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In response to Ryan in NorCal's current predicament with his frame horns how hard are Kafer Bars and Mendeola's Stiffy system to install in our cars? Who should have one? And how much of an improvement do they make? Which system is the best?

If you're not living life on the edge, you're taking up too much space!

 

 

 

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Gene Berg once said that he didn't think any additional engine support was necessary in his stock '67 beetle but after several thousand miles of "spirited" driving he noticed that the engine tin no longer lined up with the engine compartment and the frame horns were bent. He straightened the frame horns, mounted a Gene Berg traction bar and had no further problems.

My point of mentioning the above is that any VW based car that's driven harder than the Elves at Wolfsburg intended needs additional trans/engine support. Although the Berg traction bar is popular with the Beetle crowd, with Speedsters it's harder to do as the sole means of support because the rear of a Speedster body is different and the traction bar itself won't clear a Sidewinder exhaust. A kafer bar that ties the shock towers and frame horns together is (I think) pretty well essential in our cars (along with a mid mount) to stop rear suspension hop (which breaks transaxles very quickly!). A rear engine support like a couple of the guys here have made would also be a smart idea; Stan I think has done it and someone else made his out of aluminum (with lightening holes, engine turning and everything! sorry but I can't remember who it was (Bruce maybe?); it was very well done though). As to which kafer bar- the engineering of every one made that you can buy has been picked apart by competitors but I think for 95 or 98% of our cars any one will stiffen the back end up enough to do the trick. Something as simple as welding a bar between the shock mounts and (if your car is irs and you don't have to worry about the axles and tubes on removal and installation) bars welded inplace between the top shock mounts and frame horns would work, along with the previously mentioned mid mount and engine support.

Search kafer+bar on the Performance/Engine/Transmissions forum on the Samba and you'll get plenty of reading...Al

The honest answer, Bob,   is - "It Depends".....

There are several different versions of a Kafer bar out there from inexpensive (I hesitate to use the term; "cheap") to wicked expensive and then there's the Mendeola "Stiffy" system (I love that name, too) which I'll cover later.

Before you go out researching what's out there, the first questions to ask are; 

1.  What level of torque does my engine generate?  Anything under a 2,110 probably won't benefit from either form of brace.

2.  How hard do I drive it?  Do I hammer it all the time or am I a "Sunday Driver", sedately puttering about the back roads and watching the clouds?

3.  Do I spend a lot of time on winding back roads where the speed limits can be higher and I have my foot in it a lot doing hard acceleration out of the corners?

4.  Do I enjoy "drag racing" other cars out of stoplights?

5.  Do I need one?

The Kafer brace (sometimes called a "Truss Bar") is designed to provide a triangulated brace system to hold the ends of the frame horns (the arms that hold up your transaxle and engine) in place during hard acceleration.  Common indicators of the need for this is shuddering or wheel hop under hard acceleration (if you have the power) and destroying the front transaxle rubber mount in a season or less.  As an aside, the lowly, wimpy VW had but one front transaxle mount, while it's race-bred sibling, the 356, had two.  What's that tell ya?

So the Kafer brace forms a dual triangulated bracing system between the top of the rear shock towers (with a big bar between them to hold them in place) and the ends of the frame horns where the transaxle bolts up.  Stiffens things up nicely, but if you already have an anti-sway bar back there (for IRS) or a Camber Compensator you might not notice much of an improvement, if any, in the seat of your pants.

