So I had this silly thought of whether or not you can use a 4wd transmission and transfer case for a mid engine setup. Basically, block off the rear output and run just the front similar to the Olds transmission in the Toronado. This might be an inexpensive way to LS something with a paddleshifted auto. I also have access to an old chevy half ton with a 5 speed manual that would make a killer donor. TBI but its still a 350 so you know, parts supply.
I assume you are thinking of mounting the drivetrain transverse? That setup would be pretty wide.
You probably could... I feel like getting the engine low enough to have a reasonable CG height would be a challenge.
havent people run subie engine and trans like this is VW's? the front axles are the rear on the VW.
You'll need one with a gear reduction similar to an axle (3.0:1 ) and you'll need to find one with a differential.
Or are you thinking about making the rear drive shaft the front drive shaft and the front the rear, and let the engine land where it may?
No, what I am thinking is taking the entire front end from say a Trailbazer and sticking it in the back of something (this is a long example). This would use the front diff, half shafts, control arms, etc. set in the standard layout of that particular engine but placed behind the front seats and with the rear output deleted. No additional axle, no reductions required (run in the high position if multispeed transfer case). I am thinking cut and paste.
In reply to singleslammer:
I could see this working OK for some kind of buggy or other offroad rig. You'd probably want to take apart the transfer case and lock it into 4H, not to mention remove any other non-useful rotating mass.
Subaru engines and gearboxes are used this way. See Factory Five 818 for an example.
I know, I am just curious about issues with this type of setup because around here rusted out 4wd trucks are way cheaper and easier to source than subbies. Also, tasty, tasty V8.... oh yeah.
Hey, you know what has enough vertical space for this and a venue to race it which includes guaranteed magazine coverage?
Soccer Mom Class Domination
I'd help, but I'm a long way from you. Tow the van here with your donor truck and let's get to work!
A transfer case is really simple. It's basically just a two speed transmission with two sets of gears for output. At least the old school ones are. If you want a plug and play the NP203 used in the 70s was all time awd.
Here is an Ok example of a donor.
http://columbiamo.craigslist.org/cto/5377728562.html
These are fairly common around here. Also, it would be really easy to just buy a complete drop out from a junk yard for fairly cheap.
Should be no problem to drive the rear diff off the front output. Lock it in 4HI and go. You could also use a normal rear axle flipped around. No huge problem spinning a hypoid diff backwards (does lose some strength though), I've read that a lot of the old full size Jeeps did that. You could also get reverse cut gears if it bothers you.
Only issue I can think of would be heat, and that's easy enough to deal with (added cooler of some sort).
Ford 8.8" had both rotations. I wonder if you can swap a rear axle's gear to the front?
Any issues with torque handling? For example, in the 5-speed TBI SBC case, if you use the stock t-case locked in 4 hi, no rear axle...can the stock setup generally handle 100% (or in a modified case, more than 100%) of the designed total torque for all 4 wheels? I know it would vary on a case by case basis, and Subarus seem to be just fine with it, but that would make me nervous.
Good point. A lot of the truck cases drive the front output with a chain, so while it'll likely handle the power, there will be issues with wearing the case out. And most of the older gear drive units weigh a crap-ton.
In reply to rslifkin:
I'm reading 140lbs on a NP205 (the common beefy iron gear drive unit), versus 80 or so for your typical aluminum jeep Tcase. 60lbs down low and near the driven axle isn't the end of the world.
What about an Audi gearbox - even a 2wd? Some of the gt40 crowd use them as a budget approach to a Porsche g50. Busted audis aren't too hard to find on the cheap
Kenny_McCormic wrote: In reply to rslifkin: I'm reading 140lbs on a NP205 (the common beefy iron gear drive unit), versus 80 or so for your typical aluminum jeep Tcase. 60lbs down low and near the driven axle isn't the end of the world.
That sounds about right. The lightest decently strong case I know of is the NP231 at 65-ish lbs (dry).
All you would have to do is put the transfer case in 4wd as long as the rear output shaft remains in place. Without the drive shaft. That would make a really compact set up. As the front drive shaft goes along side of the engine.
gearheadE30 wrote: Any issues with torque handling? For example, in the 5-speed TBI SBC case, if you use the stock t-case locked in 4 hi, no rear axle...can the stock setup generally handle 100% (or in a modified case, more than 100%) of the designed total torque for all 4 wheels? I know it would vary on a case by case basis, and Subarus seem to be just fine with it, but that would make me nervous.
I think any decent transfer case would be able to handle the power, you have to think too even though its seeing the full torque of the engine it also only has half the traction, powering 2 wheels instead of 4. Like how when people use the subaru 5 speed, which is notoriously weak, for 2wd mid engine applications and it holds up well.
also as long as you keep the fluid fresh in the transfer case i wouldnt worry about the chain. chain drives have been used in a handful of other fwd trans and do fine under power, such as the old TH425's and the 4T65E in the grand prix's. If people can be bouncing there 4wd at WOT up a rock ledge and the transfer case can take it then it should be fine in a 2wd application.
also i saw you said you wanted to start with a 5 speed 1/2 ton chevy. those use the nv3500 trans and they are not known for being very stout, just something to be aware of.
edizzle89 wrote: also i saw you said you wanted to start with a 5 speed 1/2 ton chevy. those use the nv3500 trans and they are not known for being very stout, just something to be aware of.
I think most of those failures were from incorrect fluid or general abuse. They only take GM/Pennzoil Synchromesh fluid, which is 10w30 with an additive package. The only failures I'm aware of had gear oil in them, which starves the bearings. This results in intermediate shaft failure, causing the teeth to go tip to root. If the transmission whines, those bearings are toast. Excess driveline lash is also common in the NV3500, especially the early ones. This can also be, but isn't always, caused by the bearing failure.
I have a 1989 NV3500 in my caprice wagon, behind an SBC that makes something between 350 and 400 hp. It has 180k+ miles on it, and I broke the yoke on the old driveshaft without failing the trans. I think they're sturdier than most people give them credit for.
/thread jack. 
Hey, this might be relevant. Georgia Tech's Wreck Racing team brought a (mostly finished) mid-engine Honda Insight to the Challenge last year. It uses a Subaru engine and manual trans, with the rear output deleted so that the front outputs drive the rear wheels. I think that's what you're going for here.
I was on the team and did the transmission conversion. Basically you just weld the center diff and throw it back in. No V8 powah, but it is mated EG33 (flat 6-cyl) from a junkyard SVX, so that's something.
I am familiar with that car and it is definitely cool. However, I am just thinking this through with readily available truck packages. The EG33 is pretty scarce around these parts. I am not planning anything just thought this would be an interesting topic of conversation. So the consensus is that if you just weld the center diff up and block off the rear output, it should pretty much work. It will have the crappy (potentially) truck suspension and weigh a ton but it would "work."
If you get a part-time 4wd setup, not AWD or full-time 4wd, then there isn't a center diff, both outputs turn the same when in 4wd mode. Plenty of off-roaders have made it home on just the front drive, so it should work for you. If the transfer case has a bolt-on rear output yoke, then you can just let it hang out. Be interesting to see what you come up with.
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