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Fri Feb 19, 2010 1:21 pm

I am the shop forman at a subaru dealer so anything subaru is cake for me.

I have decided to do the subaru engine in my buggy and have a couple of questions.

1. Is there anything special that needs to be done to the VW trans? I run an IRS. I know about the adapter and getting the engine to operate properly is no prob.

2. Is the current trans mounts sufficent to support the wieght and operation of the subaru 2.5 engine or does there need to be reinforcments or engine mounts of some type made?
or does the adapter solve this issue?

3. What about clutch operation is there a kit? I assume there will be some work needed to make the clutch work properly. like the release fork for the release bearing.

thanks for any advise.

Fri Feb 19, 2010 1:23 pm

Here is some good reading over on the DuneBuggy Archives.
http://www.dunebuggyarchives.com/forum/board_show.pl?bid=25

Fri Feb 19, 2010 1:34 pm

the stock bug transmission wont handle the power of the subaru engine for long.
you will need to have the 3rd & 4th gear hubs welded and i reccommend a super diff. you might want to change the gear ratios too but that will depend on your application and tire size etc. you can also get chromoly gear sets that are much stronger.

with the kennedy adapter you will use a standard vw clutch set up. i recommend a stage 2 pressure plate and a kush lock disc. that is what i run and it holds well.

we sell the adapters at my work. and if we are run out of stock, most of the time we have them on the shelf within 1-2 days not the 3-4 weeks that kennedy takes.

Fri Feb 19, 2010 1:39 pm

thanks for the info

Fri Feb 19, 2010 2:12 pm

Here is our build. We put a 2.5L STI engine in a Manxter 2 years ago. Some fabrication required! http://www.manxgallery.org/gallery/album437 Have fun with your conversion!

To specificly answer some of your questions. We used the Gene Berg mid mount and heavy duty rubber transaxle mounts. The chassis was a 1974 so the front mount was different. This seems to be working OK. With the Outfront adatpor & flywheel there was only one clutch issue with the bellhousing. A type 1 bellhousing will not easily accept a 225 MM stage 2 clutch. Much clearancing was involved. A type 2 bus transaxle would not be an issue. Tom

Sat Feb 20, 2010 4:43 am

The oil pan will have to be modified for ground clearance and the rear torsions will need to be replaced with larger diameter torsions or cranked up a spline or two.

Sat Feb 20, 2010 5:44 am

Or instead of having to get an adaptor plate, shortened sump, shortened headers, welded 3rd & 4th chromoly gears, a super diff and a custom flywheel you could just consider using the 5 speed Subaru transmission that comes with your engine. Just a thought for your consideration set.

Sat Feb 20, 2010 9:11 am

Original Manx wrote: Or instead of having to get an adaptor plate, shortened sump, shortened headers, welded 3rd & 4th chromoly gears, a super diff and a custom flywheel you could just consider using the 5 speed Subaru transmission that comes with your engine. Just a thought for your consideration set.

Being Subie motor is front engine, front wheel drive, wouldn't Subei trans turn wrong way in rear engine application..... Seems to me somebody was selling a reverse rotation R&P for such a application....

But it does lead to interesting mid engine possibilities...

Dale

Sat Feb 20, 2010 10:10 am

Dale M. wrote: Original Manx wrote: Or instead of having to get an adaptor plate, shortened sump, shortened headers, welded 3rd & 4th chromoly gears, a super diff and a custom flywheel you could just consider using the 5 speed Subaru transmission that comes with your engine. Just a thought for your consideration set.

Being Subie motor is front engine, front wheel drive, wouldn't Subei trans turn wrong way in rear engine application..... Seems to me somebody was selling a reverse rotation R&P for such a application....

But it does lead to interesting mid engine possibilities...

