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Fri Oct 02, 2009 12:53 pm

It occurred to me that I asked my previous question from the wrong end, so . . .

Does anyone drive a dune buggy that handles like a go kart? Anyone own one and just LOVES the way that it handles?

If you do, PLEASE post the details on what you did to make it handle so well. Please be as specific as possible since I want my car to handle just as well.

Thanks ! ! ! !

TC

Fri Oct 02, 2009 1:26 pm

Mine is pretty good all stock except having wider tires in the back may help some, but its fine as long as Im not taking super sharp turns over 50/60. This thread below covers handling.

http://www.thesamba.com/vw/forum/viewtopic.php?t=340486&highlight=handling

Fri Oct 02, 2009 3:58 pm

Mine has superb handling, although it is a touch on the stiff side when it's empty. Here are the specs:

Ball joint front end with stock torsion leaves

IRS rear end (long torsion bars) with 24mm bars instead of the stock 22mm ones

Fox shocks all the way around

The last item is the main reason for the excellent handling. I have had the shocks revalved more times than I can remember. You can tune them to fit your needs exactly, and I have done just that. It took a lot of time, but the results were well worth it.

Torsions are stock or heavier than stock in order to handle the extra weight I add on while camping. That's why it's a bit stiff when the car is empty. It could stand to be a little stiffer when it's fully loaded, so I think it's a good compromise.

Lee

P.S. The other secret to having a good handling buggy is to make sure all components are within spec and then have a four wheel alignment done by someone who knows VWs.

Fri Oct 02, 2009 4:12 pm

Mine buggy handles better and actually rides better on country roads than my 04 Chevy truck ( did I mention I hate that truck) ..

MY street car is swing axle and rear is dropped 2 splines (I think) and rubber bumper (jounce stop) on rear is about 1/2 to 3/4 inch off stop...

Front is lower beam with AVIS adjuster about half way down and all the small leaves out of torsion stack (only large leave remain)... KYB gas shocks all around, new steering damper and and caster shims under lower beam... And steering box with NO PLAY in it.......

3/4 inch sway bars front and rear....

At 60 mph on freeway conditions you can let go of wheel and it tracks straight......... Key here is to get proper 4 wheel alignment... Also big tires with low air pressure.....

Dale

Fri Oct 02, 2009 4:42 pm

I drive my Manx on the interstates at 70 MPH + and it does fine , its stable and never have problems with lane changes or wind from trucks passing except for the side curtains popping loose!
Its a short wheelbase car, link pin beam with a "cut and twist" on the top tube, and an adjuster on the lower tube. Also have caster shims behind the lower tube. The rear has been converted to IRS, and the torsions are set at 12 1/2 degrees.

Fri Oct 02, 2009 5:15 pm

I own 3 of them.
Kyote/ 1600dp 65chasis-king/link, swing axle
Manx/ 1800 T4 68chassis-ball joint ,swing axle
Manx/ 2.0 T4 injected/74chassis- ball joint ,swing axle

All of them handle like an overpowered gocart, Like riding on rails, Smooth ride and excellent handling.

From a post I just answered.

Quote: TC/TeamEvil wrote:
"After the " transformation" I can honestly say the thing is a handling machine!"

With regards to the front end specifically, could I ask what you did to accomplish the transformation in handling? Specifics PLEASE, as I'm currently in the same boat as you were before. I know that you now have a custom frame, but you must have re-worked the front suspension to achieve the handling improvements that you mentioned. THAT'S where I need the most help. The car is frightening as it is now. The front suspension is harsh and skittish in turns of nearly any speed. If you could lay it out for me, step-by-step. Part-for-part, I'll be your best friend FOREVER, I REALLY need some help and you sound like you've already accomplished just what I'm hoping to do.

Thanks ! ! ! !

TC

Just make sure all joints/kingpins/linkpins are free to move in all directions with no binding. Make sure there is NO PLAY in any of the suspension and steering parts, Make sure your steering damper is in good condition as are the shocks. Then go and pay for a proper 4 wheel alignment.If you are running tires that are much wider than stock with rims that set the entire rim out farther than stock, INCREASE your CASTER. Set your tire pressure around 15psi.

Fri Oct 02, 2009 7:11 pm

just like a Go-Kart. a few weeks ago i took a turn on 3 wheels.

Fri Oct 02, 2009 7:45 pm

After building and driving two short buggies, I can say my long body handles and rides much better in every aspect the only exception is the turning radius is not as tight as the shorty's.

Fri Oct 02, 2009 8:37 pm

I'm no expert but I have built numerous front beams so here's my 2 bits;

If you are after handling, you need the moving parts of the suspension working as smooth as possible. Check the bearing in the end of the beam tubes. I've seen countless ones that were hammered to death, bent, rusted needles, etc. These have to be clean and smoooooooth in action.

