Inverting/Flipping a ZF

Hi,

I have tried to gather information about the procedure for inverting the ZF (from Pantera to GT40 orientation). After spending quite some time on various forums, I still think I lack a conclusive answer. Sometimes this 180 deg. flip seems to require the act of a wizard, whereas others just invert the diff/ring gear and drill/block holes for communication, filling and draining. I would greatly appreciate if you guys could help me gaining confidence for performing this trick on my own… Hence, I would like to be sure what the crucial steps are.

Thank you in advance,
Mattias
PS. I have read the “free ERA build manual” and from that it seems straight forward.
 
Mattias:
I have done 2 boxes and both are still working well.
The holes in the bottom of the case are pretty straight forward, and the mods to the case are generally just a couple of threaded holes, although I did weld a bung in the area where the drain now is, and threaded that. The carrier is a little more involved.
The two things you will need to take care with are removing the carrier bearings (must be done to remove the carrier assy.), the carrier must then be re-set as far as bearing pre-load and backlash at the pinion. Take the main case and clean it throughly after the work.
Replace any bearings that you think may be even marginal while the box is apart, and it is always nice to have a gasket kit before you start.
The thin gaskets on the side covers are used to set the carrier, and you may want to be sure to have them along with a couple of hub seals.
You can buy or download a service manual that will guide you, and you may want to get some advice on what to look for as far as wear points.
There was a posting some time ago on the forum of a bearing puller for the carrier bearing if you do a search.
Get a good bench to do the work, and space to lay out everything. These boxes are quite heavy so use caution also when doing the work so as not to bang up the case.
Good luck
Cheers
Phil
 
Why does a ZF set up for a Pantera need to be flipped for a GT40? I thought they're both the same drive configuration (engine ahead of the drive axles)??
 
The Driveshaft on the Pantera is above the centerline of the axle/differential.

The engine in GT40s sits lower, and has the driveshaft/input shaft below the centerline of the axle/diff.
 
-Thank you Phil. This was precisely what I was looking for, superb firsthand information from someone who has performed this himself and obviously succeeded. Regarding the puller, I remember seeing a device consisting of two “half-circles” that clamps around the bearing when being bolted to a cylinder… (can’t find it again though). May I ask what type of sealant I should use? The manual I have read just mentions “non-hardening aircraft spec”.

Thanks,
Mattias
 
I can't believe I forgot to mention the sealer, I will post the exact product this morning when I get to the shop.
Also, you are correct about the puller. it looks similar to the puller for a power steering pulley, except that I think it was more than two halves...I have that drawing somewhere and it would be no problem getting that to you, I am sure it is on the forum somewhere also.
Cheers
Phil
 

Ron McCall

Supporter
Hi,

I have tried to gather information about the procedure for inverting the ZF (from Pantera to GT40 orientation). After spending quite some time on various forums, I still think I lack a conclusive answer. Sometimes this 180 deg. flip seems to require the act of a wizard, whereas others just invert the diff/ring gear and drill/block holes for communication, filling and draining. I would greatly appreciate if you guys could help me gaining confidence for performing this trick on my own… Hence, I would like to be sure what the crucial steps are.

Thank you in advance,
Mattias
PS. I have read the “free ERA build manual” and from that it seems straight forward.

PM sent

Ron
 
Mattias:
The sealant we used was Hylomar PL-32, It is a non hardening sealant used in the aerospace industries, impervious to most fuels, solvents and oils.
Check it out here: Welcome to Hylomar
Good luck with your project and let me know if you need the drawing for that bearing puller.
Phil
 

Randy V

Moderator-Admin
Staff member
Admin
Lifetime Supporter
Wear your rubber gloves when working with hylomar as it seems it is also impervious to SOAP!

:eek:
 
I spent two days with Lloyd Butfoy when he converted my spare Pantera ZF gearbox for eventual Superformance GT40 use (I've got a gearbox, now all I need is $120,000 and I can get the rest of the car!).

