rear sway bar for swing axle

[shepherd]

I am re- building the suspension on my 62 beetle with several changes, and would like some advice.
Previous setup was, front: lowered beam, stock width, GR2 shocks, 3/4" sway bar, 175/55/15 continentals on stock rims
rear: dropped 1 outer spline, welded in blocks to act as "flop stops", KYB gas adjust, 3/4" turn six sway bar, 225/50/15 on 7.5" rims.
The car handled ok, but had a tendency to lift the inside front. There was no front suspension, as I had stock spindles and it was dropped so low. I'm just getting a new engine and trans sorted to install, so why not new wheels, tires, and go back through everything and make it better? The current suspension, still need help with the details..
Front: Narrowed 2.5" drop spindles, discs, GR2, 5" rims with 195/55/15 yokohamas. I am probably purchasing a whiteline sway bar for the front.
Rear:
Dropped 1 outer spline, notched the plates for a little more down travel, still have the droop limiters (flop stop), KYB's, and have 6" wheels with 205/60/15 yokohamas. In looking at the Turn Six sway bar, it seems to have been intended for an IRS car. I never knew that till comparing pictures, and as it came to me on a "shared" car many (more than 20) years ago I have no idea. It certainly works, but is there any possible downside to running it with the swing axle? I was going to come up with a solution that doesn't use the square cornered u-bolts to fasten the bar under the torsion housing, and maybe fasten the links to the spring plate similar to how the whiteline rear bar is. Any ideas? I would also be interested in a slightly thinner bar, my feelings were that the front was ok, but the rear could have been looser. Is there a 14-17mm bar? Can the one from a Porsche (924 I think?) be made to work?
The car is a weekend car that sees a mix of city stoplight, drags, sunday drives, and sometimes very aggressive fast twisty roads. Engine is a 2161 with 45 dells/ web 86B, trans is a 3.88RP, with super main shaft, and welded hubs. I have a mid mount and torque bar installed. I am interested in some local amateur autocross but have not inquired yet. Yes I have tried a camber compensator, and I felt the rear sway bar did more for me, as long as the suspension limiters were in. I read this
viewtopic.php?f=51&t=116069&hilit=rear+sway+bar
and several other threads, just hoping for some current opinions. Thanks in advance, SD

[buildabiggerboxer]

Hi mate, I recommend you try bigger rear torsions, 25 or 26mm SAW, you can use these with no bolt on extras whatsoever, they give an increase in oversteer, or more correctly, a reduction in under steer, exactly as fitting a rear ARB would, they also resist the jacking effect to the point of insignificance, good shocks are required to control the stiffer spring rate, remember with SA, there are some odd longitudinal radius movements on a rear ARB that don't sit well with most of the versions I've seen offered for sale, all modifications have some trade off, for that reason, 26mm is the biggest TB size I would recommend for street use, I've used 29 mm for racing, but traction can be lost on bumps and wet tarmac with these Large bars, and they can snap you into a spin very quickly with lift off over steer, so I would not use them on the street, a good driver can use up to 26 mm bars to good effect, run them with no other roll or pro roll addons and about 20' rear toe IN, Give it a try, I think you will be impressed.

[shepherd]

Thanks for the reply. I have tried larger torsion bars, but it was many years ago and maybe my driving wasn't so great back then . I think they were out of a square back, we had to run different spring plates as they were longer also. Either way, I will read up on using some stiffer bars. About the toe, you say toe "in"? I have always gotten the best handling with slight toe out, or zero, depending on what car and when..

[buildabiggerboxer]

Yes, folk here have used the T3 long torsions, with the required spring plate as you say, these are not quite "there" these days, 21 -3/4" x 26mm is the hot one,1200/1300 fitment. Toe out? Well not for high speed track use, I ran parallel just a wheek ago, IRS, and found I could not get the car back from a slide, i 180 spun, so I went back to 30' for the second race an hour later for the normal chukable trail brake technique I've grown used to. Remember, toe in shows as toe out on the reversed gauge required for setting the rear. Toe out with the big bars sounds like bad news.

