Real GT40 Bellhousing dimension

[Brian Coombs]

I wonder if anyone can help me? I am trying to find out what the width of a original MK1 GT40 bellhousing is, from block face to gearbox mounting face?

Thanks.

Brian Coombs

 

[John Fitzpatrick]

Brian-
Ive got one and I'll measure it for you tonight. Any other measurements you need while I'm at it?
You can see the bell housing I've got here: http://www.gt40s.com/forum/gt40-tech-powertrain-transaxles/34176-help-iding-bellhousing.html

What's it's final destination?

 

[John Fitzpatrick]

Brian,​

The front to back overall bellhousing dimension is a nominal 4.00 inches. The engine side of the bellhousing is flush, the transaxle is aligned against the bell housing by a 0.125” x 0.125”ring machined into its face which matches a circular step on the transaxle, so allow for that in your overall measurement. Also, because the bell housing only encircles the back of the flywheel which protrudes below the oil pan, you'll need the plate that goes between the transaxle face and the engine, protecting the front of the flywheel. They're still available, and the one I got was stamped from 16 gauge steel, but the die they used left a lot of flash and it wasn’t an exact match to the ZF, so I ended up using it as a template to trace the inside cut-outs and the bellhousing for the outside. I’ll get it water jet cut later when I do my turkey pan base. If the one you use isn't smooth and flat, your alignment can be thrown off which can cause all sorts of problems. I think Jay Cushman sells a proper one. Just allow for an extra 1/16th” because it affects your motor mount to axle distance.

John
​

 

[Brian Coombs]

Thanks John.

I thought that was the case. The Bellhousing drawing I have is 4"
I have been modeling a replica chassis on CAD, and I have various drawings of chassis panels that don't tally and I was wondering which was correct!

 

[John Fitzpatrick]

Brian-
Which CAD? I've used AutoCAD and Rhino 3D. I think Rhino is more intuitive and just as accurate as AC but the instructions are crap unless you're doing mostly compound curved surfaces like a body shell.
And greatings from a 3rd generation ex-pat from County Cork!

 

[Brian Coombs]

Thanks John,

As a mechanical design engineer I use a a CAD package made by Siemens called NX (I think we are currently using NX7) it is good at solid modeling and surfacing, but they are always updating it and moving the buttons so you can't find the command you want! it can translate most other CAD formats DXF STEP IGES Parasolid etc.

Where about's in Cork were your family from? I live on the Beara peninsular, near Kenmare.

 

[John Fitzpatrick]

Brian –​

I was back in the Auld sod in 1969, but I just remember my grandmother saying County Cork was where grandfather’s parents were buried. She came over on the boat herself from England about the same time he arrived from Ireland, and evidently when she announced she was marrying a heathen Irish-Catholic trolley conductor (her father had been one of Queen Victoria's royal draftsman), there was considerable weeping and wailing and gnashing of teeth amongst the Protestants of the Wheatley family.​

I guess engineering runs in the family –great-grandfather Wheatley became a machinist once he got here and family legend says invented the roller window shade, grandfather Fitzpatrick (the heathen Irishman) invented the clasped-hand style train car coupling that replaced the crossed chain and bumper method, although he never made any money from it, and my father was a registered professional engineer. Thank God my son was a theater major!


Crap, none of this has anything to do with bellhousings, and I apologize for tracking mud across your thread. Shoot me an e-mail and tell me something about NX-7 -- do you know if it's anything like Swiss program VisionAEL?
​