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Previous Next Up Topic Engines / Subbug - Subaru Power / Kennedy Adapter Troubles (32537 hits)
By @Jeff GS Date 2007-01-15 16:31
Just wanted to post some observations as I began trial fitting my KEP adapter kit.  My application might be a little different than most - attaching a Subaru engine to a Porsche (914) Transaxle - but what I ran up against might help others with their own projects.

My engine is still on the stand, awaiting the next trial fitting into the chassis.  That'll happen this Spring, as soon as I get more of the chassis mods completed.  But back to the KEP kit... I have the tranxaxle mocked up in the chassis, so wanted to test-fit the adapter plate to the trans.

My adapter plate was delivered with the (4) transaxle mounting studs already mounted in place.  It was a simple matter to slide these into the trans face and mate the adapter to trans - BUT I found the adapter wouldn't fully seat against the trans bellhousing!  It seemed the centering ring on the adapter plate wasn't mating up properly with the stepped counterbore in the bellhousing.  My old trans had a lot of crud/oxidation in this area, so I spent quite a bit of time cleaning it up - but it still wouldn't mate up.  Then I got out the dremel and performed some light "clearancing" in the spots that seemed to be interfering.  I didn't want to go too far as I'm sure this fit is critical for proper centering of trans to engine - but after several tries including some gentle "persuasion" with a soft faced hammer - still NO GO.

This just wasn't making any sense, and the studs installed on the adapter weren't helping matters.  I decided I needed to remove the studs and see if the centering ring on the adapter was actually made to the right diameter - with thoughts of a possible return of parts to Kennedy in mind....

Upon closer inspection I also wasn't very happy about how the studs were installed into the adapter plate - looked like some ham-fisted Kennedy employee liberally used a set of vice-grips on the stud shanks to screw and tighten the studs into the adapter....

I double-nutted and removed the studs, and immediately begin seeing a trend and possible cause of the problems - the studs were bent!  3 of the 4 had some amount of runout as I was unscrewing them.  Once out, I also noted some slight "raising" of the metal around the stud holes - which certainly wouldn't allow the trans to mate properly with the plate.   Spent some time deburring and flat-filing these areas, as well as adding a slight chafer around the centering ring (which had sharp as-machined edges).

Back out to the trans and the adapter plate fitted up perfectly to the trans, now fully seating with a nice snug fit.  I also eyeballed the mounting holes and these all looked to align properly between plate and trans.  So it looks like the problem was definitely the studs.

I've read these are supposed to be class 8.8 (equivalent to class 5) studs.  I've also read about these sometimes breaking on Vanagon conversions.  The stress risers and potential fractures from the vice-grip "mutilation" certainly wouldn't help in this regard!

SO studs will be getting replaced - but ever try to find good grade metric double ended studs??!!  I finally found some black-oxide coated class-5 equivalent double ended studs in the McMaster Carr catalog, not exactly the same lengths as the Kennedy supplied parts, but close enough.  I may actually thread these through the adapter plate and into the engine side of the plate and use a back-up jam nut on that side - looks like the engine flywheel cavity has plenty of room for this.

I'll update as the project moves forward.

A word to the wise - check those studs!

By Ross C 356 Date 2007-01-16 18:47
Sorry to hear of the problems.  I purchased the same KEP kit for a 914 to a Subaru several years ago and was very impressed that everything fit perfect, I don't think the studs were installed in mine when it was shipped.  I would check with KEP and have them send you a new set of studs, no charge.

What is the 914 tranny and Subaru going in?
By @Jeff GS Date 2007-01-17 01:48 Edited 2007-01-17 12:32
Hi Ross,

Going into a mid-engine Deserter GS.  About those studs - I really didn't like the look of 'em anyway, kind'a had that cheap harware store grade look about them - and they were probably bent from new.
Just got my nice replacement studs today - the black oxide finish certainly gives them a more durable "commercial grade" look!  They roll perfectly true on my surface plate too!

The only other thing I'm a little disappointed about the KEP kit is the flywheel.  I opted to get the 9" set-up, thinking they had a nice custom flywheel for this.  Instead, it is a "built up" design from several pieces/plates/rings of steel welded together - and weighs in a hefty 20 lbs.  I asked Kennedy if they could lighten it - their response was no.  I figured the 9" size would give me all the holding power I'd ever need, along with an easier clutch pedal.  In hindsight I think it just cost more for capability I don't need and slightly slower revs.  I do think much of the mass is near the center with the big hub - but it's still a heavy sucker!  At least it should "load" the turbo more, maybe giving earlier boost!

