td>1971-1974</td><td style="text-align: left;">400, 78.4cc chambers, 2.04/1.66 valves, same config as early 2V head</td></tr></tbody></table>

 

It all depends on your compression ratio and cam timing. The standard heads do cause detonation or run-on with very much compression and a torque cam. Which is one reason Ford dropped the CR on these engines.

So, you have to determine your target CR and cam before worrying about heads. In any event, call Tim, tell him what you want to do, follow his guidance, and buy your parts from him.

 

My 400 in my 1977 truck was rebuilt with stock internals and stock replacement pistons with open chamber stock 2V heads, I live at 5500-6000 ft and I HAVE to use 91 during the hot summer and 89 during winter to avoid pinging, I can barely get away with 87 octane fuel if its freezing and I retard my timing AND avoid every hill in the Sierra Nevada Mountain range (which is effing impossible).... Yes, the open chamber heads suck and obviously ping like a ****, or maybe it's just I got the one engine that is unhappy lol Doubt it though... I hate hearing those little gremlins hammering inside my engine so I usually stick to 91 and call it good.
Now I am building a new 400 with closed chamber heads and a 13cc dished piston sitting .005' above deck, I should'nt have anymore ping, for good quench we have to keep quench right around .040" for best results I have been told.

 

don't really have a target, just don't want detonation, with the 78 cc heads and maybe a deh 255 or deh 265 comp cam and t/meyer kb 400 pistons it should be under 9.5