DO NOT use the eurathane bushings designed to replace the factory needle bearings or inner bushings. These have WAY to much stiction for such a light car. In fact, that sticition is why people running narrowed beams without shock towers WANT the bushings. They tend to act like "friction shocks" and keep the front end from bouncing.

As for torsion bars in buggies here's what I think and have observed;
Torsion adjusters adjust the starting point and thus ride height of the front end. They DO NOT alter the spring rate or spring progression at all. Think of it like this... If you had a "regular" production style A arm front end with progressive rate coil springs, BUT the upper spring perch (mount) was adjustable, it'd be like one of our beams with adjusters. You would be able to tune ride height by altering the height of the perch and thus the point when the springs begin to carry the load of the front ends. The spring rate remains unaltered.

Now suppose you pulled the 454 big block out and transplanted in an aluminum block 2.0, 4 banger... Don't ask why. Maybe you're a whacked out treehugging gear head with an internal personality conflict... Anyway, now the front end is gonna sit as high as 60's era Gasser. Sort of like our buggies with the Bug body removed but more pronounced. You could adjust your spring perchs to lower the front down but the springs are still gonna be WAY to stiff. As the suspension starts to compress the springs (like hitting a bump in the road) will rapidly start absorbing mechanical energy. Previously the AMOUNT of energy they had to absorb was quit high due to the weight of the big block so the springs were quit large and robust. With the "new" motor's decreased weight, there is less energy to deal with. Now the spring starts to compress and within fractions of an inch, the resistance of the spring equalizes with the energy from the bouncing car. The result being that the shock absorbers (that need stroke length to convert mechanical energy into heat energy and dissapate it in order to smooth the ride) don't get a chance to move enough to work much. The solution here is to put lighter weight springs in the front end. The light weight springs will have to compress more (during bumps etc) to reach equalibrium. This "compress more" means longer suspension movement and thus the shocks get to do their job.

The same is true for torsion bar front ends. I've seen COUNTLESS buggies at shows with the front suspensions all the way up (no droop at all) and the ball joints binding or the link pin suspension arms against the bump stops. I've also ridden in buggies with adjusters that sat lower (not slammed) but still rode stiff as all hell. As soon as the suspension starts to move it, the opposing energy forces equalize before the shocks do anything to speak of. There's just not enough inertia to the front end to compress the suspension.

On my projects and a few buddies buggies we've reduced the torsion stacks in the front beams and seen tremendous improvements in ride quality and suspension movement. Also let me state these are all street buggies with no offroad use planned. We didn't go run any skid pad tests or lap times at the local track, but the change was quit obvious. Once properly reduced, the front ends would sit more "relaxed" with some slack and not all the way up. You could also push down on the front end of the buggy and actually move the suspension. This wasn't even possible before hand.

As for shocks and such that'll depend on driving style and your tastes I think. If you start messing with sway bars be carefull and conservative. Do your testing in a controlled area away from other motorists.

Good luck and let us know what you figure out.

Mon Oct 05, 2009 7:04 pm

Mine is very close to the already mentioned above.

BJ / IRS

Adjusters front, lowered about 2 inches, all stock leaves.
Rear down one index on inside.
Rear gas KYB's, front oil shocks.

But here is where I differed. I put in caster shims under the lower front beam tube to alter the caster for the better.

Good, tight new parts on tie rods, BJ's, bearings, shocks. Basically a suspension tune up parts list.

Mon Oct 05, 2009 7:51 pm

I like the way mine rides and handles. It is street use only.

I have a '59 pan, link pin axle, stock torsion bars with all the leaves in but have height adjusters on both tubes. New king pins, all other joints & steering linkage is not new but in good shape.

I try for close to stock height both front and rear.

Tire pressure is important for both ride and handling. I have about 12 psi front & 18 rear. Tires are 195-14 front & 205-14 rear on Chevy wheels with adapters. Wider tires might look better on the rear but I don't think they would improve ride or handling (might even make it worse).

I have two caster shims behind the lower beam. Adding the caster shims made a significant improvement. It tracks well with minimal tendency to do annoying things like follow ruts or get "squirrely" on loose gravel.

Ride is a bit choppy because it is so short but the low tire pressure does soften the ride....so much so that it doesn't "rumble" on road edge rumble strips.

Shocks are well broken in stock beetle. They still work but are not too hard.

I have thought about adding a front sway bar and/or a 'camber compensator' at the rear but don't really see the need.

Mon Oct 05, 2009 11:26 pm

Lo Cash John wrote: On my projects and a few buddies buggies we've reduced the torsion stacks in the front beams and seen tremendous improvements in ride quality and suspension movement.

How do you perform this job? Can you enlighten us? I think my buggy needs this treatment as I cannot depress the front end at all when the buggy is parked.