So....They are especially helpful on cars with a large amount of torque, like over 120 ft. lbs. or over 120 hp.  They keep the rear wheels on the ground when accelerating by holding the frame horns still and preventing a wave-action from taking place (wheel hop).  This is a big deal with sand rails and dune buggies and the Truss Brace is very effective in those applications.  You have to have a LOT of horsepower, a very heavy foot and like to do some very fast launches to see a need for a Truss brace in a Speedster, although I've seen a few at Carlisle with gobs of power and serious wheel hop on launches.  They all needed a Truss Brace.  Remember that the other indicator is shredded forward transaxle rubber mounts so if you shred one every other year or so you're probably a candidate for a Kafer brace (or maybe a mid-mount on the transaxle).  The (tube) sizes range from 3/4" (softest, but still pretty stiff) up to 1-1/4" (stiffest) 

A truss/Kafer brace will usually not improve road handling in a straight line or on curves - THAT is the job of an anti-sway bar to hold your car flat.  The Truss/Kafer brace is there to prevent your engine/transaxle from bouncing up and down or torquing in an arc on a launch under high-horsepower stress.

Now......The Mendeola "Stiffy":  Awesome piece of engineering work, there.  For those rare installations with, say, over 200hp and over 200 ft. lbs. of torque (that's one hell of a lot of power in a Speedster), where the tires really bite and the launch is solid, the engine/transaxle is going to try to twist the front of the transaxle up while the rear of the engine is going to try to go down - think massive tail-squat on take-off.  You want to minimize that as much as possible and the best way is with a Kafer/Truss brace, but there is SO MUCH POWER being generated that the Kafer brace needs a little more help, so the Mendeola guys added a couple more anchor points on the torsion bar housing to really stiffen things up.  Put one of those in there and it'll be like the Rock of Gibralter - nothin's going no-where.

Full disclosure:  I have never seen a Mendeola in the flesh, but I understand what they're doing with it.  Not sure where they attach the forward mounts on a swing-arm but they say it's 100% bolt-in, so there you go.  On an IRS, the forward mount is at the diagonal arm mount and just uses a longer bolt.  Mendeola's supplied mounting plates are all 1/4" thick steel - really beefy.  My Bugpack plates were 3/16" as a comparison.

I installed my Bugpack Kafer Brace in about an hour, with the engine and transaxle in the car, with very little cussing or blood.  I had to fabricate transaxle saddle mounting plates because of interference with stuff on my car, but that was no big deal and not their fault.  I made them big and adjustable at the same time, but found I didn't need that adjustability, so there.

Guess that's it.  Stan's CSP version is the best I've seen, but expensive in comparison - It also uses heavier tubing and really beefy Heim joint ends.  My Bugpack is something like 3/4" or 7/8" tubing, also with Heim joints so it is easily adjusted to preload the frame horns up or down after the bar is installed, as are any of them.

Hope this helps.  gn

Last edited by Gordon Nichols

Thanks Gordo.

Here's the answers:

1.  What level of torque does my engine generate?  Anything under a 2,110 probably won't benefit from either form of brace. Pretty stock 1915 with about 105 hp. (est)

2.  How hard do I drive it?  Do I hammer it all the time or am I a "Sunday Driver", sedately puttering about the back roads and watching the clouds?  I drive it pretty hard when I'm out with Teby.

3.  Do I spend a lot of time on winding back roads where the speed limits can be higher and I have my foot in it a lot doing hard acceleration out of the corners?  I spend a lot of time on winding roads and I don't take it too easy. In the corner at speed and I hammer it coming out.

4.  Do I enjoy "drag racing" other cars out of stoplights? I wouldn't want to make too much of a confession on a public forum but I may have jumped a few lights on green.

5.  Do I need one?  I didn't think I did but now that I've seen Ryan's I'm thinking it couldn't hurt.

Wow, Gordon you've covered it all! (my brain is full, Mr. Nichols!

A couple things- I've scrambled a transaxle (broken spider gears) in my stock '72 bug with stock 1600 (maybe a header?)- big burnout in the rain, big wheel hop and oops! what's that noise now? And yes, it was me quite a bit younger- 40 years ago and yes, "watch this. Hold my beer!" (or something very similar) were my words immediately prior to proving my idiocy. This and Berg's comment in my post above leaves no doubt in my wee pea brain that every VW based car, whether powered by a stock engine or something larger, even if driven in a spirited manner only very occasionally, needs some kind of frame horn stabilization so there's no movement or flex when even a little power is applied. And btw- any time you blow up spider gears or a r&p you could have destroyed the trans case (you've spread the mainshaft and pinion bearing saddles just enough that things won't stay in alignment) and you're looking for another core since putting it back together with that case won't last very long, so it can get to be a rather expensive repair! Refer to earlier in this very paragraph to find out how I know this...

