Car roaming when driving on the freeway

It sounds like your Speedster doesn't have enough caster- very typical of lowered VW front suspensions.  Caster shims are the answer-                                                   http://www.geneberg.com/cat.php?cPath=12_384_2917

Stock caster is around 2½°, which works at 60-70 mph, but really, anything over and you may find the car harder to control (something that's not a good idea when going that fast!).  For a Speedster or Coupe to handle safely at highway speeds there should be somewhere around 5° caster (all 356's were built with 5° caster from the factory).  Order 2 sets and if your car only needs 1 pair you can sell the other.

I’ll look into that.

thanks very much.
Popee

In addition to Al's caster probable suggestion, it can also be: Loose or worn steering box, pitman arm, tie rod, ball joint, wheel bearing, tires, rusted frame head .... Needs a complete inspection to locate the problem.

Steering rag-joint too ---- especially if it was replaced with dreaded poly one.

I agree with every suggestion - if the front end is set up properly, it'll track much better

... but with a front suspension already outdated when Her Doktor designed it for Der Fuhrer in the 1930s, it's not ever going to feel like anything else you're used to. The trick, if you are coming into this cold, is to gain enough experience to understand what's "normal" (for these cars) and what's not.

In the previous sentence, I put "for these cars" in parenthesis, because there's nothing normal at all in how they drive, at least not as somebody who was born and raised after 1950 would think of as "normal". Well set up, they feel like a gocart... until about 100 mph, where the pucker-factor gets pretty high. By 110, the car is skipping all over the place and feels like it might take flight.

It really might. Depending on what you consider "highway speeds", that could be getting pretty close to the gray area in suspension design.

That's why guys go on an on and on about a Mendeola/Red-9/et al front-end, why Jim Ignacio just wants to chill on CA1 up by Moonstone Beach, and why Mitch Toll waxes lyrical about learning to dance with his car.

No small amount of weirdness is just baked in the cake. You'll look for (and maybe find) ways to minimize that, but you'll never parse it all the way out. Experienced guys often forget just how weird we all really are.

Knowledge is power. Being forewarned is being forearmed.

Thanks a bunch Stan. I guess I’ll just have to dance with this little jewel. And have it checked for camber shims.

Shouldn’t be worn parts, the car only has 1200 miles on it.

@Popee

What you're seeing/feeling is called "Crest Steer" of sometimes "Bump Steer"  and it's related to the front end geometry that VW used.  Many of us have added caster shims to improve matters and they work great.

No, the steering box shouldn't be worn being this new.  The steering box could be slightly out of adjustment out of the box, and the two-step adjustment is in every VW service manual out there like Chilton's and Bentley's, but I would start with the caster shims, first.  You'll need a front end alignment after the shims are installed, so ask the tech to check for steering box play at the same time.  The way to check play is to jiggle the steering wheel back and forth when centered - There should be 1" of free play at the top of the wheel or less.  Remind him/her that this ain't no modern car with rack and pinion and he/she'll be a bit more tolerant of the results.

CIP1 and many other parts places (along with Gene Berg mentioned above) carry these shims and many of us have used them with great results.

https://www2.cip1.com/acc-c10-4190/

And I just noticed your last post - You need around 5º of CASTER not camber.  Whole different geometry going on there.

You showed a picture of a rear anti-sway bar in another thread - do you have one in the front?  Check its bushings -- and for any interference with other chassis parts.  Also check to see if you have the steering shock absorber.  Add one if it is missing or leaking. $30.

My apologies, @Popee, I was in a hurry yesterday and meant to come back and mention about checking all components and that if everything else is in good shape, it drives fine around town but still feels like it's wandering and needs constant 'over-correcting' at highway speeds, your car doesn't have enough positive caster.

Camber (whether the tire is vertical, or tipped in/out in relation to the car's front-to back centerline))  and toe-in/toe-out are easy to understand, see, and even measure, but caster is a different concept, measured by drawing a line through the ball joints (or king/link pins in an older beam) and calculating whether the car is riding and turning on the front, center or back of the tire-                                                                                                   

I believe all cars have positive front caster- my FJ Cruiser stock had close to the same caster as stock Beetles (about + 2½°), and paying attention to this detail (which consisted of outfitting the truck with aftermarket upper control arms at an extra C$800 when we did the suspension lift so caster wasn't lost- there's actually ¼-½° more now) has made the beast even at highway speeds as easy/safe to drive as when it was stock.  Other than riding ever so slightly firmer, you'd never know just by driving it that it's lifted almost 3".   Now, my son's straight front axle converted Tacoma pickup- that thing's a handful!

