midengine mopar
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A few questions. Where do you want the axles to be in relation to the engine bell housing?
Most inline transaxles have axle shafts just aft of the clutch. If you can deal with extra distance, a regular manual trans with a 4 wd adapter coupled directly to a IRS diff would work. ( A Ford T bird would be a good choice as limited slips and good gears can be gotten, a 79 / 86 Toro diff could be adapted as the splined shaft is the same as a regular trans. ) Mark Williams makes couplers to get you from the trans to the diff, however that would only work if the diff and trans are solidly mounted.
The Toro trans came in a few sizes, these mount the engine front to back.
66 to 78 ish was a TH 400 with a chain connecting the torque converter to the trans. The actual gear train runs along the left side of the engine then the diff is bolted about where the front of the engine is. ( No idea is the internal diff parts are similar to a rear drive posi)
79 to 86 ish was a TH 200 ( and later 200 4R 4 speed ) some configuration as the older units but lots lighter. The Grand National turbo guys put big power through the 200 4R and many parts will interchange. ( the sprag is built backwards so don't swap them ) Internal parts from a 7.5" might fit ( Posi carrier)
The Fiero uses " Parts Bin Technology " The trans is just a regular front drive Citation / Cavalier trans. The engine is mounted left to right, this puts the gear train behind the engine. The engine is mounted left to right. Posi is not available.
Chrysler LH series cars late 90's mount the engine front to back but only a auto trans can be gotten. This is the same trans used in the front engine / rear trans axle Plymouth Prowler. Someone was making a posi for these but expect to pay big $ )
Porsche 924 / 944 / 928 all have a front engine / rear trans axle. The 924 and likely 944 cars used a Audi front drive trans. These still retain a full bell housing on the trans. Posi is out there.
The V8 powered 928 uses something special. This trans has a rubber doughnut to couple the trans the drive shaft. Posi is probably out there for these too.
Most inline transaxles have axle shafts just aft of the clutch. If you can deal with extra distance, a regular manual trans with a 4 wd adapter coupled directly to a IRS diff would work. ( A Ford T bird would be a good choice as limited slips and good gears can be gotten, a 79 / 86 Toro diff could be adapted as the splined shaft is the same as a regular trans. ) Mark Williams makes couplers to get you from the trans to the diff, however that would only work if the diff and trans are solidly mounted.
The Toro trans came in a few sizes, these mount the engine front to back.
66 to 78 ish was a TH 400 with a chain connecting the torque converter to the trans. The actual gear train runs along the left side of the engine then the diff is bolted about where the front of the engine is. ( No idea is the internal diff parts are similar to a rear drive posi)
79 to 86 ish was a TH 200 ( and later 200 4R 4 speed ) some configuration as the older units but lots lighter. The Grand National turbo guys put big power through the 200 4R and many parts will interchange. ( the sprag is built backwards so don't swap them ) Internal parts from a 7.5" might fit ( Posi carrier)
The Fiero uses " Parts Bin Technology " The trans is just a regular front drive Citation / Cavalier trans. The engine is mounted left to right, this puts the gear train behind the engine. The engine is mounted left to right. Posi is not available.
Chrysler LH series cars late 90's mount the engine front to back but only a auto trans can be gotten. This is the same trans used in the front engine / rear trans axle Plymouth Prowler. Someone was making a posi for these but expect to pay big $ )
Porsche 924 / 944 / 928 all have a front engine / rear trans axle. The 924 and likely 944 cars used a Audi front drive trans. These still retain a full bell housing on the trans. Posi is out there.
The V8 powered 928 uses something special. This trans has a rubber doughnut to couple the trans the drive shaft. Posi is probably out there for these too.
Another way to go about this altogether is to just use a normal Mopar V8 and a conventional four or five speed reversed in the chassis. Fit a 4WD transfer case to the front of the gearbox, and take a drive shaft to the back (beside the sump) to drive an offset rear diff.