Tue Oct 06, 2009 5:47 am

Mine is on a 63 pan - love the way it feels. Runing 205/55 15 and 295/50 15s. Rear springs have been dropped slightly so the tires sit flat. KYB gas adjust in rear, KYB G2R up front. Front was rebuilt, so it's not sloppy. Not sure on tire pressure without running to the garage to check my logbook, but as mentioned, it's real important. I love tearing around windy mountain roads with it.

My winter beater is an 07 Subaru WRX, which is no slouch in the handling department. The buggy will almost keep up with it, but you do have to work a lot harder, which is half the fun . :D

Tue Oct 06, 2009 6:41 am

Firebelly wrote: Lo Cash John wrote: On my projects and a few buddies buggies we've reduced the torsion stacks in the front beams and seen tremendous improvements in ride quality and suspension movement.

How do you perform this job? Can you enlighten us? I think my buggy needs this treatment as I cannot depress the front end at all when the buggy is parked.

Usual process is to remove BJ or Link Pin assemblies (depending on vintage of front end) pull grub screws on trailing arms and remove arms, then loosen center locking grub screw.... Reach in with pliers and grab smaller leaves (half width), should be 6 in each stack (or maybe its just 4,might depend on front end) on outside of stack... Remove up to all 6 (half leaves - Leave all full leaves in place) ) and then retighten center locking grub screw, reinstall trailing arms, tighten grub screws, reassemble BJ or Link Pins....

Dale

Tue Oct 06, 2009 8:09 am

If you're going to remove leaves you have to cut sections from them and reattach the section at each end and the center so the the grub screw dimples are in the same location and the stack remains square to fill the square holes in the trailing arm and the center beam anchor.

2" to 3" of each leaf is adeqaute. They need to be clamped on the stack and either tack welded or "JB Welded" in place. Welds need to be dressed down so the stack fits through the square holes.

Tue Oct 06, 2009 8:11 am

Correct me if I'm wrong, but, isn't that only if you do it on a link pin beam? I thought you can remove 2 small leaves in each tube on a Ball joint beam without a problem?

Liek I said, correct me if I'm wrong. It;s only what I've read. I've never done it, But, I would like to know for sure!

Thanks!

Tue Oct 06, 2009 8:28 am

The leaves are under a constant twisting force within the square holes. With leaves missing they don't fill the holes and the set screw would split the leaves apart. I think it might hold for a while but eventually the leaves would get damaged and break.

I've never done it that way, so that's just my opinion.

Tue Oct 06, 2009 8:44 am

I think in the Link pin there is an exact square they fit in, isn't there? In the Ball joint beam it's like a cross shape. The smaller ones on the outsides are alone in the cross, & the grub screw doesn't screw onto them... BUt, now that I think of it, there are 6 small ones in each stack, so, the other 4 that are in there would possibley turn & fall into the cross area where the small ones were removed from, unless you remove all 6, in that case you would have to take up the space like in the linkpin beam.

Like I said though, I've never done it, & I have only read about it. I can't find the link to the link pin beam where they removed teh leaves & showed them tacking the leave pieces back on to take up the room for the screw. I belive it was a link to someone's build on here though. Only it was an outside website, not part of the samba.

Either way, I would like to know the correct way, just in case I do end up trying it on my buggy once it's completed. Plus, it would be here to help others that are thinking of doing the same thing!

Tue Oct 06, 2009 9:32 am

"On my projects and a few buddies buggies we've reduced the torsion stacks in the front beams and seen tremendous improvements in ride quality and suspension movement."

Top or bottom tube? How many leaves from which? Large or narrow leaves?

Could you be more specific, PLEASE ! ? ! ? ! ? !

I'm narrowing in here on what, hopefully, will be the perfect solution. Shocks seem to be KYB GR2, adjusters are up in the air right now but really only change the height at which the unaltered torsion rate goes to work, stock sway bar or one size larger, no urethane, new everything and a good alignment by experts. Once I know what leaves to pull from what tubes and how many to pull, I ought to be pretty close.

Yes?

Or is there another path to the same end?

Thanks ! ! ! ! ! You guys have been wonderful !

And SHORTY . . . forget about the grub screw debate depth for now, will ya ? ! ? ! ? ! There's still more info to be gleaned on the gross anatomy of the front beam assembly. We on a narrow focus here and doing pretty good, let's not jump the rails, OK?

Tue Oct 06, 2009 10:31 am

I just looked a the leaves that are used in L/P and in B/J beams and they are different. If you only remove the two outer half width leaves in a B/J beam, the remaining leaves should pretty much hold their shape.

With a link pin suspension you need to put short sections of the removed leaves back to fill the square hole or it will eventually fail.

TC/TeamEvil wrote: Or is there another path to the same end?
In your previous thread on the same subject I posted a link to a $65 Fomula Vee anti-sway bar which will completely eliminate one stack of leaves and provide great body anti-roll.

http://www.campbellmotorsport.com/products.htm