I've done some other research but the GRM community knows so much about so much that I thought I'd ask the question here. I've always wanted to manual swap Elmore, my '67 F350. From what I can figure, finding a big block, 2WD ZF5 seems to be the most straight forward swap.
The engine in my truck is a 429 out of a '71 Thunderbird. I have found an S-42, big block, 2WD trans semi-locally for what seems to be an OK price and am trying to price out the rest of the swap. I know the S-47 is considered the "better" ZF5 for this application but that seems to be primarily because it is rated for 50 lb/ft more torque. Either one is rated for plenty for my application.
My truck had a manual trans from the factory and the old clutch pedal is still hanging there. It seems like I need flywheel, clutch, pressure plate, slave, master, line and will almost certainly have to have the front driveshaft lengthened.
Is there anything I need to be aware of in regards to flywheel/engine balancing? The trans is said to be out of an '87 F250.
You will need an internal balance flywheel, all 429s are internal balance and 460s went external balance in the late 70s.
Not sure what this will do for clutch shenanigans though.
I put a ZF5 S-42 5 speed behind the 351W in my '71 Bronco. I'm aware of the different cases for the 2wd and 4wd versions (mainly tailshaft differences), and the diesel version with the much larger bellhousing, but I'm not aware of a "big block" version of the ZF. Does it have a bellhousing that fits the big block bolt pattern?
As far as flywheel/clutch/etc, I used a stock 351W flywheel and clutch, the spline count and diameter of the clutch disc mated with the input shaft of the ZF just fine - because they were available from Ford from the factory.
You should be able to use your stock flywheel, and a clutch disk/pressure plate package that will fit both your flywheel and trans input shaft.
In reply to Pete. (l33t FS) :
OK, thanks.
In reply to earlybroncoguy1 :
Yes, it's my understanding that the small blocks and big blocks have a different bolt pattern for the bell housing. I feel like that would be the case for me in regards to the clutch/pressure plate. I would think if I get the correct flywheel for the engine and the clutch kit for the truck the transmission came out of that would all be kosher.
In reply to earlybroncoguy1 :
The early '90s Ford i have came with a 460FI / ZF 5 speed, and now has an early'80s carbed 460.
Very different stuff than the Windsor. 429 is same bolt pattern as 460, but with the different flywheel , not sure how that would affect the clutch stuff. At a guess, i would think a 429 flywheel, and clutch "finger plate" (drawing a blank on name!) with a '90s 460 clutch friction plate would do it. Make sure pilot bushing is correct, also.
Keep in mind, I'm strictly bench racing here, but I know the Windsor stuff ain't it.
I have continued to research and it seems that the later clutches don't jive with the early neutral-balance flywheels. It seems the path forward is to buy an external balanced flywheel, make it neutral balance and use the later clutch.
A couple posts from other forums posted so I can find again:
mckst - ford-trucks.com
I am doing a very similar swap. I have a '71 429 with a 1990 ZF 5-speed. Ford changed from a internal balance to an external balance big block midway through the '77 model year. This means that the later model flywheel is NOT "neutral balance" like the earlier models. Somewhere along the line, Ford also changed from a 3 finger clutch set-up(6 pressure plate to flywheel bolts) to a 4 finger set-up(8 bolts). So what you need is a neutral balance flywheel with the later model 4 finger clutch/pressure plate bolt pattern. You have a few options: you can use the early model flywheel(make sure it has the same O.D.) and have it drilled/balanced to accept the newer clutch/pressure plate assembly, or you can do what I did and buy a later model flywheel, have the weight eccentric machined off and put a neutral balance on it. Other options include balancing the flywheel with the crankshaft(or even better the entire rotating/reciprocating assembly) or looking into compatability of the older 3 finger clutches with the zf input shaft.
averagef250 - fordification.com
The flywheel/clutch is a bit of an issue. the early 429/460's were internal balance and used a small flywheel and clutch (different pressure plate bolt pattern). The later 460's with the ZF 5 speeds were external balance with a larger flywheel/12.25" clutch. The flywheels bolt in place of one another, but the balance is wrong.
If I was doing it I would mill the later flywheel to be internal balance and have it balanced on a crankshaft balancer.
Another thing I'll need is a starter.
- Trans
- Flywheel - for a later 460 truck, zero'd out
- Clutch kit - for a later 460 truck
- Starter - again, for a later 460 truck
- Master & slave for later truck
- Fabricate a crossmember
- Fab clutch lines
Noddaz
PowerDork
4/24/24 12:59 p.m.
And reinforce the firewall area where the clutch master is bolted to.
In reply to AxeHealey :
In my search for 351w flywheels I remember some having the weight as bolt on. I'll see what I can find for a 429/460.
EDIT Well that didn't take long.
https://www.summitracing.com/search/part-type/flywheels/make/ford/engine-size/7-5l-460/engine-family/ford-big-block-385-series?N=engine-balance%3Ainternal&SortBy=Default&SortOrder=Ascending&keyword=flywheel&kr=flywheel
No wait those are 6 bolt. Let me look more.
No it seems some of those might work. Some look like 6 bolts for the flywheel but others look like 8 bolts.
In reply to Stampie :
Oh, nice! Thank you.
I guess I shouldn't be surprised that there's an off the shelf option. I *think* I'll want a 176 tooth ring gear for the later starter...