Lowering a VW front suspension typically reduces the caster angle, and that makes any car harder to drive and control at higher speeds.  In extreme cases a radically lowered car, when lowered just by turning the center collars in the beam, whether by cutting/welding or adjusters, can even have negative caster.  My Cal Look bug of some 40 years ago was dropped over 4" in the front by the beam only (there were no short, wider tires at the time, 135-15's were the go to front tire and offset spindles weren't a thing yet- this was the mid-late '70's) and I didn't know about caster shims.  Like your car, my bug was work to drive at highway speeds and the one time I took it up over 100 mph (I wanted to see how fast it would go) it was scary enough (a side gust pushed the car into the other lane before I could react) that I never did that again.  Shortly after I learned about caster shims and the car became much safer, with the handling being more predictable, at higher speeds.

Hope this helps.  Al

"Crest steer" is not the same as "bump steer". If one wheel is on a crest and the other in a hollow or flat, such as a crowned road, the car may pull to one side. If one wheel is on an angled piece of road and the tire isn't flat to the surface, the car may pull to the downhill side of the angled piece of roadway.

"Bump steer" is when a bump on one tire or even both alters the toe-in to pull the car one way or another, depending on whether the bump increases or decreases the steering on one wheel.

Good call on the steering stabilizer Wolfgang. I'd make sure there is a good one there.

Also, a proper 4-wheel alignment can really help the wandering along with caster shims.

My Spyder has been up to 125 mph true(GPS verified), and tracks solid at all speeds.

Also check your tire pressures. They front end has very little weight and so the pressure should also be lower. I think most run somewhere around 20-22 lbs in the front. If you've got 30+ lbs in there it'll make all the things worse.

Checked the pressure, front and rear were at 42lbs. Lowered the front to 25lbs and the rear to 32 lbs.

Going in on Wednesday for a couple of maintenance items.I’ll take pictures of the whole under carriage of the car and a video.

Thanks,

Popee

All good points, guys!  Another by-product of lowering via the beam is, as Danny mentioned, bump steer- and of course, the lower you go, the worse it gets.  At stock ride height the tie rods are close to horizontal but the more the front end is dropped the more of a V they form, and with one being shorter this is where bump steer comes from.  Not a big deal at lower speeds around town, but out on the highway can cause serious issues (and be quite disastrous)!  I have heard of people mounting the outward tie rod ends upside down (I'm guessing after some machining magic) to help level them out and minimize the problem, but offset spindles will give you the first 2½" with no need for shorter, wrongly valved shocks, no increase in bump steer and no loss of caster.  You do have to have room for them, as dropped spindles typically are ½-¾" wider.  You can make up for it by narrowing the beam the same amount, which of course means you also have to shorten the torsion leaves and drill new outer locating points, but that's no big deal...

Now ain't these cars fun?

PS- @Popee- take it for a drive, drop pressures 4-5 psi, go for another drive and then tell us what you think...

@Popee posted:

Thanks a bunch Stan. I guess I’ll just have to dance with this little jewel. And have it checked for camber shims.

I'm sure it was a typo, but to be clear, what you want are CASTER shims.

Most definitely make sure the steering box is properly adjusted and everything is tight.  Also, a number of us experienced an odd behavior where the car would track straight with the steering wheel first in one position and then in another.  The culprit there is a very slightly loose nut on the clamp holding the pitman arm on the shaft coming out of the steering box.  You can tighten it with a wrench and put all your strength into it, and still have it just loose enough to shift a tiny fraction.  That fraction translates into a surprising amount of movement in the steering wheel.  It takes a long pry bar or pipe or something to give you several to turn the nut a wee bit more to get that last bit of play out.  Took me two years (and advice from Leon Chupp) on my Speedster to figure that out.

@Popee posted:

Checked the pressure, front and rear were at 42lbs. Lowered the front to 25lbs and the rear to 32 lbs.