[shepherd]

I have to admit, that I have very little experience setting the rear toe. I had at one point replaced the trans and spring plates, and just slid the tubes all of the way forward in the plates, and cinched it down. as expected, the rear darted all over as it hit bumps. After that I took it and had the rear set to whatever factory setting the alignment shop found which was slight toe out (as I recall). I did move the axles forward to get zero toe at one point, and it didn't seem as solidly planted so I went back to the marks the alignment shop made. Certainly the massive tires played a part, which is why I'm down to a reasonable size. Can I ask about your 20' ad 30' measurements? I'm used to setting toe in 1/16- 1/32 increments with the gauge I made.

To focus on your recommendation for the larger torsion bars, the idea is to rely on an overall stiffer rear for sway control, and not add a sway bar? If so I imagine that it's fine for smooth roads, how does it handle rougher conditions? I would worry about the rear tires skipping around, the car weighs so little. I guess that now you could say I'm running a softer torsion bar with stiff shocks, how would this compare to a stiffer torsion bar and softer shocks? Thanks again.. SD

[buildabiggerboxer]

Yes, no bars are needed, and 1/16 rear toe in will work just fine, I guess that equates to about 15' , you will find 30' is almost 1/8", quite a lot, but good for the front toe for street use, my equipment just happens to be scaled in degrees, , remember to set it AT RIDE HEIGHT,
As I mentioned earlier, all modified cars are a trade off, we have it easy on the race tracks, it's only the watch that matters, comfort, noise and vibration, or NVH as it's called these days, just don't matter, but to answer your question, it's good shocks that will make your ride acceptable on bumpy streets, I know somebody that runs 26 mm short bars in a very potent BJ car using Ohlins shocks for a quality set up that defies belief, these are at the very top of the shock range, but you don't need to go that far , although adjustable shocks will score over non adjustable because you can set the ride for comfortable touring, then crank it up for track days, I always start at the half way point on the adjusters and work from there, most times I arrive back at midway setting I started with, single point adjusters work on rebound alone and do a very good job for street cars, two way adjusters are plenty good enough even for all out racing, no need for full on 4 way for us, I consider them way way OTT for our primitive cars, not many single sweaters/drivers can get the best out of these even, it's supposed to be fun remember lol...

[shepherd]

Well, I took the chance to drive a car that is running the 26mm short torsion bars and I have to say that I was not sold on them. The car is dropped with spindles in front, and running a 3/4" front bar, no rear bar, 26mm torsion bars, GR2 all around. I felt like the rear of the car needed more weight, or to be softer. True, the rear roll was pretty much gone, the car seemed to have a bit of over steer (though I wasn't comfortable driving the car hard, as I hardly know the owner) but I felt the car skip around badly when I accelerated into a rough turn and I'm not crazy about that. So, I'm still reading and asking about a rear bar, possibly one from a 924/44 (14mm). I realize that the arc movement of the axle complicates the link between the axle and sway bar end, possibly a standard link with bushings would inhibit the suspension, so what about heim joints or small tie rod ends? I've read that some have used this bar on irs cars with success, any thoughts on suitability for a swing axle?

While I'm at it, has anyone here found a sway bar to work with a 3.5-4" narrowed beam? To fit my desired wheels, spindles, and brakes, I had to go 4" to not hit the fenders. I have a source to bend and heat treat one but it's a good chunk of change. There are a few other options on the table too, just wondering if anyone has ever done something that worked well. Thankss. SD

[buildabiggerboxer]

Whatever is causing what you mentioned is not the torsions fault, a problem at the front often appears to be at the back, all the info you need has already been covered extensively in earlier posts, but with road cars there is no datum, no one but you knows what you are trying to achieve, race cars have a datum, the watch, or lap time, but you are at odds with yourself using a narrowed beam and looking for handling, stock width is the minimum requirement, 3" wider is better. Mine is currently only 1" wider as I was too conservative building it knowing what I now know, but these things have to develop. The rule is rear AR bars are fine tuning add ons AFTER it's in the ball park, they are not requirements, and certainly not for SA.

[petew]

K, so which 25/26mm torsion bars fit my 56' oval pan?

[andy198712]

To be fair I've got the KYB GR2's and find them pretty harsh so could be that...
I want to change to konis and taller tyres (currently 195/55/15) to find that balance between handling and comfort as mentioned...