This is really just the typical standard 4WD SUV arrangement completely reversed in the chassis. The SUV front axle location becomes the rear suspension of a mid engined car.
The only requirement is to, once again, reverse the rotation of the rear diff. An independent rear suspension with an offset diff should work. And inverting the diff will reverse the rotation.
Even the Bugatti Veyron is built like that. Notice the rear "tail shaft"
Placing the gearbox right at the back of the car in the traditional mid engine position creates a huge problem for the gear linkages. Even the worlds best sports cars have now given up on the rear mounted gearbox gear linkage problem.
Mid engined McLaren , Ferrari, and Lamborghini all now have the gearbox placed in front of the engine, it makes a huge difference to the quality and feel of the gear change.
You can probably adapt a bunch of standard low cost SUV 4WD parts to do something fairly similar. It would be super strong, with plenty of choice of gear ratios, and the cost reasonable.
This is really just the typical standard 4WD SUV arrangement completely reversed in the chassis. The SUV front axle location becomes the rear suspension of a mid engined car.
The only requirement is to, once again, reverse the rotation of the rear diff. An independent rear suspension with an offset diff should work. And inverting the diff will reverse the rotation.
Even the Bugatti Veyron is built like that. Notice the rear "tail shaft"
Placing the gearbox right at the back of the car in the traditional mid engine position creates a huge problem for the gear linkages. Even the worlds best sports cars have now given up on the rear mounted gearbox gear linkage problem.
Mid engined McLaren , Ferrari, and Lamborghini all now have the gearbox placed in front of the engine, it makes a huge difference to the quality and feel of the gear change.
You can probably adapt a bunch of standard low cost SUV 4WD parts to do something fairly similar. It would be super strong, with plenty of choice of gear ratios, and the cost reasonable.
Cheers, Tony.
- BillyShope
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I'm sure you understand what's involved, but, judging from the responses in other threads when this subject comes up, I want to make it VERY clear that, when you move the complete FWD assembly to the rear, you don't need to worry about reversing the rotation of anything. Don't know why there's so much confusion, but, as I said, I've seen a lot of it in other threads.Warpspeed wrote: Another way to reverse the rotation of any transaxle is to....
If I were a young man, I'd consider a project like an old VW bug with a modern DOHC 4 cylinder FWD assembly at the rear. Sort of a "poor man's 911." Or, how about doing the same with one of the early VW vans?
http://home.earthlink.net/~whshope
as a young man of 48 i always loved the sound of a hi revin 340
and want to build a can am style retro my own panels and such
as i live not to far from road atl thought someday i could drive it
there
and want to build a can am style retro my own panels and such
as i live not to far from road atl thought someday i could drive it
there
if from now on you blame anything on anybody
it might be the alien spores from the meteors...
http://www.wallaceracing.com/Calculators.htm
it might be the alien spores from the meteors...
http://www.wallaceracing.com/Calculators.htm
Simple Billy, most Porsche gearboxes come from REAR engined cars. To turn the whole mess around to make it MID engined, the rotation needs to be changed. Porsche boxes are designed to do this.BillyShope wrote:I'm sure you understand what's involved, but, judging from the responses in other threads when this subject comes up, I want to make it VERY clear that, when you move the complete FWD assembly to the rear, you don't need to worry about reversing the rotation of anything. Don't know why there's so much confusion, but, as I said, I've seen a lot of it in other threads.Warpspeed wrote: Another way to reverse the rotation of any transaxle is to....
If I were a young man, I'd consider a project like an old VW bug with a modern DOHC 4 cylinder FWD assembly at the rear. Sort of a "poor man's 911." Or, how about doing the same with one of the early VW vans?
A gearbox from a small front wheel drive car is not going to work with a large capacity high output V8 engine. Strength is obviously not there.
Yes it is possible to just move everything from a front wheel drive car to the rear of the car as you suggest. The number one problem doing that, is always that the gear change mechanism comes out of the gearbox about where the rear number plate has to go. Constructing a mechanical or cable linkage to go right around the gearbox and engine is not as simple as it might at first appear.
