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oldeskewltoy wrote:Hmmmm, Toyota All-Trac Corolla....E55 transaxle,
not sure it'll work though.... it was designed to go up front, and drive the rear wheels via driveshaft
It won't work, that's why I made this thread.
I'm going to start looking at truck transmissions. At least they should be strong!
Ian F wrote:I've yet to see a transmission that wouldn't a) leak like crazyif installed upside down or b) self-destruct due to improper oiling.
I believe the Porsche G-50 can in fact be flipped, IIRC, there's a trick to it, let's it be used in a mid-engined car, as opposed to a rear-engined car. Cannot remember said trick, and I no longer have the boss that could give me the answer. If it wasn't the G-50, it was another of the 911 units.
However, this is useless for AWD, to the best of my knowledge.
mistanfo wrote: I believe the Porsche G-50 can in fact be flipped, IIRC, there's a trick to it, let's it be used in a mid-engined car, as opposed to a rear-engined car. Cannot remember said trick, and I no longer have the boss that could give me the answer. If it wasn't the G-50, it was another of the 911 units.However, this is useless for AWD, to the best of my knowledge.
I think you're right. I vaguely remember reading somewhere that some Boxster and 911's had essentially the same transmission but flipped. Or maybe it ws the 914-6 and 911?
oldeskewltoy wrote: said:Hmmmm, Toyota All-Trac Corolla....E55 transaxle,
not sure it'll work though.... it was designed to go up front, and drive the rear wheels via driveshaft
mr2peak said:It won't work, that's why I made this thread.
What MR2peak meant to say was that the MR2 Turbo uses the Toyota E153 transaxle, which is just the 2 wheel drive version of the Celical All-Trac transaxle. THey used the same engine as well. The All track was transverse front engine, front transaxle (like modern Evo's and WRX's), so that was his first thought, but he realized that the All-Trac has the drive shaft output facing to the rear of the car.
MR2Peak, I think there are a several options, but it ain't going to be what you want to hear:
1) the cheapest (but NOT cheap) is to just to forget mid-enigne, and go rear engine, and lift the engine, trans, driveshaft, and front diff from the Porshe all-wheel drive 911. This is the only time where I agree with Porshe's engine location. It really makes sense on an AWD car.
2) use any front engine with all wheel drive trans, but put them in the back of the car, then add a fabricated drive shaft that somehow takes power off of the rear output of the AWD trans. I envision a gear box attached to the output of the AWD trans, so the driveshaft will spin in the opposite rotation of the trans. THe driveshaft would extend forwards to the front of the car, and hook into a front diff that will accept power from the rear (the Porshe unit from 1) above comes to mind) Or, you could use a front diff from an IFS 4x4 small pickup truck or SUV. The driveshaft will have to somehow go under the engine and trans. Not good for ground clearance. I'm not sure of the rotations in this case. HOwever, if the rotation is not correct, then another rear diff can be used in the front, but another gearbox to couple the driveshaft to this diff will be required. It would reverse the rotation again.
3)Use a conventional longitudinal front engine/rear drive gearbox (that does not have an integral differential--not a transaxle), with a custom transfer case. This would be mounted behind the trans, which is behind the engine, which is mid-mounted. You could attach your own custom "transfer case" allowing for rear axle outputs, and an output that faces forward.
4) build an AWD trans from scratch, or see if the custom trans manufacturers like Mendeola, Xtrac, etc. are making anything like this. THis option is probably more expensive than just buying a used Lambo trans.
The previea all-trac system sounds interesting. Lift the whole powertrain, and put it in a lightweight sports car, possibly an exo-skeleton type of thing. I could not find a photo of the previa drivetrain, or a cut-away of the van. Can anyone find one?
I forgot option
5) Hybrid system. Electric motor on the front differential. Engine and trans in the normal mid-engine location. Power takeoff from the trans to the generator/alternator. Besides #1) mentioned above, this is probably the most pratical.
Wonder if you could lift two of the input shafts for a quick change rear end and fab up a simple box to mount them in? Simple way to gear gear reversal and offset.
6) Hydraulics. One engine mounted anywhere and four motors, one for each wheel. Include a battery pack from a Prius and a second pump with electric drive and you'd satisfy the green crowd along with having maximum torque at ZERO rpm.
The previa all-trac is just a 4 cylinder flipped on its side with a transmission, transfer case, and front and rear diffs. The only thing special/different about that drivetrain than a standard 4wd truck drivetrain is the engine being on its side so it can live under the front seats.
It appears Quaife might have an option
http://www.quaife.co.uk/catalogue/search/results/taxonomy:824,619,627
But at the price in British Pounds is 8,500+
AWD, Rear engine, nothing special about the running gear at all.
internetautomart wrote:
Just a normal 4wd truck style drivetrain reversed. For a home brew setup I think flipping normal diffs would solve the 5 gears in reverse/one forward problem.
Take your typical FWD engine and trans and turn it sideways and mount in the car. Use the axles as driveshafts to front and rear difs. (weld the transaxles spider gears to give a locker).
I dont know why i didnt think to bring this up earlier, but Chryco did this with a jeep concept and it almost made production.
Javelin wrote:The Subaru setup might also work. It's setup as a RWD transaxle with a forward output, that would stick the engine actually literally in the middle if you stuck the rear diff right off of the end of the trans.
Subaru is not mid engine. The motor hangs fully in front of the front drive wheels. The rear flange mating to the trans is about 4" in front of the centerline of the front wheels.
It could be awesome as a mid engine RWD, but not AWD.
If the Subie motor was moved back far enough to be be a mid engined car, the front CV's would need very radical forward angles and a u-joint (or 2) in the middle.
Not mid, but rear engine:
http://bringatrailer.com/2010/08/04/all-wheel-drive-vw-bug-rally-car/
VW Vanagon Syncro
I think some Kei vans and trucks are 4wd and mid or rear engined.
Toyota Previa is mid engined AWD.
GMC Syclone trans may also get you there (and handle a ton of power), but forget the budget.
I see 4 options:
1: front engine AWD setup with a transfer case on the rear drive output, if length is a concern most transverse front engine awd setups are shorter.
2: front engine fwd transmission with a locked diff and a chain drive running forward from the longer of the output shafts as long as it fits under the engine.
3: I don't really think it would work cheaply, easily or for very long in an everyday car but it would involve a bike engine in the passenger seat and a chain driven 4wd setup ala palatov dp cars.
4: some other setup involving a conventional front engine 4wd transfer case setup rotated 180 and flipped diffs.
Edit Lookey what I found!!!!
Vigo wrote:Take your typical FWD engine and trans and turn it sideways and mount in the car. Use the axles as driveshafts to front and rear difs. (weld the transaxles spider gears to give a locker).I dont know why i didnt think to bring this up earlier, but Chryco did this with a jeep concept and it almost made production.
I don't understand about the switching to North South vs. east west. What did they do to the tranny?