Dale

Dale -

The commenter posting above you is selling the reversed ring & pinion gears for the Subaru transmission to allow installing the Subaru trans into VW pan...

bnc

Sat Feb 20, 2010 10:18 am

There are specially cast replacement bellhousings and replacement input shafts which allow the direct installation of a Subaru engine on a bus transaxle using the stock Subaru flywheel, clutch and starter. They are significantly better than the adapter kits.

http://www.rjes.com/

Sat Feb 20, 2010 10:25 am

didget69 wrote: Dale M. wrote: Original Manx wrote: Or instead of having to get an adaptor plate, shortened sump, shortened headers, welded 3rd & 4th chromoly gears, a super diff and a custom flywheel you could just consider using the 5 speed Subaru transmission that comes with your engine. Just a thought for your consideration set.

Being Subie motor is front engine, front wheel drive, wouldn't Subei trans turn wrong way in rear engine application..... Seems to me somebody was selling a reverse rotation R&P for such a application....

But it does lead to interesting mid engine possibilities...

Dale

Dale -

The commenter posting above you is selling the reversed ring & pinion gears for the Subaru transmission to allow installing the Subaru trans into VW pan...

bnc

Yah missed that line in his signature...

Dale

Sat Feb 20, 2010 11:44 am

Dale M. wrote: Original Manx wrote: Or instead of having to get an adaptor plate, shortened sump, shortened headers, welded 3rd & 4th chromoly gears, a super diff and a custom flywheel you could just consider using the 5 speed Subaru transmission that comes with your engine. Just a thought for your consideration set.

Being Subie motor is front engine, front wheel drive, wouldn't Subei trans turn wrong way in rear engine application..... Seems to me somebody was selling a reverse rotation R&P for such a application....

But it does lead to interesting mid engine possibilities...

Dale

yea but the $5000 ring and pinion and fab work seems like alot more time and money to me.

Sat Feb 20, 2010 2:33 pm

I'd look pretty hard at that option if doing a rear engine car with Subaru engine in mind. You'd basically start out with a Subaru engine and WRX trans, using factory clutch options. Gearing and power handling capability already well matched to the Suby power curve, no bellhousing adapter needed.
Should run about $2G's for the reverse cut R&P and output flanges. Figure in some additional $$ to have the diff installed and set up, plus a mild trans going over. Oh yea, you'll need to special locking collar to make it FWD I think those run about $250 or so? Don't forget, this gets you a 5-speed conversion in the process! A bit of extra work though fitting the trans to the chassis and working up a shifter and linkage (sounds like a fun project to me!).

Now compare to nicely built T1 box - about $1k-1.2Kor so? Still, will it be strong enough? Plus adapter kit with HD clutch - $500. Not quite a wash price wise, but still worth considering - especially if you're thinking you'll need an LSD to go with the swap, then you're likely well ahead going all Subaru drivetrain. Plus a Berg 5-speed conversion??

Jeff

Sat Feb 20, 2010 4:17 pm

Normally aspirated RJES bellhousing kit is about $750.

With the power/torque of a Subaru engine in a buggy, I'd rather have the wide variety of R&P options with a Type 2 trans than the one 3.9:1 reverse cut R&P ratio in Subaru trans with a 5 speed. There's also a variety of off the shelf mounting, linkage and axle options available for putting a Type 2 trans in a Type 1 chassis.

http://www.rjes.com/html/prices___ordering.html

Sat Feb 20, 2010 6:07 pm

Reverse subaru ring and pinion are available in 3.9, 4.1 and 4.4 final drive ratios. Same as Subaru factory ratios, with more to come. How many final drive ratios do you really need? Remember this has FIVE gears not 4 so it covers a wide spread. Remember this is the Subaru box that actually matches the engine that you want to put in, not some mismatched vw 4 speed designed for 36-100hp.

I still can't understand why some vwers think a vw box is better suited to the power/torque characteristics of a subaru engine than the factory gearbox that a whole team of engineers at Subaru worked years on. I'm happy to be corrected if I'm wrong and sorry if I seem to be pushing my own barrow a bit here. It's just that the Subaru engine/box combo makes such clear sense to me.