Another detail overlooked by some, is that differential gears have a preferred direction of rotation. The teeth are not symmetrical. You cannot rotate these gears backwards and expect the diff to survive for very long.
The way to reverse the rotation is to place the crown wheel on the opposite side of the pinion, or in other words just turn the whole diff upside down. The only difficulty is that the pinion may then be at the top of the diff casing, high and dry out of the oil. This may or may not be a problem for the front pinion bearing, but at the very worst, an external oil pump may be required, but often it works fine as it is.
Cheers, Tony.
Been there, done that. 26 years ago, when I was a pup. I'm smarter now.Warpspeed wrote:That is true. The only real problem with the Toranado layout is that the engine sits beside the transaxle, making for a very wide and asymmetrical layout.
The trans actually hugs the side of the engine pretty tight, not that wide... the 911 axles were only narrowed about 4" on each side... and it is not asymetrical; the CV flange on the right side is the same distance from engine centerline (after passing though the oil pan) as the left one.
Oldsmobile 455 V8
[size=150][url]http://www.SportsCarDesigner.com[/url] [color=deeppink].... You [u]want[/u] to design your own car... so go ahead.[/color][b] Sports Car Designer [/b][color=deeppink] is the answer.[/color][/size]
What else can you do with that gift card you got?
What else can you do with that gift card you got?
That would be a LOT of added wheelbase!Masher Manufacturing wrote:Most inline transaxles have axle shafts just aft of the clutch. If you can deal with extra distance, a regular manual trans with a 4 wd adapter coupled directly to a IRS diff would work.
Actually the axle passes through the oil pan (or under, can't remember which) at the middle of the engine... 4 cylinders ahead of axle centerline, 4 cylinders behind.Masher Manufacturing wrote:The Toro trans came in a few sizes, these mount the engine front to back. 66 to 78 ish was a TH 400 with a chain connecting the torque converter to the trans. The actual gear train runs along the left side of the engine then the diff is bolted about where the front of the engine is. ( No idea is the internal diff parts are similar to a rear drive posi)
[size=150][url]http://www.SportsCarDesigner.com[/url] [color=deeppink].... You [u]want[/u] to design your own car... so go ahead.[/color][b] Sports Car Designer [/b][color=deeppink] is the answer.[/color][/size]
What else can you do with that gift card you got?
What else can you do with that gift card you got?
- BillyShope
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Yes, I understood where you were coming from, Tony, but, as I thought I made clear, I didn't want anybody to get the idea that rotation direction is always a problem.
And, there are options to the Toronado. The Mopar line, in particular, has a number of FWD's with big engines. Big, certainly, in comparison to the engines originally coupled to the Porsche transaxles.
Yes, shift linkage would be a challenge, but certainly not an insurmountable one.
And, there are options to the Toronado. The Mopar line, in particular, has a number of FWD's with big engines. Big, certainly, in comparison to the engines originally coupled to the Porsche transaxles.
Yes, shift linkage would be a challenge, but certainly not an insurmountable one.
http://home.earthlink.net/~whshope
Like Engine Guy, all this insane mid engine stuff for me goes back to my mis spent youth. Back then there was not a lot of gearbox choice.
Today, if I was doing this, I would probably use a late model 4WD system with both diffs inverted, and end up with something pretty much like the Bugatti Veyron layout.
.
Today, if I was doing this, I would probably use a late model 4WD system with both diffs inverted, and end up with something pretty much like the Bugatti Veyron layout.
.
Cheers, Tony.
Audi's run V8's and TDI's with quite a bit of torque with the engine in front and the transaxle just after it.. the first thing you find in those after taking off the front bumper is the engine. But,as you say,linkage might be a problem.Warpspeed wrote:A gearbox from a small front wheel drive car is not going to work with a large capacity high output V8 engine. Strength is obviously not there.
-Bjørn
"Impossible? Nah...just needs more development time"
"Impossible? Nah...just needs more development time"