Rear Camber adjusting

IRS or Swingaxle?  Camber is a function of ride height, more so on swing than IRS.  

Rick, It's a IRS with adjustable spring plates. I'm sure the car has settled sense Greg first set the car up during the build. The rear of the car is low, but I hadn't noticed the camber change over time.

It also has the stock EMPI stocks Greg uses and an EMPI rear sway bar.

@Butcher Boy -- Welcome to the (real) madness.

If the car is really, really low, getting the camber into an acceptable range is going to be really, really hard (even with IRS).

On my IRS IM, the car came set up with 6 deg negative camber and I was getting less than 5000 mi on a set of tires. I ended up raising the back a bit and torquing on the trailing arms to get them to 4 deg negative. That's all I can get unless I get new trailing arms (which I just may do at some point).

The car cornered like it was on rails, but it ate tires at a ridiculous rate. The tire wear at 3 or 4 deg negative is bad but acceptable. Cornering is almost as fabulous, but I've got to be able to get 10,000 mi on a set of tires.

Forewarned is forearmed.

@Stan Galat posted:

@Butcher Boy -- Welcome to the (real) madness.

If the car is really, really low, getting the camber into an acceptable range is going to be really, really hard (even with IRS).

On my IRS IM, the car came set up with 6 deg negative camber and I was getting less than 5000 mi on a set of tires. I ended up raising the back a bit and torquing on the trailing arms to get them to 4 deg negative. That's all I can get unless I get new trailing arms (which I just may do at some point).

The car cornered like it was on rails, but it ate tires at a ridiculous rate. The tire wear at 3 or 4 deg negative is bad but acceptable. Cornering is almost as fabulous, but I've got to be able to get 10,000 mi on a set of tires.

Forewarned is forearmed.

Thanks Stan, Thats sound like my problem. I was shocked the rear tires were wearing so quickly. At this rate, I may need to get tires while on the road to "The Blue Smok" and back. But it handles great !!

@Butcher Boy,  like Stan has stated, the solution is in the trailing arms.

The following is from Bruce Tweddle, who pioneered the narrowed IRS arm:

The factory TA has 1.5º of negative camber built into it. By swapping them L to R, you will reduce the neg camber by 3º.

Swapping them sounds easy, but to do this you must also relocate the shock mounts and the bump stops.  You also need to drill a new hole in the spring plate to match the arms.

When I narrowed some arms years ago,  I chose to remove the camber while relocating the bearing housing inward 1 5/8".  This killed two birds with one stone.

Also from Bruce:

Loosen the bolts that attach the spring plate to the TA. Tilt the rear of the TA up for more positive camber. Down for neg.

This only gains you a little, but it might be worth it to take it to an alignment guy to see how much you gain.

@Butcher Boy posted:

Thanks Stan, Thats sound like my problem. I was shocked the rear tires were wearing so quickly. At this rate, I may need to get tires while on the road to "The Blue Smok" and back. But it handles great !!

The tires you have are NLA. Too bad you wore them out so quickly.  

@Butcher Boy posted:

Thanks Stan, Thats sound like my problem. I was shocked the rear tires were wearing so quickly. At this rate, I may need to get tires while on the road to "The Blue Smok" and back. But it handles great !!

Yeah, I was sad too.

Raising the rear end will pretty much cure the issue -- but having the car low is part of the ethos for me. You should be able to get a good alignment in the SF bay area -- you want to add as much camber as possible, then raise the back end as needed. 3 deg negative is the magic number -- tire wear gets into an acceptable range (good enough for 3 or 4 seasons), and the car still corners really, really well.

You'll want to be cornering well when you get to VA to run wit da boyz.

Personally, I would never knowingly exceed the speed limit on a public road if it was up to me -- but @DannyP and @Carlos G ain't playin' around, and what's a boy to do? I might get lost and be violated by a group of inbred banjo playing degenerates if I drop off the back, so I've got to keep up. Otherwise, I drive very conservatively (53 mph in the left lane, right turn signal on).

There's plenty of time to get it dialed in.

@LI-Rick posted:

@Butcher Boy,  like Stan has stated, the solution is in the trailing arms.

The following is from Bruce Tweddle, who pioneered the narrowed IRS arm:

The factory TA has 1.5º of negative camber built into it. By swapping them L to R, you will reduce the neg camber by 3º.