25 lbs in the front is still too much. 18-22lbs is plenty for the front. Rears should be about 25-28lbs. These cars are very light and those air pressure recommendations are for cars weighing considerably more.

@DannyP posted:

My Spyder has been up to 125 mph true(GPS verified), and tracks solid at all speeds.

It does.

But it's not a Speedster, which has the unfortunate side profile of a wing.

The further you drop the car, Poppy - the better it will resist this tendency (to want to take flight). We're asking you to drink from a firehose, but the sway-bar thing makes me think we need to start at the beginning and work out from there.

1. Recalibrate your expectations
2. Adjust your tire pressure to no more than 25 psi front, 32 rear. Less might be better.
3. Make sure you've got a steering damper
4. Make sure the front wheel bearings are good, packed, and properly adjusted
5. Check your ball joints, tie rod ends, and steering  arm for unusual play.
6. Grease the beam
7. Check for slop in the wheel. It will have more than you'll be used to - but the inch Gordon talked about is about the max. Look at the cage and the joint on the steering shaft - everything should be tight and good. Volumes have been written about how to adjust the steering box. Don't expect anybody but a really, really good air-cooled VW mechanic over the age of 60 to know how to do it
8. You really need to check the alignment, but be careful here. You can't just bounce over to Midas or Firestone and expect that they'll know what to do. As Lane demonstrated a couple of years ago with his Beck Supercoupe, you can't even bounce over to a race-shop and expect that they'll know what to do. You want to make sure you are toeing in, both front and back, and that you've got at least 5* of caster. The alignment really, really helps - but you aren't ready for it until you've done all the other stuff. You've got to be starting with good parts for any of it to mean anything.

NOW you're ready to talk about tires. You asked if you could run anything any wider than 185/65R15s. The answer is "probably not". What tires should you run?

Lots and lots of stuff has been written about this - but the bottom line is that nothing you do will make as much difference as nice tires... but you're not ready for nice tires until you do all 8 things on the list above.

There's a reason everybody welcomes new guys to the "madness". This is more like a cult than you knew when you bought the pretty car.

Good luck.

I’m having a great time with the car, advice, and fixing most of it myself. Drove the car at 25lbs and soooooo much better. I’m going down to 23lbs front and 30 lbs rear.

I’m a retired contractor and I’m always looking for something to do. I like staying busy with projects. So, between the house and the car, i should stay pretty busy.    

Thanks again for all the valuable information.

loving this site

Popee

@Stan Galat posted:

There's a reason everybody welcomes new guys to the "madness". This is more like a cult than you knew when you bought the pretty car.

Good luck.

Ain't it the truth!  Automotive development left these old Porsches/VW's and their technology in the dust 60 years ago.  These days we are such a small part of the automotive world- most have forgotten about us!

The cars like me…OLD. Back to a bare bones no technology car. Loving it.

Ok, 22lbs front, and 28lbs rear seams to work reallly good. 👍🏻👍🏻👍🏻

You guys are amazing.

.

Popee, Mitch here (I'm the one who likes dancing with my car).

Yes, there is a lot to check and adjust. The information above is good and honest, and frankly overwhelming if you're reading all of it for the first time. But stay calm and carry on.

The thing is, the suspension of these cars is horrendously crude by modern standards. Even with the camber and caster and toe and steering box all set up just peachy, on a rough, secondary road you're still bouncing along on something that feels like a Conestoga wagon over about 65 mph. So, like it or not, eventually you'll be dancing.

I find myself driving like I would a motorcycle — eyes glued to the road surface as much as the big picture. Where you place your wheels will strongly affect how planted or unplanted the car is. The wheels bounce a lot more on ruts and potholes than modern cars do because of the crude geometry but also because of how incredibly light the front end is.

This is why keeping front tire pressure low makes such a difference. The skinny, high aspect ratio tires originally fitted had much taller sidewalls, and the flexing of these cushioned the ride as much as the suspension did. Lower pressure reduces the 'bounce', keeping the tread on the road surface more of the time, giving you more control.

In time, your muscles and synapses learn all of this and you start to 'get it'.

Put a little fun in your life — try dancing.

.

I coulda told you 22/28 or maybe even 22/26 from the get-go..  You figured it out.

