So I know that you can flip VW transaxles around so that the input shaft points inside the vehicle. Something about flipping the ring gear, but it leads to issues with longevity on the gear surfaces, and shifting problems? How can you get around these, and what sort of HP can these transaxles hold up to (barring Wreck Racing style launches)
Call rancho performance in fullerton Ca ,
714 680 6737
They have been building VW transmissions forever , Offroad and drags , or just a street trans.
I'm talking Challenge level stuff, folks. Not anything high dollar.
I did the ring gear flip years ago on a Solo Vee and have never heard anything about it reducing transmission life. It was very easy to do though. The shift linkage needs to be well made if you do it with rods, no slop allowed. I have seen it done with cables but have no direct knowledge of that method. I was running a pretty stock 1600 engine (header and twin SUs) so busting the trans wasn't really a consideration
I'm no expert, but most of the flipped transaxles I've seen have been in sand rails and few had more power than an NA corvair 6 being shoved in. I would imagine most applications are similar, and if such lightweight low powered vehicles give a reputation for things wearing out...
That said, I know the hardcore vw race guys prefer the swing axle variants. For hard launches they seem to be stronger, though the weak link may be more in the axles/joints than the trans itself.
For a vw based challenge entry, I've often thought about how I'd approach it. Finding a used set of forged pistons and applying boost seems to be the answer. Lock the 009 dizzy at 22*, find a Holley 390 carb, jam 18psi in, party. One could juice 150 wheezing ponies, especially with a bottle. Keep the weight down. It's just that the cars are getting so damn expensive.
If memory serves me, too much power will break the trans housing before it strips the gears. Back then (mid-eighties) the drag Bug guys were using bus transmissions because they had a stouter case.
Edit: The Corvair engine rotates in the opposite direction to the VW so conversions to the Corvair required a ring and pinion flip to avoid having 1 forward and 4 reverse gears.
When I built up the Wartburg with VW/Subie power I consulted our local guru/old head on the transaxle. He was a top tier drag racer in his day so his knowledge is based on experience. He said 250hp is a safe number for a stock transaxle. You WILL break CV joints if you launch too hard or without some finessed but he said (and I totally agree) that's your "fuse" in the system. Cheaper and easier to pop new CVs in than rebuild a transmission.
The early busses (pre-67) in the US market had the ring gear flipped from the factory because of the reduction boxes at the wheel end of the swing axles.
The later busses had an 002(?-not sure as memory is fading ) irs transmission that was popular with buggies, but I’m not sure the ring gear could be swapped.
the early swing busses had a 3.73 gear and the bugs had a 4.10 as I recall. In the seventies people swapped bus transmissions in to get “freeway flier” gears in their bug.
I have a mid engined rail, with the trans I just flipped the differential as the swing axle trans the pinion is on the centerline. Mines mated to a 170bhp 2110cc type one and used for off road, never had an issue. I think you can do similar with an IRS, but its a little more complicated as the pinion isn't on the centerline (I may be wrong)
Look at Hewland boxes used in all sorts of 60's/70's GT's etc.. they're basically VW transmissions...
Bus trans is stronger.
Porsche 914 901s already have it done.
Subaru 5spd with a subarugears reverse R&P?
preach (fs) said:Subaru 5spd with a subarugears reverse R&P?
For MR all you need is a Angle Grinder, TIG welder (Mig would probably be fine) and a Frying pan to cover the hole.
I modified mine for $2. The trans drops 27 lbs and loses 8" of length in the process. The shifter shaft seal is in the transmission so you just need clearance making the plate easy to Fabricate.
For RR there is probably better options then the Subagears conversion unless you are using a Subaru Engine or want to keep AWD.
As someone who is partway through a Subagears conversion, it's not the Challenge option. But it's the right choice for my application.
On a completely and utterly unrelated note, I will have a 1985 Vanagon transmission available at some point in the future ;)
Yes I was saying for challenge RR applications there are better options then the subagears. I will be interested to see your thoughts after your subagears conversion is done Kieth.