By Ross C 356 Date 2007-01-17 14:30

Do you have a picture of the flywheel?  When I did my 914 tranny/ Subaru I went with the 914 flywheel, pressure plate and clutch disc.  I sent in the 914 flywheel as a core and they welded a thick boss to space it out and re-surfaced it.  The boss was thick and heavy.

There is a 914 in a local junk yard and I have been thinking of picking up the Transmission and rear trailing arms for a future mid engine project.  The only thing that is holding me back is it is the early transmission with the rear end cover shift that requires the linkage in the shift rod.

Are there any pictures of the Deserter GS project on the forum?
By @Jeff GS Date 2007-01-17 23:05 Edited 2007-01-28 16:19
Hey Ross,

Didn't have any flywheel pics - but good as time as any to take some!
Give me a chance to try out my photobucket album.  Here goes:
First pics of the new adapter studs:

You can see the new studs are slightly longer, I can either cut one end shorter, or add a locking nut on the engine side (or both on the longer "starter" stud).

Next - the ubiquitous Adapter Plate:

The Flywheel - again this is the 9" clutch set-up:

and rear view - pretty good look at the construction technique:

Lastly - what it's getting attached to!

Lets see if this works...
By @Jeff GS Date 2007-07-26 11:47
Just wanted to provide a little update on those replacement adapter plate studs.  I ended up cutting them off on one end to match the length of the Kennedy supplied studs.  Then installed them in the adapter plate with lock-tite.  After that assembly was a breeze - everything fit perfectly.

I did have one unanticipated problem with the overall adapter fit though, no fault of Kennedy or anything.  The adapter and studs have to be installed first on the engine (then the flywheel), then engine fitted into the car.  Those long studs sticking out the back of the engine really complicated the installation in my mid-engine chassis!  I found I'll have to un-hook the trans and pull it back some to allow dropping the engine down into the car - a little more hassle to R&R the engine.

By Paul Moran (DBA Architect) Date 2007-07-26 15:18
Hi Jeff - Sounds like your making good progress if your fitting the engine and trans both in the chassis. 

The Hecker flywheel that arrived was a one piece 200mm unit.  Now I wish I had weighed it before installation...  All the studs arrived in a bag, so no "poorly installed or bent" studs to deal with.  I also wish I had test fit the adapter to the trans, but during install with the EJ25 to a VW transaxle, I didn't see any problems.

The long studs help in mating the engine and trans, but without room like in a rear engine application, I can picture that sliding the trans out of the way would complicate matters.

Chicago, IL
EMPI Imp 1002 ('69)/Subaru EJ20 Turbo/LinkPlus ECU
By Ross C 356 Date 2007-07-27 17:32
I was reading someplace that people were breaking stud with the Kennedy adapters in VW bus applications.  In the bus they utilize the Subaru motor mounts on the engine where my engine hangs off the transmission just like a Beetle.  I have an adapter plate from Outback that looks basically the same as a Kennedy.  Should I have any concerns about breaking studs?

By @Jeff GS Date 2007-07-28 11:15
I read about that too Ross, but I believe the instances were pretty isolated.  I don't like the engine mount locations on the Subaru engine - almost right next to the bellhousing.  This causes the engine to be cantilevered more than I like.  Still, most conversion folks use those mounts for extra support and it seems to work just fine.

That's one reason I switched to the Small Car mounts, I liked supporting the engine at opposite ends.

Keep and eye on the bolts, but otherwise drive and have fun!  The buggy is looking good!  How's that cooling system working?

By @Jeff GS Date 2007-07-29 14:46
Hey guys - here's a pic of the adapter plate installed with the new studs.  Getting ready to go into the chassis for some test fitting!

Starting a new thread for the installed pics.

By charliew Date 2007-07-30 13:38
Jeff Hi, If you get a chance could you post a picture of the small car motor mount? I would reall like some support at the pully end of the motor.Thanks,

By Jodi B 736 Date 2008-01-11 21:54
The Studs on KEP Adapters use to be installed on the adapter about 2 years ago, by double nutting them, never with vise grips.  We started having problems with UPS dropping the packages.  With the flywheel set inside, the studs with cardboard to protect the studs the weight of the flywheel was bending the studs and the ring gear, in some cases, was cutting thru the cardbaord and messing up the stud. (not Vise Grips)  Now we do not install the studs to prevent this problem.

The stud breakage on Subaru to Vanagon conversions is due to using the Small Car crossmember which does not cradle the engine but supports it at the back which lets it pivot and make the sutds come lose and then they break.  We have never had a stud break with our crossmember.  If the engine is supported correctly they won't come lose and break.

