G50 not flipped.

A little bit of engineering that I did on the first GTD 40 build about ten years ago
We were throwing ideas about regarding transaxles for the 40 and decided to go for the G50. I did not like the look of the adapter plates and was not happy with running it upside down because of the driveshaft angles. I made a split mold and had cast a housing that would allow the diff to be installed on the other side of the pinion, the same mold was made to take a separate bellhousing which in turn could then take a normal ford flywheel + full size clutch with the starter in the normal place. The Casting was made 30mm plus thick so that all the ribbing could be machined on the outside afterwards . it seems like a lot of work but to cast the ribbing on this type of mold would have been a lot more work. The casting was also machined to take the original G50 side cover. With all the machining done you can barely tell it apart from a factory job. Also runs dead straight driveshafts as installed.




The flange of the diff housing was machined to take the same bolt pattern as the pantera zf unit. Below is the mold made for the bellhousing which is just a filled and painted pantera unit.



The clutch drive plate was from a 928 porsche and the release bearing was a mcleod hydraulic just to keep it simple. I will get some pictures of it in the car in its finished guise with all the ribs machined on. Its been in the car ten years now with now problems. Only the one was cast because a zf turned up for the second build but without that I would be doing another one.

Bob

Edit .G50 diff housing up for grabs if anyone needs it.
 
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Bob:
Thats some piece of work, this is the stuff I really like to see, and as you said you didn't like the look of the adapter plate, and I agree as it always looks exactly like its description because it always has that appearance of something of a go between part.
I am thinking this is what led you to go to this setup.
I have a couple of questions if its OK..
How long did the whole setup end up being in the chassis?
Were you able to cover the area below the crank centerline in front of the flywheel...were you able to use a stock Ford setup like the stamped cover thats available?
Can you duplicate this part because I think the idea is way better than an adapter.
Last but not least can we have some photos of that whole setup?

Cheers
Phil
 
Bob:
Something of an afterthought...would it be possible to add lugs to the top of your casting and hang the gearbox from the crossmember similar to a ZF mounting.
Cheers
Phil
 
Chris that must have been a programmers nightmare :)

Bob:
Something of an afterthought...would it be possible to add lugs to the top of your casting and hang the gearbox from the crossmember similar to a ZF mounting.
Cheers
Phil
Thats what we did Phil. The first mold you see is the wooden buck below is the buck cast in ali with the mounting lugs fitted. This became the mold proper if you like. These worked out really well because there are very few other places to mount the G50. It also left the back of the box clear for just the gear change. Will post that up another day.



We also had some billet heavy duty side covers made.


And here is a picture of the case as machined with the bell housing.



The above is the only picture I have of this. the one in the car is buried, It is basically just two bits, the diff housing which is a one piece casting and the bellhousing, The standard ford cover plate fitted this so there was no need to fill in the underside. The transition between the bellhousing and the diff housing had to done on the mill because of the casting technique`s

The release bearing sat nicely in the pocket.



Sorry about the lack of details boys but I am not good with a computer or a camera but I have just mastered photobucket :)
Bob

Edit. I have stuck this in the wrong section, sorry chaps:embarassed:
 
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Incredible job!!!!! are you going to mass produce these or one offs, I see a market, keep up the good work, Neville Nesbitt.
 

Randy V

Admin
Lifetime Supporter
Very nice job!!!!

So pardon my ignorance but will this allow the crown gear and differential from something like the 930 box to be used with the G50?
I have a G50/03 for my car and my only real concern is the strength of the differential..
 
Very nice job!!!!

So pardon my ignorance but will this allow the crown gear and differential from something like the 930 box to be used with the G50?
I have a G50/03 for my car and my only real concern is the strength of the differential..
Randy the G50 is a tough little lot, the side cover of the diff housing is apparently a weak point which is a very easy fix . But on that note the first 40 we built made just over 500hp in the rollers and that has not killed a bone stock G50 in ten years of very heavy abuse.The only driveline failure we had was an exploded cv joint. I dont think a sbf could eat a g50 :)

Bob
 

Randy V

Admin
Lifetime Supporter
Hi Bob.. Thanks for the words of encouragement.
I have a PatrickMotorsports sidecover for mine that will be installed.. As I understood it, there were two different G50 housings, one of them was for the 5spd turbo porsche which had a bigger differential and ring(crown) gear.. Mine is not the turbo unit..
 
Sorry the pictures got wiped out when I had a tidy up in photobucket .

the original concept.



The mold proper.



The bellhousing mold.



The finished prototype.



The heavy duty side cover.


Inside the bellhousing.



This project has been put to sleep for the last 10 years but due to the response I have had I think I will go back to it and re engineer a few bits to make it more adaptable to other engines. I will also re cast the center section (two side covers) to enable the casting to be used flipped or conventional, the reason for this is if a taller engine was used say a 351w and it was drysumped to lower it in the chassis it would not need flipping to get the driveshaft angle right. I will reconfigure the bellhousing to gearbox bolt pattern to be eight bolt equally spaced, that will allow the bellhousing to be used either way round. Lastly I will make a few different bellhousings to go with the other v8`s commonly being used like the ls,bmw etc. This will take a few months so I will keep you all updated. If it turns out well I will market them but as we speak its just development work:)

Bob
 
HI BOB,I AM FINISHING A ULTIMA SPYDER WITH A G50.BUT THE FRONT CASING(WHERE THE GEAR CHANGE MECHANISM COMES OUT)IS MISSING.WONDERING IF YOU CAN SELL THIS PART TO ME?:idea:
 
Still work in progress on this but it wont be long now, The mods include the hole for the speed transducer and the bolt pattern on the bellhousings being symmetric which will allow 180 degree rotation. The original is still in the car and is in its eleventh year with no issues so I am happy enough with original design in terms of strength. I will also add a mounting boss on the bottom of the bellhousings as per original 40`s for added stability.

Bob

 
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