a4944

I was considering camber plates to adjust camber at the track but backed off when I found out that it would also change the toe. Are there other benefits to camber plates for a DE car besides easier adjustability? Do they help maintain camber in turns? I don't mind spending the money on them if there is noticable benefit. I need to get the shocks revavled anyway.

Thanks,
Mark

A930Rocket

Why would they change toe? And if does, can't you just make the alignment adjustment to your specs?

Probably a little more adjustment is available from them in addition to ease of adjustability.

They also help with removing the play at the top of the strut. Giving a little more precise handling and feedback.

Just my .02

DAR951

Changes in camber cause changes in toe regardless of how they are made (camber plate or essentric bolts).

In addition to ease of adjustability (and if you are changing often between street and track settings that counts for a lot) they increase the range of adjustment considerably, adding perhaps an additional 1-2 degrees of negative camber over the bolts alone.

As for maintaining camber in turns, plates are slightly less compliant than the stock strut bearings, so in a very small way they may hold camber settings better than stock, but not so that you could tell much, if any difference in handling due to that factor alone.

RedlineMan

Hey Mark;

Camber does indeed change toe. Look at the geometry of a front end. The tie rod end mount arm is ABOVE the ball joint, and places the rod end a ways in front of it as well. Because the pivot (ball joint) is BELOW the rod end, as the top of the strut is moved inward, the tie rod arm will try to move inward as well... except it can't because it is stopped by the tie rods and steering rack. This causes the sturts to rotate outward on both sides as the top of the strut comes in, INCREASING toe-out.

Now, if you set your car just right, and have an idea of what camber you want at the track, you can hit a good toe value for both your street and track settings.

This is of course a bit of a compromise situation. Toe changes are not too drastic as long as your camber change is not either. A change of 1 degree will not ruin your toe settings, but you sort of have to START with proper toe and a decent amount of negative camber to get track camber and reasonable toe. Make sense? I know... tricky!

OK, if you start with 0 camber and 1/16th toe in (the stock front setting IIRC), and seek to go to -3 camber, I think you will be toed out too far. If you start with -1.8 and 1/16th toe in, and go to -3, you may be in an acceptable toe out range. See? You'll have to play with it to know where you need to start.

You do not really want toe out unless your car is "spherical bearing-ed" and pretty much track only. You don't want more than 1/16th toe out in ANY event!

Clear as mud, eh?

Oh... and you won't notice any difference in how the car feels with camber plates alone.

Jim @ EuroWerks

It will definitely help with the range of camber adjustment especially if either the strut or frame is tweaked. Not the best situation or the best fix. But it would help someone get by with other benefits as well. Like ease of adjustment at the track. If you are planning to get serious about the track stuff, the next thing will be the camber gauge and stringing the car for toe adjustments at the track. then, keep alot of records including humidity and temp. ofcourse a pyrometer as well! Jump in, here we go!

A930Rocket

You're right. I left out all my other suspension changes when I said that.

DAR951

You should note, however, that the RATE of toe change as camber is changed is dependent on caster angle.

So unless you have identical caster settings, a one degree change in camber will result in a different toe change for you than it will for someone else...

BTW, setting toe angles is one of the easier alignment chores, requiring only a set of toe plates and a couple of tape measures... the cheapest of the alignment tools. So there's no real excuse for not resetting it properly each time you make a change to your camber angle. Also, excessive toe is probably the single factor most responsible for early and unnecessary tire wear... so get it right.

a4944

Thanks all. I'll keep it as is for now since I'm running street tires. I have 1.5 neg camber all around and 0 toe in the front. I just got back from VIR full course. I put in a 30mm torsion bar in the back and 350 lb springs in the front during the off season. I was pleased with the setup, seemed to work pretty well. I have yellow internal adjustables Konis set to full stiff. It still had more body roll than expected (I also have M030 sway bars). It felt OK in the car but there was a photographer and the pictures showed more roll than I expected. I'm not too worried since it felt OK.

The steering felt skittish at high speeds (~145 down back straight). It was not as stable as I would like but manageable. I rebuilt the ball joints before the event (the races were bad) and replaced the tie rod ends. I'm thinking the tires may be out of balance (I think some weights fell off in back) or it's from the 0 toe setting. Any educated guesses on this? Should I expect this with 0 toe in front? I have an Audi A4 and the steering is much more precise than the Porsche. I realize the Porsche is 18 years old, just curious if that is to be expected or if I should be hunting down a potential problem.

Thanks,
Mark

DAR951

"Skittish" is pretty subjective... a track setup with high camber angles will often feel "darty" but at 1.5 degrees negative that's probably not your issue. A place to start that is realatively easy is the toe angle - try a touch "out" instead of zero (1/16 or 1/32nd). This will tend to pre-load the steering joints and may help a little with straight-line as well as turn-in.

Also check your four wheel alignment (Shop with the good Hunter equipment, or string the car yourself) and make sure everything is pointed the right way relative to everything else. Once you establish this baseline, front end changes are easier to understand. Also note that rear toe adjustment requires a special Porsche tool (special socket for the essentric).

Good luck.

A pretty good basic reference for understanding race alignment can be found at the Longacre web site in their "Tech" Pages. http://www.longacreracing.com/articl...at.asp?CATID=2

Jack667

Just to clarify - in PCA club racing, in the stock classses, camber plates are allowed if the are pinned. For a car with solid bushings, stiff springs, shock tower brace, etc - would pinned camber plates provide any benefit over the stock bushings? I understood that there was a benefit, in that they helped to stiffen the car...

RedlineMan

Jack -

They of course DO make a difference, but if everything else is rubber you won't notice. If you did mods in the reverse and did platers LAST, you probably would tend to notice them. They are a 10/10ths mod in my estimation. You will get "far more" out of solid control arm bushings.

Mark -

-1.5 is indeed not very much camber. I would tend to think you were reacting to the 0 toe. I would still recommend AGAINST going to toe-out. Some suggest the rubber bushings will deflect and increase this toe out to unacceptably high levels in braking zones. this is a therory, but it does seem to have some merit.

My 84 has all the OE rubber bushings with the exception of camber plates. It is set at -2.5, max caster, and 1/16th toe out. I do not notice any agregious activity from the toe settings, but the car does require vigilance at all times. It is worse on the street where the surface can be crowned, rutted, or potholed. Definitely has a mind of its own if you are not paying attention! On the track it is excellent.

Your Audi, being a "more modern" car, likely has FAR MORE caster than the 944. Early 44's can't get much caster at all. The later 44's can get about 3.1-3.3 even caster, which is fairly decent. Some modern cars are set at 6-7-8 degrees stock!

Oh... and you are not so stiff as to eliminate body roll. If you saw pictures of before and after your spring change you would see a dramatic difference, trust me! You won't have to change side mirrors as often now either!!

For reference: 500F/450R