If your studs were damaged when you got your kit why didn't you contact KEP instead of posting complaints that don't solve your problem?  We always stand behind our product.  All KEP 9" and 8" flywheels are now 1 piece forgings and have been for 1 1/2 years, but we have never had a problem with our old style flywheels.
By @Jeff GS Date 2008-01-13 20:34
Hi Jodi,
I checked my KEP invoice - dated Jan 2006 - so it was exactly 2 years ago.  I also had another look at the studs - and the damage could be very likely as you described.  The gash marks in the studs are all on one side (on the studs that I kept) concentrated on about 1/4 the diameter of the affected studs.  I can see it could have been very possible a shifting flywheel (ring gear teeth) knocking against the studs causing the damage - though there is no obvious indication on the external box that the the package was ever dropped or even roughly handled?  The flywheel teeth show no damage that I can find.

I'm not trying to bash Kennedy as overall I'm pleased with the product.  The only thing I wish I would have looked into further was the "built-up construction of the flywheel.  At the time all the "vendors" offering the Subaru adapter kits were advertising one-piece flywheels.  It was my "assumption" many of these were coming from Kennedy.  My fault for not checking this out when I placed the order.   My only real concern is the overall weight of the flywheel - and when I contacted Kennedy about the possibility of lightening it - all I got was a "no, we don't", with no explanation or other possible options.  Still, because of the design of the flywheel and the massive center hub - I believe a significant amount of the overall weight is the inner hub, which hopefully won't affect (too much) the overall engine acceleration rate.

I have not yet installed the flywheel though - so if there are any other options to get the flywheel weight down, maytbe into the 16lb range? I'd be very interested in hearing what is available?  How much do the 1-piece flywheels weigh (for the 9" clutch package - Porsche application)?  If it's significantly lighter is there any possibility of trading in my unused "built-up" flywheel for 1-piece model?

Back to the studs - when I realized there was a problem it was well past the 90 day period where I expected any kind of warrenty might be offered.  To me, the straightforward solution was to just source my own studs - of possibly higher quality material (not that they in reality the are or are not?).  Had I realized there was damage when I opened the package at delivery - I would have definitely contacted Kennedy.  But it was much later and I figured what the hey - I'll see if I can find some studs from my own resources.  To me, no big deal.  Kennedy's later choice to not pre-install the studs was a good one!  Glad to see there is continual product improvement going on.

By John F 788 Date 2008-02-18 01:01
I also thought the KEP flywheel seemed heavy. For comparison I put a 9" KEP setup (flywheel + stage 2 pressure plate + disc) and the original Subaru setup that came off an '04 WRX on a scale, and the KEP combination was 5 lbs less. Plus, the KEP flywheel has a smaller diameter so would be easier to spin up.
By @Jeff GS Date 2008-02-18 14:10
Can you post a weight of just the flywheel - for comparison?  Is yours a built-up version like mine, or 1-piece forging?
By John F 788 Date 2008-02-20 11:49
Jeff, mine is a 1-pce forging. It weighs 20 lbs.
By @Jeff GS Date 2008-02-20 22:32
Thanks John - at least it sounds like we're going a little lighter than stock!  My thought was the Kennedy was going to be heavier, you're weight measurements do give me some piece of mind!

By Paul Moran (DBA Architect) Date 2008-02-21 03:49
Here are the details on the Hecker Machine Subaru adapters:

Bolts/Studs: 2 lbs (shipped in a bag, not on the adapter)
Flywheel: 19.25 lbs
Adapter: 5 lbs

I'm trying to find out from Dan how the flywheel is made.  Paul...
Chicago, IL
EMPI Imp 1002 ('69)/Subaru EJ20 Turbo/LinkPlus ECU
By ian h 817 Date 2008-03-09 14:56
can you tell me what that is you have done with the idle bypass valve please
stock legacy turbo in a beetle 11.23@127mph qtr mile
By @Jeff GS Date 2008-03-09 22:03 Edited 2008-03-09 22:10
Hi Ian - I'm guessing you're referring to my engine pics in the above posts?  I've shelved the original "bulky" idle bypass valve in favor of a smaller stepper motor controlled valve.  Still not sure where I'm going to mount it, but somewhere close to the block to keep heat close by and prevent icing.  Where the original valve was I just made a block-off plate and installed a fitting that'll go to the new valve.  The new IAC valve will be comtrolled by my megasquirt ECU.

Here's the valve I'm going to try using:
Previous Next Up Topic Engines / Subbug - Subaru Power / Kennedy Adapter Troubles (32537 hits)

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