As for cv/axle combos we have that covered. Releasing the new Subaflange shortly. It's a Subaru output flange that allows your current type 1, 4 or 930 cv and axles to bolt straight up. No need to change your setup. Same width from flange face to face as an 091 box with vw flange or type 1 box from flange to flange depending on where you put the roll pin through on the splines.

Sat Feb 20, 2010 6:34 pm

Your webpage says you have one ratio. If you have others on hand it should be updated. The reason people believe the Subaru engine and VW Type 2 transaxle is a good combination is because its been done hundreds of times with many thousand miles covered.

How many of your reverse ring gear conversions have been completed and put on the road? Any? What did they do to overcome the manual shift linkage challenges that come with putting a Subaru transaxle in the rear of a VW chassis. Any photographs?

Your project looks like it has great promise, and you deserve a lot of credit for trying it, but you should put a lot of succesful miles on your own test vehicles and all unforseen glitches found and resolved before its marketed. Other businesses have used their customers as their product testers and the results are never pretty.

Sat Feb 20, 2010 8:57 pm

And the Subaru gearboxes have weaknesses that are well detailed in various forums & magazine articles...

bnc

Sat Feb 20, 2010 9:04 pm

look in the offroad forum at skidmarks suby powred baja

Sun Feb 21, 2010 12:06 am

Guys, some good points raised there, I"ll try to address them.

You're right, there isn't even one reverse drive subaru box on the road yet. I only just started making these. Am building my demo box right now to go into a buggy with an EJ25 funny enough, exactly what this gent is asking about. Hope to be on the road in around a month.

Having said that, I don't see why you think there need to be hundreds installed to prove it works. There are hundreds of thousands of Subarus on the road that prove it works. We didn't change the design of the box, just made the diff flippable. If no one ever considers installing the Subaru box and just keeps recommending 091 boxes because they have been done before, how will the install base ever grow? There must be some early adopters out there that want to take a shot. I'd have thought someone who works at Subaru and has access to parts would be a prime contender.

You're right though the 091 box and Subie combo has been done hundreds of times, so that's definately the safe bet.

The many statements I've heard on various forums about the Subaru box being weak need to be taken into context. All gearboxes have weaknesses. How many VW boxes have blown to pieces? Millions.
Remember the Subaru gearboxes won eleventy million world rally championships in the Impreza WRX so they can't be all bad.

The reason they fail is because owners of 1500kg Subarus with 280hp (or boosted to 350 - 400hp) fit a button clutch, rev them to 6000 and dump them with their 4wd traction. Something has to give. This guy is fitting an ej25 (naturally aspirated I presume) that has 165hp into a 700kg buggy. So with half the power and half the weight, this transmission has a quarter of the stress. Plus with 2wd it will get wheelspin as well. It's not going to explode. It will do 100,000 miles.

I don't know what massive shifter issues you think there will be with putting the Subaru box in the back of a buggy. It works the correct way with first left and forward and reverse right and back. Reverse lockout is provided by the box so can be removed from your shifter mount. The shifter rod from the Subaru box comes through 2 inches to the right of where the VW shifter rod comes through. Surely not too much of a challenge to couple the two up together? Some images for you to check out :

Sun Feb 21, 2010 9:23 am

The shifter with the rod and coupling offset to the right inside the tunnel looks pretty do-able for someone who is ready to do the necessary surgery. It does look like the coupling will also be a bit higher and farther forward than with a stock type 1 nose cone. With a Type 2 you either run the shift rod above the tunnel, or mount the transaxle at a steep angle, after the frame horns are significantly clearanced. People know that going in.

With the Subaru, until its done a person doesn't know how much the chassis will have to be modified. Frankly the shift rod coupling location looks like it might interfere with the section of the tunnel where the serial numbers are stamped. That area can't be cut for obvious reasons.

The shift action with the Subaru trans might be better than the notoriously sloppy Type 2 VW. Still the only way to know is see it done.
I'm genuinely looking forward to seeing you get it done and proving the feasibility and advantages.