Transaxles for Longitudinal Mid-engine Setup

Curmudgeon wrote: I think the shifter will be a problem with the 944 etc transaxle since it goes through the bellhousing right where the flywheel clutch etc need to reside. Not insurmountable, though.

I would think that could be fixed with some simple fabrication of the shift rod. An offset in the shift rod and problem solved. Wait it would some how have to get around the motor yes? I wonder if there is some sort of cable shifter that could be adapted. Thinking about this more it may not be that simple. I think I have the shifter setup from an MR2 lying around I should look at that and see how adaptable it would be.

kb58 wrote: I've rolled the idea of a typical mid-engine V8 car around for about 30 years. Never did it because I kept coming back to only one solution, a proper but expensive Porsche transaxle. Because of the very high cost I ended up just building lighter cars and using an entire FWD assembly. You might look into using the entire FWD package from something like the Cadillac SVCC-SCI... or whatever they call that 500hp version... Yeah I know the engine's sideways, but either you have to compromise, or pony up the money to do it the way you want.

That's what first popped into my head, those FWD transverse-mounted V8s in some Caddies from the '90s. There's zillions of those with automatic transmissions available. And, as I have recently learned, an automatic transmission with a shift kit isn't such a bad thing at all.

Chrysler A606/42LE?

http://en.wikipedia.org/wiki/Ultradrive#A606.2F42LE

Used in LH series front drive cars, and, surprisingly (to me) the Prowler.

I'd assume, based on the kind of power attached to these at the factory, that it's possibly not stronger than other options above, but it's plentiful and cheap. I would not be surprised if some Prowler guys know just how strong it can be made to be.

Hey, check out this thread, specifically the Powerglide 'shorty' pic:

http://grassrootsmotorsports.com/forum/grm/the-maximum-minor-build/44305/page1/

Maybe longer than you wanted, but surely a ton cheaper than some other solutions .

Edit: Hmm, maybe not cheaper, I just looked at some 'shorty' prices.

IIRC the Acura Vigor has a transaxle very similar to the Legend, it was a 5 cyl and was available with a manual. But it too was pretty rare.

Two-cable shifters aren't that hard to find. PT Cruisers and Neons had them. The cables for them are probably way too short for a mid motor build, but Morse Cables can probably fab something up. I once worked out in my ugly head a rod-to-cable setup which might allow use of a set of the shorter cables. Never got a chance to test it for real, though.

OBTW, the Sterling was basically an Acura. If you can find one of those it would have the same transaxle. No idea how tough it is, though.

It's no problem getting longer push-pull cables. And it's surprisingly easy to switch things around such that the shifter works normal when the drivetrain's move to the rear. I figured it out the hard way on Kimini, and did it the easy way on Midlana

Like kb58 said, the shifter setup is actually not that hard. Additionally there are lots of turn key solutions if needed. Thank you kit car and dunebuggy people.

Apparently, the Audi 01E is similar enough to (if not the same as) the early Boxter 5 speed that it's shift box and cables can be adapted with little hassle. +1 for the Audi box and the VAG parts bin.

I've thought about transverse, but refuse to even think about automatics. That basically leaves the GM F40. It also limits me on how far in I can mount the suspension. I was planning on running Miata suspension front and rear. The rear suspension does not look like it would work well with a transverse setup.

Giant Purple Snorklewacker wrote: Does anyone know anything about the BMW X5 or 535Xi or 325Xi transaxles? In older BMWs they used mostly the same part in everything so it was overbuilt to handle the top of the range.

What I can say for certain:

They aren't transaxles so much as RWD transmissions with a front output sticking out the side, like basically every longitudinal AWD that doesn't stick the engine way out kissing the front bumper.

I've heard that the xi/ix transaxle is fairly weak. I don't think that the setup is conducive to disabling the rear output.

It's been a while since I've seen an X5, but IIRC it has a transfer case sticking off the back of a ZF trans, like a Cayenne/Touareg. Or an American truck, for that matter.

If you can take the weight, maybe a 4WD truck trans/transfer, and IFS front axle set-up? Certainly up to the power, but the trans will be entirely out the back of the axle.