I shot about 200 photos of the process, which was long and involved. True, the photography slowed it down, but it still would require about 10-12 hours work under normal circumstances, including a full rebuild. There were numerous components that still had some minimal service life left, but were close to the end (think of a set of tires that is nearly bald, but the cord isn't showing yet!) so those were replaced as part of the process. The problem for a do-it-yourselfer is that you won't know what parts you need until you get it apart, and if you don't have specific experience with these gearboxes, you might not be able to recognize components that really should be replaced.

(I sure couldn't tell that some of the various components in my gearbox were bad, until he showed me and contrasted them with similar pieces that were either new, or serviceable).

If you have the ZF overhaul manual (available from any of the Pantera parts vendors), that will tell you what you need to know to dismantle and reassemble the gearbox. The ERA manual has the specifics you need for converting it to GT40/Mangusta orientation.

And if, after you have blown it all apart, you find that you are in over your head, I urge you to crate it up and send it to Paul Fleming in the UK. He's Europe's leading specialist in these things, and he's used to getting gearboxes in bits that others have tried to overhaul, but wisely gave up on. In fact, just last week I arranged for a friend from Finland whose gearbox was in pieces in Sweden, to have it sent to Paul; he's going to do the job right, and for substantially less than the Swedish 'expert' (who had never seen one of these gearboxes) was planning to charge.

Here's Paul's contact info:

Paul Fleming
Maldon, Essex
England

e-mail: [email protected]

mobile: 07710 778672
Tel/Fax: editted at request of user

Even if you tackle the rebuild yourself, you're likely to need parts (perhaps a LOT of parts), and he's probably the best source for them in Europe, so you'll want to be calling him anyway.

Good luck, whichever path you choose to take! :thumbsup:

Oh, and Cliff--if you bolt a Pantera gearbox up in GT40 orientation without first doing the aforementioned modification, you will have a car with one forward speed and five in reverse! :laugh:
 
Last edited by a moderator:
"reads with interest" I am doing the opposite, converting an M1, ZF box to Pantera configuration.

I believe the input shaft is too long to allow an M1 gearbox to work in a Pantera. Talk to Paul Donderwinkel down there; he's the local ZF guru for New Zealand. PM me for contact info for him.

BTW are you a Pantera guy?
 
Phil, Ron, Randy and Mike,

Thanks a lot for all your help. This forum is truly excellent.
Despite your “warnings” Mike I think I have gained enough confidence to make an attempt at performing this operation. I have reasonably good experience from working with ZF’s (non-transaxle) and rear axles for 60:s-70:s Alfa Romeos. Hence, I’m not in general afraid of messing with gearboxes, on the other hand I’m not filthy rich either and would like to avoid the most obvious expensive mistakes.

/Mattias
 

Rick Muck- Mark IV

GT40s Sponsor
Supporter
I believe the input shaft is too long to allow an M1 gearbox to work in a Pantera.

Yes,

The M1 box shaft is several thou too long for a Ford...ask me how I know! When P1116 was assembled we didn't know that and wiped the thrust bearings out of the engine in 10 miles. You must shorten the input shaft or suffer the results!
 
I believe the input shaft is too long to allow an M1 gearbox to work in a Pantera. Talk to Paul Donderwinkel down there; he's the local ZF guru for New Zealand. PM me for contact info for him.

BTW are you a Pantera guy?

Its not going in a Pantera, its going in an all aluminium replica of a BMW M1, with a Chevy on the front. Special bellhousing cast to do the deed as it were. I'll check the length though with the bellhousing etc and see how it looks.
 

Jack Houpe

GT40s Supporter
Yes,

The M1 box shaft is several thou too long for a Ford...ask me how I know! When P1116 was assembled we didn't know that and wiped the thrust bearings out of the engine in 10 miles. You must shorten the input shaft or suffer the results!

I run the M1 in my SPF, the only problem I had was switching the shift lever from left to right. Length of the shaft was not a problem but I had to mill a bronze bushing for metric ID and standard OD. Also the splines are different! Remember that when ordering a clutch.
 
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