2nd thing- when setting up a kafer or truss bar there is no need to "pre-load" things this or that way. Set it up so things are tight but in alignment. If it's built properly, once things are cinched down (or welded), nothing's going to move (that is the point of the exercise, after all). Al

PS- Having just read your post above, Robert, I think your car could benefit from a kafer/truss bar. Does it have a mid mount?

Last edited by ALB

Ahhhhh.......Jake!  The Ghost of Speedsters Past!"  (Sorry, couldn't resist...)  He always has great reasons for choosing the parts he uses - And Product Quality usually tops that list!

Well, Jack, I might add that to my car manual, too.  It's getting pretty big these days - well over 300 pages!  Good thing I did it as a hyperlinked Doc so I can find stuff in it!

I could debate the advantages/disadvantages of preloading a Truss Brace over beer but be warned....I don't drink cheap beer.  Strange Fellows or Four winds or nothing....

It all depends on what'cha wanna do with the car and how stiff you wanna make it and exactly when you want that stiffness to work (and how), but it'll cost you a Strange Fellows Porter to get more outa me.  

Bob!  Buy a Kafer brace!  Get Teby to install it (or at least bring the beer).   It's a LOT easier to do the installation up on a lift, so find a beer-drinking lift with a friend and have at it.  A lift that supports the frame/pan is better as you'll want to pull the rear wheels for access to the top of the shock towers.  Don't be like "Stupid Gordon" and try to do it lying on a creeper under the car - that sucks.  With a lift, take you maybe an hour or two and you're done.  Good rainy afternoon project, if it ever rains out there.  

Given your outline of how you drive, you probably need one.  Ryan, too!

Last edited by Gordon Nichols

That's funny, Gordon.  I may have gotten the very last Type IV installed in a Speedster---now the usual upgrade from the old VW Bug engine is Suby power.  I feel like the last guy shot in WWII!   

I do have to say that I have over 30,000 miles on my Raby TypeIV  (50k on the car) and the IV has been absolutely bulletproof.  I hesitate to say such---knock on wood and all that but I know I could fill the tank and point it to the left coast and get there as trouble free as in my Genesis.  

Still---a coupe with a Raby Suby is the one thing I might enjoy.  

 

 

Gordon Nichols posted:

 

  ...I had to fabricate transaxle saddle mounting plates because of interference with stuff on my car, but that was no big deal and not their fault.  I made them big and adjustable at the same time, but found I didn't need that adjustability, so there...

 

Again, very informative post, Gordon. Any pics of your custom mounting plates?

Jack Crosby posted:

That's funny, Gordon.  I may have gotten the very last Type IV installed in a Speedster---now the usual upgrade from the old VW Bug engine is Suby power.  I feel like the last guy shot in WWII!   

I do have to say that I have over 30,000 miles on my Raby TypeIV  (50k on the car) and the IV has been absolutely bulletproof.  I hesitate to say such---knock on wood and all that but I know I could fill the tank and point it to the left coast and get there as trouble free as in my Genesis.  

Still---a coupe with a Raby Suby is the one thing I might enjoy.  

 

A Type IV...umm, for sure it would be a nice engine ... cost wise going forward a Subie does seem to make sense, but it is a different platform and a new learning curve.

 

Robert M posted:

@ALB

PS- Having just read your post above, Robert, I think your car could benefit from a kafer/truss bar. Does it have a mid mount?

Any suggestions for a mid-mount, including a link? I thought about one of those a while back while reading about Bruce's custom made one with the holes and swirl marks.

http://vwparts.aircooled.net/F...termediate-mount.htm

This one seems to get a lot of positive praise.

