I'm just going to throw this out as food for thought.
From my reading on the forum, the availability of 2nd hand G50s isn't what it used to be. I would imagine the current crop of suitable Audi boxes will begin to dry up eventually, too.
There are also people out there who (I assume) would like a new transaxle for their GT40 / Lola / Ultima etc, but price is a major barrier.
In Australia, a new Porsche gearbox is around $18-$23K depending on model. I imagine a new ZF or RBT-6 is somewhere in that ball park. Mendola is at the lower end of this range, but unproven in an application of the kind we are interested in AFAIK. I don't know the cost of the new Xtrac transverse transaxle.
There is a lot of amazing engineering experience on the forum. So, why hasn't someone designed, built and profitably produced a strong 5 or 6 speed transaxle with decent gearing for under US$10K?
Don't shoot me down just yet - listen to my idea. You've may have even thought of it yourself...
Build a prototype based on 2nd hand Tremec or Richardson etc. Make a longer input shaft. Or, even better, make an input shaft extension. Then put a hole in the front of the gearbox and attach an extension for the output shaft (that goes on to the front rather than the rear of the shaft) with a gear on the end. Set an equally strong ATB diff between the 2 shafts (or above the output) with a gear on its input. The diff sits the correct way round and is driven from the gearbox output shaft extension via a reversing gear, so everything spins in the right direction.
I'm sure you can see where I'm going with this. I never said there wouldn't be a lot of machining involved!
Make a frame to support all of this and to take a bellhousing at the very front, over the input shaft extension. Once all the mounting points are properly located relative to each other, have a think about the stresses involved, and use your CAD experience to knock up a case design that mounts between the bellhousing and the gearbox, and that carries (and oils) the diff, and locates and seals all the shafts etc.
You can now produce new transaxles using commercially mass produced bellhousings, gearboxes and diffs, with you supplying CNC'd input and output shaft extensions and the intermediate case, and machining any necessary parts of the gearbox. You could go the whole hog and do a completely new case, but I think that would merely cut into profitability.
Oh, and you might want to consider a business plan before doing any of the above! I'm making assumptions about the costings, but would imagine a unit using new parts would cost less than US$6,000 if much of the machining was done in-house. Add a bit to amortise your prototyping costs, and the rest is profit. Subcontract the intermediate cases out. Low volume, low overheads - the key to undercutting the traditional transaxle manufacturers ...
Why haven't I given it a go, or at least done more research? I'm up to my upper hair folicles in full time work, kids and building my own prototype production car. But if one of you do it, I'll be your customer in a few years time.
So, do you think I'm a complete loon, or is there some merit (you can read genius if you want)?
From my reading on the forum, the availability of 2nd hand G50s isn't what it used to be. I would imagine the current crop of suitable Audi boxes will begin to dry up eventually, too.
There are also people out there who (I assume) would like a new transaxle for their GT40 / Lola / Ultima etc, but price is a major barrier.
In Australia, a new Porsche gearbox is around $18-$23K depending on model. I imagine a new ZF or RBT-6 is somewhere in that ball park. Mendola is at the lower end of this range, but unproven in an application of the kind we are interested in AFAIK. I don't know the cost of the new Xtrac transverse transaxle.
There is a lot of amazing engineering experience on the forum. So, why hasn't someone designed, built and profitably produced a strong 5 or 6 speed transaxle with decent gearing for under US$10K?
Don't shoot me down just yet - listen to my idea. You've may have even thought of it yourself...
Build a prototype based on 2nd hand Tremec or Richardson etc. Make a longer input shaft. Or, even better, make an input shaft extension. Then put a hole in the front of the gearbox and attach an extension for the output shaft (that goes on to the front rather than the rear of the shaft) with a gear on the end. Set an equally strong ATB diff between the 2 shafts (or above the output) with a gear on its input. The diff sits the correct way round and is driven from the gearbox output shaft extension via a reversing gear, so everything spins in the right direction.
I'm sure you can see where I'm going with this. I never said there wouldn't be a lot of machining involved!
Make a frame to support all of this and to take a bellhousing at the very front, over the input shaft extension. Once all the mounting points are properly located relative to each other, have a think about the stresses involved, and use your CAD experience to knock up a case design that mounts between the bellhousing and the gearbox, and that carries (and oils) the diff, and locates and seals all the shafts etc.
You can now produce new transaxles using commercially mass produced bellhousings, gearboxes and diffs, with you supplying CNC'd input and output shaft extensions and the intermediate case, and machining any necessary parts of the gearbox. You could go the whole hog and do a completely new case, but I think that would merely cut into profitability.
Oh, and you might want to consider a business plan before doing any of the above! I'm making assumptions about the costings, but would imagine a unit using new parts would cost less than US$6,000 if much of the machining was done in-house. Add a bit to amortise your prototyping costs, and the rest is profit. Subcontract the intermediate cases out. Low volume, low overheads - the key to undercutting the traditional transaxle manufacturers ...
Why haven't I given it a go, or at least done more research? I'm up to my upper hair folicles in full time work, kids and building my own prototype production car. But if one of you do it, I'll be your customer in a few years time.
So, do you think I'm a complete loon, or is there some merit (you can read genius if you want)?