Rick -- you are a treasure. I had no idea, but this sounds like the ticket.

Guys, help me here. The various dark color highlighting makes it hard to read what you are posting.

My problem I suppose.

@Stan Galat posted:

Rick -- you are a treasure. I had no idea, but this sounds like the ticket.

I believe that @ALB is friends with Bruce Tweddle.  If we need some more technical info, he would be the guy I would reach out to.

@Panhandle Bob posted:

Guys, help me here. The various dark color highlighting makes it hard to read what you are posting.

My problem I suppose.

Nope, I had to go into the source code and remove the highlighting to read what Rick was saying.

There's a reason highlighters are yellow....

Edit: thanks for going back and fixing it @LI-Rick.

@Panhandle Bob posted:

Guys, help me here. The various dark color highlighting makes it hard to read what you are posting.

My problem I suppose.

The factory TA has 1.5º of negative camber built into it. By swapping them L to R, you will reduce the neg camber by 3º.

Loosen the bolts that attach the spring plate to the TA. Tilt the rear of the TA up for more positive camber. Down for neg.

There you go!

@LI-Rick posted:

The tires you have are NLA. Too bad you wore them out so quickly.  

yeah bummer !! I'm planning to drive the speedster back to Virginia. So I might see if I can have some new ones put on back there. I think I can make it on these if I move the rear tire to the front, add 32 pounds to make them ride more in the center. Then put the front (hardly worn tires) on the rear till they are shot. Then time for new tires on the road. I'll wait to hear from Greg if he can adjust anything. It would be a shame if you can't go cross-country without changing tires.

@LI-Rick posted:

The factory TA has 1.5º of negative camber built into it. By swapping them L to R, you will reduce the neg camber by 3º.

Loosen the bolts that attach the spring plate to the TA. Tilt the rear of the TA up for more positive camber. Down for neg.

There you go!

It looks like I have way more then !.5 of camber in this set up.

IN my search for answers I found that folks were using Porsche 944 TA's and plates. Just like Rick said, swapping the R and L and Porsche has a built-in camber adjustment. I didn't want to go thought doing the swap of arms if I don't have to. Maybe something to think about for the future like Stan says. Right now I'm trying to get the car ready for the drive.

@Butcher Boy posted:

IN my search for answers I found that folks were using Porsche 944 TA's and plates. Just like Rick said, swapping the R and L and Porsche has a built-in camber adjustment. I didn't want to go thought doing the swap of arms if I don't have to. Maybe something to think about for the future like Stan says. Right now I'm trying to get the car ready for the drive.

I believe the 944 arms that have the built in adjusters are the aluminum arms.  I'm not sure, but I think they increase the track.  A guy recently installed these over on the samba, and it turned into a sh*t show.

@Butcher Boy posted:

It looks like I have way more then !.5 of camber in this set up.

That camber is what is built into the arm, NOT what you get for final camber.  That camber was configured for a stock ride height beetle.  Your car is much lower, therefore a lot more negative camber.  Throw an angle finder on your wheel and you will get a rough idea what you currently have for camber.

@Stan Galat posted:

Yeah, I was sad too.

Raising the rear end will pretty much cure the issue -- but having the car low is part of the ethos for me. You should be able to get a good alignment in the SF bay area -- you want to add as much camber as possible, then raise the back end as needed. 3 deg negative is the magic number -- tire wear gets into an acceptable range (good enough for 3 or 4 seasons), and the car still corners really, really well.

You'll want to be cornering well when you get to VA to run wit da boyz.

Personally, I would never knowingly exceed the speed limit on a public road if it was up to me -- but @DannyP and @Carlos G ain't playin' around, and what's a boy to do? I might get lost and be violated by a group of inbred banjo playing degenerates if I drop off the back, so I've got to keep up. Otherwise, I drive very conservatively (53 mph in the left lane, right turn signal on).

There's plenty of time to get it dialed in.

I hear you Stan, I've been known to venture into the "oh crap" zone a few times in my cars. Off-roading and a few driving schools have taught me control and balance. Age has taught me survival. I'm going to try to keep up .......... If I don't, I will see you back at the hotel with a cold one, waiting to hear the stories. Just remember, I need to be able to drive myself back home to Kalifornia. Parking it in a Virginia Oak is not on my list and I'm sure for no one else. Nor is flying home without the car. I plan to have a good time on a road trip adventure in a plastic crown car. Meet you folks will be icing on the cake.

