I was wondering what fly wheel/ clutch would be needed to swap a 400 out of a 78 f150 into my 85 its got a 351w in it now, also is it possible to adapt a mechanical clutch bell housing into a hydraulic clutch bell housing the motors coming out of a automatic tranny truck so im gonna have to source the clutch, fly wheel and maybe mechanical clutch linkage if I cant adapt my bbf bellhousing to hydraulic clutch.. just brain storming here any info would be appreciated

 

Your bell will NOT fit a 351M/400 engine.
Auto does not have a bellhousing.

 

Bulldog - I would like to help but can't get my head around what you typed. I tried to read it twice but got lost and gave up. Sorry.

 

Sorry for my bad typing earlier, I think I had to much coffee.
Anyways I have a 78 f150 and its got a 400 in it and a c6 tranny, I also have a big block bellhousing but its set up for a mechanical clutch, I was wondering if I could convert the mechanical bellhousing into a hydraulic clutch by attaching a slave cylinder some how, and then I was wondering what size flywheel would be needed and what size clutch also. once again sorry for the confusion I hope this clears it up.. Also you can call me matt

 

So; you wanting to put a 400 that had an automatic transmission into another truck, but use the manual transmission from the truck you are moving it to?

 

Matt - That helped me understand the previous post, but raised questions like KSC asked. We need to understand more of what you are trying to do in order to properly answer. However, you asked two questions:

1. Hydraulic linkage: It is certainly possible to attach a slave cylinder, but the "somehow" is the million dollar question. I'd be planning to find a hydraulic bell housing instead, and I like to do things myself.
2. Flywheel: The flywheels are all the same size for the 400's, but the clutch size varies by application with both 11" and 12" available. And some flywheels were drilled for both clutch sizes.

Having said all that, since you mentioned "big block bell housing" you need to know that the M/400's have the flywheel ~1/2" further forward than a 460 does. So, while the 460's bell housing bolts up just fine the input shaft on the tranny comes up short of reasonable engagement in the pilot bearing. IOW, you can bolt a 460's bell housing and tranny to a 351M or 400 but it is not going to work.

Or, you can use a 351M/400 bell housing and the tranny will be fine. Unless you are talking about a tranny with an integral bell housing, like the ZF5, in which case you have to have some modifications.

 

From what I remember back in the day after the 351C was morphed into the 351M and then later into the 400M those motors were not desirable at all. Why would you want to use a 400M over a 351W? You could easily (and cheaply) mod the 351W a bit to find the power that you are looking for. 351W parts are plentiful on the after market scene while the 351M parts are kind of few and far between. Especially performance parts.

If you were swapping an early 70's 351C maybe I could see it but in my book a 351M/400M is nothing more than an underpowered smog boat anchor. JMHO from the way I remember things and I have been a tried and true Ford guy since I was 16.

 

I beg to differ. First, lets set the history straight as it makes a difference: the 400 came before the 351M. Read Bubba's site if you don't believe me.

Second, while you are right that 351W parts abound, there are parts for the 400 - although not so much for the M. And if you don't believe me read Tim Meyer's site. The critical thing is pistons, and Tim is supplying those for the 400. And others are jumping on the bandwagon rapidly. Just go look at the engine of choice for many going to the Engine Masters competition - the 400 is frequently used. Why? The 4" stock stroke is the longest in any Ford V8, ever. Stroke gives mechanical advantage with begats torque. How much? Many, including Tim Meyer and my machine shop as well as Comp Cams Cam Quest desktop dyno, say my build will easily give 500+ ft-lbs at about 2500 RPM.

I will grant that I'm using aluminum heads and a roller cam, but even stock heads with Tim's pistons will give over 400 ft-lbs. And, the heads flow far better than 351W heads. Why? They were designed for the 400 and then adapted to the 351M while the 351W's heads were originally designed for a 260 and adapted up through a 289 and 302 to a 351W. Basically, the ports in a 400's head dwarf those in a 351W head.

 

Thank you for the info on the bellhouse, it came off a np435 that was bolted to a 460 so I guess that's a no go, and I was wondering about the clutch sizes and you cleared that up to, im wanting to go to the 400 because the it had a complete top end rebuild and some head work done plus theres no replacement for displacement .

 

You just need to find the right bell housing. The NP435 was used behind the 400 so the bell housings are out there. In fact, that and the C6 were two of the most popular transmissions behind that engine.

Attached is a page from the master parts catalog showing the bell housings - which were called "housing (clutch)" by Ford. I'm confident there's a significant mistake on this page since it says "351, 400", which includes the 351W. But since the W series took a totally different bell housing that is obviously wrong. In any event you can see that the 351M/400 takes one bell housing and the 460/7.5L takes a different one.

 

No need getting testy about it. I am just stating my opinion (which I clearly said above) from what I remember from days ago. If the 400M came out before the 351M well then that's fine and dandy. I just remember none of my mechanic friends liking them very much. I respect your opinion on the matter as well I hope you respect mine. This isn't a pissing contest.

 

Back to the original idea. A '78 400 into an '85 in place of a 351W.

Is the 400 stock, and if so, how many miles? IMO it makes no sense to swap in a worn out motor in this case with all the changes required to make it work. Lots of time and effort and money towards just making it fit.

I'd fix the 351W. It's fairly easy to outpower a 400 with a few mods.

If the 400 is fresh or mod'd, it might make more sense.

And another thing--is the '78 such a steaming pile that it deserves to be stripped and deactivated, or is it a runner?
JMO....

 

Sorry. Didn't meant to be testy. But I probably agree with your mechanic friends - stock 351M's were dogs. Most had 8.0:1 compression ratio and retarded cams such that they couldn't get out of their own way. 400's (Ford never called it a 400M as there was only one 400) had 8.4:1 CR and the same retarded cam.

But that was stock. All it takes is a cam and timing set change and these engines come alive. Until I pulled Dad's down for this build I had two M's running at the same time. Step on the throttle for Dad's and little happened save for the fuel gauge dropping. Step on the gas for Rusty and it jumps - and uses far less fuel doing it. Why? A simple RV cam and timing set change. Everything else that is needed, like large ports and valves that W owners would kill for, are already there.

 

I can't make it out from the chart, but the question is did they make a 351m/400 bellhousing with a hydraulic clutch setup? I know the early setups where mechanical, and then the 351m/400 got discontinued. Did they quit using those engines before they went to the hydraulic clutch? If they did have one, it would not be but a year or so in use would it? If that's so, it may be hard to find.

The 460 bellhousing situation. Gary, you said it was too deep? Are there any options to make it work? Has anyone made or does someone make a extended pilot bearing to mate up with the tranny shaft? The 460 hydraulic clutch bell would be a lot easier to find.

 

Dave - Good questions. I'll research the hydraulic linkage bit, but I'll put money on that the M/400 went away at the same time hydraulics came in. And, if there was any theoretical overlap I'm sure they are an exception as it wouldn't make sense to outfit them with a slave cylinder.

On the pilot bearing, I simplified the issue since I didn't think anyone would go down that road. But, if you use a 460 bell you have exactly the same problem I had with the ZF - essentially no pilot bearing engagement and very poor spline engagement. So you should use my spacer, move the ring gear forward on the flywheel, and use a 351W automatic starter. I'd go to a manual clutch linkage LONG before doing that.