Here's the deal..

89' F-150, I'm currently running a 91' 351 efi motor, with a NP435 behind it, aluminum bellhousing, hydro clutch.

I'm putting in a 460 from a 89' F-350. Motor originally had a ZF behind it, 12 1/4" clutch, 1 1/4 input shaft.

I was test fitting it all tonight, and ran into some issues..

89' 460, stock ZF flywheel, re drilled for a 12" clutch
Clutch is for a 400, 12" 3 finger pressure plate.
bellhousing is an older cast iron unit, from a 400 4 speed truck.
tranny is a NP435.

I have the motor hanging from the crane right now, and tried test fitting the bellhousing, so I can build a bracket to mount the slave to. the bellhousing cranks down hard the last 1/2" or so, and at about that point, the clutch fork and throwout bearing bottom out in the back of the bellhousing, and the clutch begins to release.

I came across this thread, http://www.pirate4x4.com/forum/showthread.php?t=461230&highlight=460+bellhousing which mentions the bellhousings being 1/2 deeper, but it doesn't seem like it would relate to my situation..

Only thing i can figure, is the externally balanced flywheel is 1/2" thicker??
any suggestions?

The 400 bellhousing isn't going to clear your flywheel, as you've already learned. The external balance 460 flywheel is larger in diameter and deeper. It doesn't work in a 400 bell like a smaller internal balance one does.
I have read of guys just clearancing the inside of the bellhousing, but, I don't see that helping your clutch issue, that may just be the long style clutch instead of a diaphragm.
I really suggest finding a 460/4 speed bell, and while you're at it, grab the 460/diesel style clutch hydraulics(ZF stuff works too,) and you won't have to fabricate anything.
I'd offer you my spare, but, I won't be able to get near the truck it's in for another good month.

yeah, the hydro bell would be the way to go, but that also makes me wonder what it would do to the input on the tranny, being a 1/2" to short..

L&L makes a flywheel to make it work... which makes me wonder what the difference is in it between mine... I'll machine off 1/2" if thats all their flywheels are..

IMHO I would not machine .500 off the flywheel.

Yeah, I'd rather not too, but that makes me really wonder whats different on a L&L flywheel, that allows a M bellhousing to work on an 80's motor..

Yeah, I'd rather not too, but that makes me really wonder whats different on a L&L flywheel, that allows a M bellhousing to work on an 80's motor..

Well, do you think that maybe it is SMALLER, but is made with the 460 crank flange pattern. :rolleyes: Don't really know, but what else could it be. ;)

I also here 360/390 flywheels work for this purpose as they are same size as 400, but with 460 crank pattern, but they may be getting rare or obsolete. I wouldn't be surprised if the L/L wasn't just a reproduction of them.

no, the 360/390 flywheels are zero balance, they work fine for the 78 and older 460's, but not on the newr 460's, which are externaly balanced.

Smaller in what way? the diameter can't be smaller, or the starter wouldn't engage, even still the diameter wouldn't matter.
The only difference I can really picture is, the flywheel is thinner..

no, the 360/390 flywheels are zero balance, they work fine for the 78 and older 460's, but not on the newr 460's, which are externaly balanced.

Smaller in what way? the diameter can't be smaller, or the starter wouldn't engage, even still the diameter wouldn't matter.
The only difference I can really picture is, the flywheel is thinner..

Yeah I was thinking the older 460's. I didn't know where the cut-off was. I didn't think it was that far back. Not looking at it, I would have to say the crank flange must be farther out from the mounting face for the bell. The flywheel has to be thick for heat absorption. As far as the starter goes, as long as the bell and flywheel are matched to each other(the proper distance from each other), and the tooth pitch is the same, the starter wouldn't be a problem.

I can't imagine a flywheel that could stand to have 1/2" machined away, but if you are looking at the 2 side by side and that is the ONLY difference, maybe that's what it needs. I doubt its a weaker material, and needs to be thicker.

The flywheels both use the same 180 tooth ring gear, so, diameter isn't the issue.
It must be that the crank flange is further out, and the ring gear sits the same distance back towards the engine to compensate.

If you machine a 1/2" off the flywheel then you will just have a flexplate.:flipoff2:

yeah, I pulled it all apart today, and it looks like the crank sticks out further on a 79+ motor..

Which makes me wonder... what does a 79' 460 truck use for a bellhousing?

Im goin to be doin the same awap into a 78 my buddy done it a couple times he says the sleeve on the tranny shaft u take off and cut 1/2 off of it thus makin the clutch not engage

sleeve on the tranny shaft? I'm not sure what you mean there? I assume he always used 70's motors though?

What does a 79 truck use for a bellhousing? Easy answer, different spacing on the flexplate for the C6.... The 460 was never offered with a manual trans before 83.

hmm, really, I was thinking that 2wd trucks could be had with a 460... i guess that would make sense though..

The 460 was 2wd/auto only up until 79, wasn't offered 80-82, and 83 was the first year it came in a 4x4 or with a stick. Which is why L&L can charge exorbant amounts for their stuff and get away with it.

hmm..

well, I made it work today..

i made a bellhousing spacer out of 1/2" plate, and incorperated the slave mount into that..

I also realized the piloit bushing sticks out way to far.. but after knocking it out, and knocking the one out of my windsor, I found it drops right into the 460 crank.

Either way, the motor is in the truck, and bolted to the tranny. Looks like the I should be able to make the 460 mounts in the 351 towers..
That, and rewiring the chassis harness to work with a remote TFI, and I should be golden.

too bad ur in MI I Got A 460 Outta A 88 F350 Got The Engine Harness And Throttle Body And Intake Etc. Been Tryin To Get Rid Of It

I'm interested in doing a similar swap. np435/205 behind 1997 460 in an f350.
Question? Can i use the 97 dual pattern flywheel? Will it be drilled for a 12 in clutch. I have to order a flywheel anyway so I dont mind getting what I need. If I use a 12in diaphram clutch and a 70's 400 bell/fork/ bearing on the 97 flywheel and trim the 1/4 to 1/2 inch off the end of the bearing retainer should I clear.. Any help guys would be great. I did search but most of the info I can find relates to swapping a 460 into a 70s ford. I plan on using an external slave and builting a bracket to mount it with the z bar style fork.
Anyone who has a better suggestion please speak up. I know I could go ZF5 and it would be easy but I have a several complete 435/205 setups already. Also have the 400 bellhousing.

Hi,
I'm new to this page and am going thru the same thing as you, except mine is an older model 460, internal balanced. I'm using a 390 flywheel because it's neutral bal. and same diameter as a 460. Same number of teeth.
Also I checked the starter drives and they are the same for both, teeth and pitch.
Now I've run into a problem with the pilot bushing/ bearing. I checked the 460 bearing and a small block type. They are the same except the 460 has an extra step up on the outer side. The extra length may hit the input shaft at the teeth. Compare them and see, but I hope the Small block one works.
About your issue with the clutch being depressed as you tighten the bellhousing down, sounds like maybe the wrong Throw Out Bearing. The original one in my 390 truck compared to the 460 one is shorter than the other. I'd use the shorter. Also the Release Forks have two (that I know of) mounting types. The first is the old Ford Standard Stamped steel, and the other is a aluminum block that only sticks up about 1/2"/ compared to the others 3/4"+.
I haven't tried them yet but will soon. The shorter Throw Out and the Shorter Fork pivot may fix the clutch release problem.
I hope this helps, I will follow up on this as I proceed.
Ray