Will Hesch posted:

Robert, that's for the front of the transaxle and wouldn't support the rear of the transaxle and engine and frame-horns which are after-all, the weak-link in this system with all of the weight and torque they support.

Al, aka Yoda, was suggesting both the Kafer Bar/truss system and a mid-mount for total support if I read him correctly. Under hard acceleration the front of the transmission lifts causing wear on the nosecone. 

Robert:   I don’t wish to contradict Will, but what your link shows is a mid-mount.  To Will’s point, it actually mounts on the forward half of the transaxle case, not the nose, and is therefore called a “mid-mount”.   Technically, it mounts where the tranny nose cone attaches to the transaxle case.  Under hard acceleration, the nose of the transaxle tries to move upward while the back (engine) end tries to move downward, pivoting around the axles as a pivot point.  That brace attaches to the underside of the transaxle case to existing tranny case studs (you may need longer studs in the case) and the outrigger pads snub up against the bottom of the frame horns, preventing the transaxle nose from moving up.  Ideally, you leave 1/16” or less gap between the red urethane bumpers and the bottom of the frame horns so they don’t rattle.  Also, under acceleration the urethane bumpers make contact with the frame horns and can transmit a bit more noise into the frame/car than rubber bumpers might.  

I installed a Gene Berg mid-mount transaxle support.  It is really rugged.....If Al had one he would drill it full of holes, I’m sure, for that “Steam Punk” look, but I left it alone and just welded in the mounting tabs (OK, so my SON welded it in so they wouldn’t fall out), painted the welds and bolted things up.  It’s the Berg GB 643 in this link:

http://www.geneberg.com/cat.php?cPath=11_351

That is one of several available at different price points.  I am not a fan of the bolted-on mounting tabs on some, but whichever you get, make sure it is one that can be preloaded (snugged up tightly) so that nothing can rattle.

So, to ALB’s point, if you’re going to the trouble of installing a Kafer Brace (who the heck IS “Kafer”, anywho?) you should also install a good mid-mount on the tranny, too.  Hey!  It’s only money and it can save your transaxle case, too.  The Kafer brace keeps the engine/transaxle from moving up and down on the ends of the frame horns, while the mid-mount prevents the engine/transaxle from pivoting around the axles, both under hard acceleration.  Both work together to make the rear of the car much stiffer and prevent things from breaking.  Same thing Will said, just with a lot more words.  (I know.....it’s a curse.)

Now, on installing a Kafer Brace with the engine still in, part of the installation is removing those big, honkin’ bolts that hold the engine/transaxle to the saddle brace between the frame horns so that you can install the lower mounting tabs for the Kafer brace.  THAT is the big deal here.  If the engine/tranny bolts are removed the whole thing will try to fall to the floor.

All you need do is support the engine/transaxle with a floor jack or transmission jack (my local Autozone actually rents tranny jacks) so that you can keep them in place while the bolts are removed, the attach plates installed and then the bolts replaced.  That’s it.

Now, is it easier to install a truss brace with the engine out of the car?  Sure.  You can sit up in the engine bay and just install the brace.  Do you NEED to remove the engine to install a brace?  Nope.

Last edited by Gordon Nichols

Hi David.....The rubber bushings at the ends of my traction bar came from Summit Racing. They are pretty hard rubber and I use four of them. One on the top of the bar and one on the bottom of the bar tips. I used a 7" length of 3/8" stainless all thread on each bar tip which goes up through the 2" square tube on each side of the engine compartment. Two nuts secure it to the 2" square tube (fender washers of course where they come in contact with the rubber bushings). The rubber bushings also have a protrusion that isolates the 3/8" rod from having metal to metal contact with the aluminum tabs on the ends of the torsion bar. This insulates/isolates the bar from transferring noise  to the body of the car.  I don't have any detailed photos of that exactly bur here's the last photo I have. I hope this helps......Bruce

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I used the CSP unit also and built my own mid mount, basically copied the GB one but made from aluminium earlier this year. Made a massive difference.