@LI-Rick posted:

That camber is what is built into the arm, NOT what you get for final camber.  That camber was configured for a stock ride height beetle.  Your car is much lower, therefore a lot more negative camber.  Throw an angle finder on your wheel and you will get a rough idea what you currently have for camber.

Thanks Rick, Good idea !! I will head to Harbor Fright tomorrow and see if they have one. If not I know where to barrow one.

I've been running 3 to 3.5 degrees negative camber(per side) for YEARS on my Spyder. I get decent tire wear.

You need negative camber both front and rear for good handling, especially swing axle cars. IRS needs some negative camber, but not as much as swing.

I'm going to suggest you've got way too much toe-in in the rear. Probably on the order of 3/8" to 1/2". Which will ruin tires in very short order.

I'd take it to an alignment shop that knows Beetles. Don't use factory specs.

1/16" total toe-in both front and rear.

1 to 1.5 degrees negative camber in the front. 3-5 degrees positive caster.

In the back, about 1 to 2 degrees negative camber for IRS, 3 or a little more for swing axle.

You may very well have too much negative camber after reading the last couple posts. Sorry if I misled you, Dave.

@DannyP posted:

I've been running 3 to 3.5 degrees negative camber(per side) for YEARS on my Spyder. I get decent tire wear.

You need negative camber both front and rear for good handling, especially swing axle cars. IRS needs some negative camber, but not as much as swing.

I'm going to suggest you've got way too much toe-in in the rear. Probably on the order of 3/8" to 1/2". Which will ruin tires in very short order.

I'd take it to an alignment shop that knows Beetles. Don't use factory specs.

1/16" total toe-in both front and rear.

1 to 1.5 degrees negative camber in the front. 3-5 degrees positive caster.

In the back, about 1 to 2 degrees negative camber for IRS, 3 or a little more for swing axle.

Thanks for the set-up Danny. I have a VW performance shop a few miles from me. I can't remember if they have an alignment rack, but I will call them and see if they can check it out. They worked on my Granddaughter VW Euro-Van when she owned it.

@Butcher Boy posted:

Thanks Rick, Good idea !! I will head to Harbor Fright tomorrow and see if they have one. If not I know where to barrow one.

Harbor Freight has them.  $5.

I bought one of these:

https://www.lowes.com/pd/Klein...wcB&gclsrc=aw.ds

Digital and reads down to 1/10 degree.

We use them in FV. Set it on one axle tube and zero. Move to the other side and it reads total rear camber. Pretty handy.

After wading through this thread, I agree with Danny.  Rear IRS VWs (NOT swing arm) don't change camber much, if any, going straight up and down.  That's what makes them better.  Swing arm changes camber a lot up and down, IRS does not.   Whatever adjustment is available is done at the hub unless you spring for custom diagonal arms.  

Most toe and camber issues can be fixed by adjusting the hub on the spring plates.  In my experience, the hub flanges are not flat or parallel, they are trapezoidal and affect toe and camber by moving the hub around versus the spring plates (Up/Down - Fore/Aft).  Some that are really out can be saved by inserting steel wedges between the hub and spring plate (this is very rare because VW mechanics usually just replaced the diagonal arm).  

A competent early VW shop should be able to sort this out IF they have an alignment deck and a good tech.  IIRC, the last time I had my alignment done (1969 Beetle IRS or any 924 Porsche suspension), by a guy who knew aircooled VW suspensions, he made up special caster shims for the front to get me to 6º caster AND had to insert a minor wedge on the driver's side rear to get the rear to spec.

From the Bentley Manual:

"If the total toe angle exceeds 15´ and the camber exceeds -2º, loosen the diagonal arm/spring plate mounting bolts and shift the arm's position to obtain the largest possible positive camber.

Recheck the toe angle and, if necessary, adjust it by moving the diagonal arm foreward or rearward in the slotted spring plate holes.  if the camber varies by more than 45´, the torsion bars must also be adjusted.  

The relationship between all preceeding adjustments is very important.  Often you may establish the correct setting for one, only to find that it has upset another."