The wander: For absolute certain-sure, everything Stan said and the order he said it is correct. And here is my bet: most all of that stuff is likely just fine, except maybe the toe-in.  It's not a bad thing to check in the garage with little more than a tape measure and sharpie.  And it makes a world of difference if not right.  I think the rule around here is total toe in should be about a short 1/2 inch IIRC.  Jack the car up in front. Hold the sharpie to the center of each tread and spin the tire, marking the center of each tire tread.  Lower the car.  Back it up a lot, roll it forward a lot. measure the distance between the marks you made on the tire as close to the horizontal through the tire center as you can get it.  the front distance should be less than the back distance (toe in).  Adjust tie rods accordingly until you get it right.  Always roll it back and then roll it fwd before measuring.  Maybe you can find a good shop that can do it right with whatever fine jigs, lasers and such they have -- or maybe not.

I don't know about the fine sketch shown above, but caster is easy to see and understand if you take a look at the wheels on the chair you are most likely sitting in.  Those wheels are called casters because they both roll on the floor, and swivel about a fixed axis.  [In old VWs the king pins determined the swivel (steering) axis; later the mounting of the ball joints determined this axis.]  Where that swivel axis hits the floor/road relative to where the wheel hits the floor/road defines caster.  You want the wheel contact point behind the swivel axis intersection point, so no matter where the wheel is propelled it will always want to follow the the direction of motion.  Clearly, in  a car if the contact point of the tire is in front of the steering pivot axis that tire is going to want, with just the slightest input,  to just swivel 180 deg until it follows the motion.  On your chair that swivel is what makes it all go just right -- the chair goes pretty much exactly where you push it, as there is no steering link there to retard the swivel -- the wheels flip around to a negative caster pretty much as soon as they are pushed.  In a car where the steering gear determines the  orientation of the wheel, it will always fight any natural tendency of bad caster angle to flip the wheel around.  At speed you get wander. If the caster is negative, the whole thing is naturally stable.  If the suspension is set so you start off with  the wheel following the swivel axis, and it has no forces working to change that  (other than what you put in with the steering wheel) the car will naturally track. Further note: if you want to understand what caster can do: try pushing your car backwards any distance with nobody at the steering wheel, on level ground, and your car is going to be over to one side or the other pretty quick -- caster does that. .

You mentioned "should be good as it's new"  or some such.  Out of the box, my car had a very significant toe-OUT, and went down the highway like a drunken sailor. No body checked the toe-in at the shop, clearly.  Adjustments as described above got it all jake.

my first speedy I fixed it with a 60 lb bag of sand in the front.  yeah, yeah..I could always drill holes in it.

I think some would say 1/2" toe in is a bit much.

I came here to tell you to let some air out of the fronts, but I see you already did and it worked. Nice!

Now check the date codes on those tires. Are they older than 5 years? If so, think about getting new ones. Vredstein Sprint Classics are a good choice. Some guys like others better.

I also endorse all the below steps, and would add just one more: there's a big bolt holding your pittman arm to the bottom of the steering box. Get a wrench on it and a cheater bar, and see if you can't tighten it. If you can move it even half a flat you will feel it on the road.

Alignment specs are similar to an old Bug, but you want about a half degree negative camber instead of zero, and the afore-mentioned caster increase. Toe-in is 1/8 or 3/16".

@Stan Galat posted:

It does.

But it's not a Speedster, which has the unfortunate side profile of a wing.

The further you drop the car, Poppy - the better it will resist this tendency (to want to take flight). We're asking you to drink from a firehose, but the sway-bar thing makes me think we need to start at the beginning and work out from there.

1. Recalibrate your expectations
2. Adjust your tire pressure to no more than 25 psi front, 32 rear. Less might be better.
3. Make sure you've got a steering damper
4. Make sure the front wheel bearings are good, packed, and properly adjusted
5. Check your ball joints, tie rod ends, and steering  arm for unusual play.
6. Grease the beam
7. Check for slop in the wheel. It will have more than you'll be used to - but the inch Gordon talked about is about the max. Look at the cage and the joint on the steering shaft - everything should be tight and good. Volumes have been written about how to adjust the steering box. Don't expect anybody but a really, really good air-cooled VW mechanic over the age of 60 to know how to do it
8. You really need to check the alignment, but be careful here. You can't just bounce over to Midas or Firestone and expect that they'll know what to do. As Lane demonstrated a couple of years ago with his Beck Supercoupe, you can't even bounce over to a race-shop and expect that they'll know what to do. You want to make sure you are toeing in, both front and back, and that you've got at least 5* of caster. The alignment really, really helps - but you aren't ready for it until you've done all the other stuff. You've got to be starting with good parts for any of it to mean anything.