Didn’t put any preload on the brace bar and noticed straight away going over speed humps (yes we have them in the UK) that something sounded loose. Added slight pre load and it cured it straight away. Figured what was causing it was the slight slop in the holes, which the bolts went through on each mounting moving side to side has the chassis twisted going over the speed bump. 

Also noticed it’s  put more vibration through the gear lever also but that doesn’t bother me. 

@Stan Galat a few years back I sought out and purchased an RCA New Vista Victrola HiFi console from 1965. I love it, but a number of folks that come over tell me the same thing: I need to swap out all the old outdated awful sounding equipment and install new modern sound equipment inside. 

But I already own a new modern sound system. I wanted this console specifically to listen to music the way it was heard in the 1960s.

“ If you wanna be happy for the rest of your life
Never make a pretty woman your wife
So from my personal point of view
Get an ugly girl to marry you“ -Jimmy Soul

—Kevin

 

Last edited by Kevin - Bay Area
Will Hesch posted:

I did not know better so I guess ignorance was my excuse...

my mom said my excuses were lame...guess they still are...

Will,

You're fine. IRS becomes a thing when you are carving up the twisties at about 9/10 or so. 550 Spyder's have swing-axles, and most of them will leave pretty much any speedster for dead in the mountains. Swing-axles are stronger in a drag-race application, which explains why Cory Drake converted his car from IRS to swing when he turned his car into an erector set.

Pretty much all Vintage Speedsters are swing. All Becks have been up until this point. All Intermeccanicas are IRS since the move to Vancouver in the 80s. JPS will build on an IRS pan, but he'll put 4-1/2" rims on it if he does. 

It's a lot like IDFs and Dellortos. The Dells are functionally superior, but the IDFs can be made to work perfectly well.

I wouldn't sweat the swing axle, unless you experience snap-oversteer on more than one occasion. 

 

Kevin,

I'm going to guess you didn't take that advice when searching for a mate. If you did, I'd like to hear what Mrs. Kevin thinks about that.

I suppose I understand wanting technology as close to original as possible (specifically looking for a swing-axle car, vs IRS), as I am an air-cooled fanatic in the face of the clear superiority of a Subaru platform. I guess I draw the line in a different place-- I want to be able to run at 9/10 or faster, and the IRS puts that limit further out there.

I wonder if you were looking for drum brakes as well?

Last edited by Stan Galat

 

Ah right - the first snap oversteer episode in a swing axle VS.

I still remember the crisp, fall air, the terrorized looks of nearby pedestrians, the color of the Lotus Elise I was chasing.

That was the day I learned the car's cornering limits - or at least my cornering limits. If you survive, it can be an enriching experience - an opportunity for emotional growth.

So, why do so many of us put up with this? I think I was like a lot of first time VS buyers. First, I didn't realize IRS was an option. I guess they'll install it if you insist. But I also didn't know enough to go against the flow.

VS has sold a bazillion swing axle cars, so that must be good enough, no? And the whole point was going old school, too. Let's get a full taste of it. And folklore tells us the 356 was a great handling car, so who am I to question that?

That said, I didn't get this car for its lap times at Laguna Seca. Most of the time, my wife is in the right seat and she emits an audible warning when cornering speeds in any vehicle reach about 6/10ths.

And in time, you do discover it can be fun getting close to but not quite all the way up to that point where oversteer snaps. You can learn to slide it a little to help you through.

There must be lots of other lame excuses for swing axles, but I can't think of them right now.

 

Last edited by Sacto Mitch

"That said, I didn't get this car for its lap times at Laguna Seca. Most of the time, my wife is in the right seat and she emits an audible warning when cornering speeds in any vehicle reach about 6/10ths."

***** Pussycats in the front seat always squeel  

I do find the logic behind keeping the swing axel a bit lacking.  I mean getting IRS and a custom rear set of wheels with Positive offset should be a  no brainer.  

Last edited by IaM-Ray

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