Are you doing 2WD or is AWD conversion happening?
For the challenge, definitely. There's no way you could do the Subarugears on a Challenge budget and doing a custom reverse R&P is not really something you can diy at home super-cheap. Well, I say that. Someone prove me wrong!
In my case, it's for a Westfalia camper. If I get into a position where I need AWD things are not going according to plan :) I'm not even installing an LSD for the same reason. I just want the strength and the gearing - my modified 6-speed will get me a new gear in the chasm between the VW 3-4 plus a total cruiser top gear. We'll see how the new high compression 2.5 pulls that tall 6th. I do have a friend who has long-term plans to do a Synchro Vanagon with the Subaru trans, though.
So far, it's been a bit of a rocky road. Incorrect parts shipped, I've paid for parts that I can't use (why did they include a $200 5-speed bracket in the kit if there's no way it'll ever fit the 6-speed?), some of the included tools were manufactured in a way that prevents them from being used and it appears there are errors in the instructions that lead you to incorrectly assemble the pinion gear. I ended up taking the trans to a pro to get it set up properly, and he found the assembly problem on three subagears transmissions that were in the shop at the same time. I have spent far more money on this than I originally planned and I still have to figure out my own shift cables and transmission mounting. The 6-speed is a bit of an orphan. Still, I am looking forward to the end result.
For fun and to give a size comparison and because it's here on my phone, here's my six speed (on left) compared to a couple of five speeds.
A 6 into a Vanagon? Impressive sir.
Don't get impressed until I actually manage to do it :) There shall be welding.
And I have been playing with a Hewland MK III, five-speed transaxle. This what the Elva factory ran at Sebring in 1962.
Scott Young rebuilt it. I was loaned some original side covers that Tom and I will duplicate to mount the original inboard drum brakes. Some very trick stuff, that still uses an early swing axle VW case. Now we need to figure out how to modify the nose cone and figure out stub axles.
Here's a pic from the April 1962 issue of Sports Car Graphic that shows how the car is configured, and here's a pic or two of what we have now.
And just for kicks, here's a picture of the Roltek, Super T10 for the Mustang project, becuase how weird is it to have two super trick transmission on teh bench at the same time. Got to be a first in my strange life.
In reply to Tim Suddard :
That first pic is sexy as hell.
In reply to Mr_Asa :
Thanks. it is a strange deal and parts and info are pretty much unobtanium. Still, I am fortunate to have most of the original parts and am finding a network of sports racer and Elva experts. Elva morphed into McLaren, by the way. And here is a pic of the car as raced at Sebring in 1962.
Any pictures of the inboard rear brakes ?
what drum did they use ?
In reply to californiamilleghia :
It appears to be an early Rootes group product. Possibly Alpine rears. Maybe earlier front drums from another Rootes group product.
In reply to californiamilleghia :
I'll get pics of the brakes, once I get them organized a bit further.
Tim Suddard said:In reply to californiamilleghia :
It appears to be an early Rootes group product. Possibly Alpine rears. Maybe earlier front drums from another Rootes group product.
The lack of confident statements makes this sound like a really interesting project :)
In reply to Keith Tanner :
Learning is always a process when you are working on a car that is 60 years old and only 28 were built.
I know the OP saw this at the Challenge but here is the Subaru Transmission post-modification from a similar view as the Elva (Which is so cool we need a build thread).
You can see the starter is High and to the left. The stock starter is tight to the transmission. Cable and hydraulic clutch actuators are available and are tranmsission mounted. Weight post 2WD conversion is ~75lbs which seems "typical" for a Transaxle. I can get better pictures and dimensions if people would like.
The rear mount shifter can be a challenge with the Subaru transmission (and really can be for all the non Porsche Boxster sourced Transmissions). There are not any "off the shelf" cable shift components available so you are on your own. The FF818 folks use Boxster cables and have some aftermarket billet aluminum stuff they use. I used a fairly complicated linkage I fabricated that I documented in my build thread.
You'll need to log in to post.