NOW you're ready to talk about tires. You asked if you could run anything any wider than 185/65R15s. The answer is "probably not". What tires should you run?

Lots and lots of stuff has been written about this - but the bottom line is that nothing you do will make as much difference as nice tires... but you're not ready for nice tires until you do all 8 things on the list above.

There's a reason everybody welcomes new guys to the "madness". This is more like a cult than you knew when you bought the pretty car.

Good luck.

.

If you've got a bicycle handy, you can do this little test to see and feel how caster affects steering stability.

All bikes place the axle of the front wheel forward of the axis of the steering. This 'offset' is what makes the steering want to center itself, even when you're riding hands off the handlebar.

In the garage, off the bike, you can feel the front of the bike rise a little as you turn the steering off dead center. You're actually lifting the whole front of the bike as you turn the steering. It's gravity that pulls the steering towards center. The farther forward the wheel is (off the steering axis), the higher you lift the bike as you turn.

It's easy to see how increasing rake will increase this self-centering effect and that's what you're doing when you add shims to the lower beam.

.

I recommend 1/16" to 1/8" toe-in both front AND rear. That's why I recommended a 4-wheel alignment up above. You need toe-in in the front and a tiny bit in the back as well.

And as far as caster is concerned, it's POSITIVE caster you're looking for, not negative.

Listen to Mitch "Fred Astaire" Toll, not El Frazoo about caster. Positive caster makes the car more stable. Negative=really bad, neutral=bad, a little=not enough. Stock VW is 2-3 degrees. You want 5.

And front camber: you want zero to negative 1/2 degree for most guys. I have 1.5 degrees negative, because I like it that way(and like to really rip it through the corners).

Set the rear up first: ride height gives the rear its camber(in a swing axle), then set toe-in(and thrust angle). There is no caster to set in the back.

Then, and only then, move to the front.

Set caster first, then camber, then finally toe-in.

Of course, all this alignment talk is predicated on good, tight, and well-adjusted parts throughout as Stan said.

And Stan, Spyders are airplane wing shaped too, just to a slightly lesser degree. I would also wager that the perfectly flat floorpan from the front of the car to the firewall makes them even more of a "flight risk" than a Speedster. Which is why I have a VERY slight frontward rake to mine.

And that pitman arm bolt? REALLY, REALLY tight is good, snug is not enough, it will move and cause you to lose your sanity and faith in where the car is going!

@DannyP posted:

I recommend 1/16" to 1/8" toe-in both front AND rear. That's why I recommended a 4-wheel alignment up above. You need toe-in in the front and a tiny bit in the back as well.

Danny, just to clarify on toe-in, that's 1/16" to 1/8" total, right?

@Michael Pickett posted:

Danny, just to clarify on toe-in, that's 1/16" to 1/8" total, right?

I believe that's per side - 1/8" to 1/4" total.

@Michael Pickett posted:

Danny, just to clarify on toe-in, that's 1/16" to 1/8" total, right?

Correct, Mike. Just a touch of toe-in gives me slightly quicker turn-in. Too much toe-in slightly delays turn-in, and that doesn't work for the way I like to drive.

My car has plenty of caster built-in, which means plenty of self-centering. I'm set at 1/16" total toe-in front AND rear.

I have ART(Advanced Racing Technologies) Laser toe plates, made in Staatsburg, NY not far from where I live. Very easy to use and very repeatable measurements.

https://advancedracing.com/pro...ser-toe-angle-gauge/

I have a much older version(I'm sure much cheaper too), the gauge was given to me by a close friend. I also have a set of scales(some of you have seen them) and a digital camber gauge.

I never bought the caster plates, but it isn't too hard to do. You can use floor tiles sliding on each other and a straight edge. You measure caster by using a camber gauge at 20 degrees left and right of center and comparing the readings.

I'll stand corrected on terminology, positive vs. negative.  The idea is correct. Toe in, I did not remember the total measurement, exactly.  My bad.

Most people do run 1/8" to 1/4" total toe-in, yes.