Of course, you could front-sump the engine and move the axle rearwards, just shortening the driveshaft, and some low ranges might be fun on tight autocross courses if you like shifting.

oldopelguy: Do you mean something like this?

Saw that at a cruise-in last year. It was in the back of this.

Yep, and while you're at it look at the set-up on a trailblazer. The oil pan has the differential attached to it and running through it.

That's basically how the old wheelie trucks did it. They weren't exactly worried about having too much weight on the rear wheels.

Nobody has mentioned the Porsche G50 yet? Edit: I'm a moron, forgive me.

Other than the thread starter?

slopecarver wrote: Nobody has mentioned the Porsche G50 yet?

It's in the first post.

kb58 wrote: I've rolled the idea of a typical mid-engine V8 car around for about 30 years. Never did it because I kept coming back to only one solution, a proper but expensive Porsche transaxle.

Just recently I came up with a better solution, after much research!

Modded 2010+ Legacy GT 6spd or modded WRX STi 6spd. The STi box will handle 500hp+ stock. There are reports of them even standing up to nearly 700hp!

Downsides: The Legacy GT box won't handle big power, the STi box is heavy and long (even with the rear bit that you don't need in a 2WD application removed and capped off) and has super-duper-close ratios that you might not want. But the way I see it is, worst case scenario (say you change up the ratios ($$$) on top of the AWD-->2WD conversion), you end up with a gearbox that still costs less than a clapped-out Porsche box but is way tougher, and you can easily find cheap parts for.

Corvette box? That is a super-long setup, it will be nearly 5ft from your flywheel to your rear axle, not an option for most cars.

The Audi 016/01E also hold up to that kind of power.

(As long as it is a small displacement turbo engine!)

Just a friendly note, powertrain components like gearboxes and diffs are rated for torque not power.
And the real killer of such is transient shock loads due to lash in the driveline (Loose U-Joints or worn splines for example), where loads can easily spike at 5-10 x the steady state torque from the motor.
Also, a limiting factor is the amount of traction developed by the tires. Regardless of how much torque the motor can make, less traction = less peak torque load in the driveline. Hot rodders know, when you bolt on slicks and start hooking up, you start lunching tranny, diff, etc.

Carry on.

In reply to GameboyRMH:

okay, so on the Subaru boxes, what sorta torque do you think they would handle?

stroker wrote: In reply to GameboyRMH: okay, so on the Subaru boxes, what sorta torque do you think they would handle?

Found one guy saying his 6th gear (in the STi gearbox) let go running 700ft-lbs:

http://www.iwsti.com/forums/drivetrain-components/188927-how-much-hp-can-sti-transmission-hold-5.html

Most reckon the axles will let go first.

GameboyRMH wrote:

stroker wrote: In reply to GameboyRMH: okay, so on the Subaru boxes, what sorta torque do you think they would handle?

Found one guy saying his 6th gear (in the STi gearbox) let go running 700ft-lbs: http://www.iwsti.com/forums/drivetrain-components/188927-how-much-hp-can-sti-transmission-hold-5.html Most reckon the axles will let go first.

I'm smelling Kludge solutions...

It requires a lot of mods, but it's definitely a better deal than a Porsche box and at least on par with any Audi box (hope you like tall gears). There's a company that makes an AWD-2WD conversion kit for the Impreza 5spd box:

http://www.bremarauto.com/products/subaru-2wd-conversion-kit/

The mechanism to "spool" the front-rear diff in the STi box will be different, but other than that it's basically the same operation.

In reply to stroker and Gamerboy:

Did you take a look at the links I posted on page 1? I posted that link already.

GameboyRMH wrote: It requires a lot of mods, but it's definitely a better deal than a Porsche box and at least on par with any Audi box (hope you like tall gears).

Audis aren't geared very tall... at least, the AWD 016 in my car turns roughly 4000rpm at 70-75mph. 5th gear is overdrive on a technicality and it's a 4.11 final drive.

I'm unsure what the FWD 016s are at, but given the lack of variability in Audi transaxles of the timeframe, the tallest FD you'll see is probably 3.89 and overdrive is maaaaybe .8:1 at best.

TJ, I did take a look at those links and I've bookmarked 'em for future use. Thanks!