Rear IRS Torsion bar adjustment for ride height:

https://www.speedsterowners.co...rear-ride-height--vw

You'd be surprised, Gordon. As you dump an IRS car, the camber increases -- not the extent of a swing axle car, but it definitely does increase.  A well designed suspension always increases camber as it moves through the range of travel (why control arms are unequal length, etc.) and a dumped car is just picking a ride height about half-way through the OE VW travel. IRS is worlds better than a swing axle in this regard (sensible camber increase), but guys with really low IRS cars (like _*ahem* "some people") deal with a lot of negative camber.

As I said (and as Danny agreed) 3 deg is the magic number. 1.5 deg with IRS would be great on the highway, but you'll never get it without either riding high (like a scary F150 monster truck) or getting new trailing arms.

You can get 3 deg by adjusting to full positive camber (in the mounts and on the eccentrics, if your car is so equipped) and the ride height up until you're at 3 deg negative. Tire wear is good enough to go coast to coast a couple of times, and cornering will be fantastic.

I’m with Stan. Gordon has obviously never dropped an IRS car really low.

Gordon, I have never seen nor heard of putting a wedge between the spring plate and trailing arm mount in 30 plus years of playing with VW’s.  Could you please point me to some place where this is shown?

Intrigued by this thread as it’s a description of Bridget’s problem with potential solutions I had not heard of. Thanks!

Thanks guys! My 75 year old eyes aren't what they used to be and I truly want to be able to read what you post.

https://apps.apple.com/us/app/...ng-tool/id1439825258

@LI-Rick posted:

That camber is what is built into the arm, NOT what you get for final camber.  That camber was configured for a stock ride height beetle.  Your car is much lower, therefore a lot more negative camber.  Throw an angle finder on your wheel and you will get a rough idea what you currently have for camber.

Got home from work and picked up a protractor from HF. Looks like I have 3` of negative camber as the car sits. I'm hoping my call to Greg tomorrow will help me get this thing adjusted where the tires will have some life. I hope raising the car a bit will help also. Thanks to all you guys for your comments and suggestions. I'll let you know what I find out and how things got fixed.

Excessive toe out can cause rapid tire wear also.  You really need to get the car on an alignment machine, operated by a competent technician.

@Butcher Boy posted:

Looks like I have 3` of negative camber as the car sits.

That's actually great.

You shouldn't be experiencing the tire wear you're seeing from 3 deg neg. I'm not sure how far I trust the $5 harbor freight angle finder, but it's not -6 deg anyhow.

@DannyP and @LI-Rick are spot on. I'd bet it's toe. You need to get it on an alignment rack.

Yeah. Mine's about 6 on the passenger side. Three, I'd like.

@Stan Galat posted:

That's actually great.

You shouldn't be experiencing the tire wear you're seeing from 3 deg neg. I'm not sure how far I trust the $5 harbor freight angle finder, but it's not -6 deg anyhow.

@DannyP and @LI-Rick are spot on. I'd bet it's toe. You need to get it on an alignment rack.

Stan, it was a quick check to give Greg some info when I call him. I hope the info I get from Greg about how he set it up, will give me a better idea. I know he only built a few Subaru speedsters. He build a personal speedster and mine that was the last Subaru powered build. I don't know if he had the right alignment figured out for the added rear weight. I believe the car has settled a bit from when I picked it up. But,I will find someone here to align it or drive it down to Greg for the fix. I have a few shows to attend coming up, but I think there is time to get it right before September.

Hi All, talked to Greg at VMC this morning about my tire wearing and the camber being off. He said it sounds like there might have been a shift in the 3 bolts that attach to the trailing arms. This could cause the camber and the toe to be off. He said he could fix it and we will schedule the fix at the end of July. He said the fix would be to align the car then drill a 4th hole through the spring plate and lock it down with a 4th bolt that is not slotted. I will also go with Koni shocks and add a mid trans mount while its down there. So that's it for now ............ Again thank you guys for the advice and support.

The Gene Berg mid mount is really nice!  

http://www.geneberg.com/produc...amp;products_id=1064

@LI-Rick posted:

The Gene Berg mid mount is really nice!  

http://www.geneberg.com/produc...amp;products_id=1064

Thanks LI-Rick, I'll check it out

I agree.  I installed a Berg GB 643 Mid-mount 6 or 7 years ago at the same time I installed my EMPI C12-6518-11 truss bar that I got from CIP1.  Both well made, reasonably easy installation (complete instructions are included) and helped to stiffen things up back there, although as Stan mentioned, they transmit a bit more noise into the cockpit.