Camber for Street and occasional Track/AutoX
 

So far I've done 2 Autocross events and 1 HPDE event in Phoenix and enjoyed it very much. The issue I have is that I am getting tire wear on the outside on all 4 tires (Michelin Super Sports) due to not enough negative camber. So I have been looking at various options to be able to adjust for more negative camber in front (and rear) for events, but then be able to fairly easily go back to a "not too aggressive" street-able camber setting (drive to and from events). I can get maybe -0.75 degrees in the front from the stock strut tower adjustment. That one is easy, but does not give me enough neg camber. I could get camber plates, but the street ride will suffer (harsh). I could get the GT3 adjustable control arms, but my wallet will suffer :eek:. For the rear, it looks like there are eccentric bolt adjustments for the control arms, but that would require a shop alignment every time...

What is my best option without spending lots of $$$? Buying a camber level alignment tool and diy? Good for the rear maybe, but can I get more neg camber in the front if I elongate the tower slots?

Edit: oh and I have stock suspension.

One of the biggest amounts of wear comes from toe settings, which you didn't mention in your post. I have the GT3 LCA and am running -2.0 camber in the front with zero toe, and in the back I am running -1.6 camber with just a touch of toe in, like 1-2mm (.08 degrees toe in per side, .16 total). With these settings my tires have been lasting a long time and getting even wear, with driving to and from the track, with a little bit of street driving in between. This is on Hankook R-S3 tires, and I don't use the car as a daily driver.

For the front, you could slot the front strut towers, or get a set of modified strut tops with relocated studs that give you more camber. You could use a 3rd party camber plate like tarret, rennline, or elephant, all of those replace the rubber mount with a monoball, and some of them will give you a little extra height in the front unfortunately. Camber plates will give you around an extra degree of negative camber in the front, so you could run something like -1.3 to -1.6 fairly easily.

I don't think you need to change the alignment between your events, with a good alignment with toe settings like I describe, I think your tire wear should be good

With a stock suspension, you simply can not get a lot of front camber
I get ~-.9 front and -1.8 rear on my stock suspension

The recommendation I have gotten from several Boxster gurus is to change to lowered springs and replace the struts with Bilstein B7's as the lowest cost with good bang for the buck

It should give me around an addition degree of camber.

You can mark the strut towers for a less aggressive front camber if you want and move them depending of your needs

My alignment with stock suspension is max camber front and rear, no toe in front and a smidge toe rear.

Also you need to think about what car class you want to run in. In our PCA rules, if you want to run in Street Stock, you can add camber plates or change the control arms, or springs, etc. Check the rules for the organisation you are running with

As a side note, MPSS is not a really good track or AX tire. Great street tire, but not track or AX.

Get a 2nd set of wheels, 17" is better and look at Bridgestone Re-71s

Lastly, it is a very slippery slope :cheers:

A cheap and simple way to get more front negative camber it to widen the slot by circa 5mm. I can get a little over -2 on the front of my car comfortably like this. I run approx -2 front and rear and use the car only on the road and there is no excessive wear. I don't feel the need for constant adjustment.

Cheapest way: change your driving style. Maybe you drive your car too hard when you turn in corners and getting out of corners. In german we have a term called "das Auto überfahren" which means you push it over the limit without need and you could be faster without doing it. I don't know to translate that into proper english.

Did you have some driving lessons with a professional instructor? I would recommend that before doing any mods to the car.

Regards, Markus

That would be cheating if you are running in a stock class

This is the best advice. Invest in really good tires and learn and practice braking and cornering technique. Once it clicks it makes a big difference.

Sounds like you could use the M030 suspension option. The added roll stiffness it provides over stock "soft" springs will mean reduced body roll, and therefore less dynamic camber change. If you care about racing class legality, M030 would likely be stock-class legal, too.

While you're at it, make sure your bump stops are like-new condition. They are not something that rarely works - they work constantly in parallel with the springs and are essential (with the stock spring configuration) to controlling suspension compression.

About the idea of changing alignment before/after each event, I remember a guy I used to autocross would change his toe at the event site, both before and after each event. He also would swapping on/off a set of racing wheels/tires, which was very common for many racing classes, but changing alignment as part of the weekend routine - not so common. This is on a front wheel drive car where front toe may be important enough to justify this, but it had the same suspension style (macpherson strut) as our Boxster's. He had a home-made trammel bar dedicated for this purpose that he'd set up laterally across the wheels, and would quickly make the adjustments on one side at a tie rod end.

Adjusting camber before and after each event, however, seems pretty crazy to me. The reason is because, adjusting camber, even a small amount, will dramatically throw off your toe setting. Toe setting will need to be very accurately adjusted after each camber adjustment. So you're basically looking at pretty much a "full alignment" there.

Wow thanks all for great advice.

Yes I went out with an instructor on my first AutoX and also on my first 3 sessions during my first PCA HPDE. Lots to learn still, but I think that I have good instincts and instructor told me I had excellent mechanics and reactions. So I was allowed to go out on the track SOLO on the 4th session. All I can say is that the 986 Boxster S surprised me on handling and grip capabilities! Exceeded my capabilities for sure! Much faster in cornering then many other cars out there.

I'm still not sure what path I want to take on the suspension, but ROW M030 sounds like a possibility. Just a little more $ than expected, especially after spending $6K this year on IMSB, new clutch, new struts, IPD plenum & TB, exhaust, racing tune, UD pulley...:eek:

Is there a market for stock suspension components?

The M030 won't help much with your camber problem. The only thing that will help is... more camber.

Your options:

1. Drill out/modify the top of the shock towers
2. Camber plates
3. Adjustable lower control arms

#1 will hurt re-sale value when the PPI turns up drilled out shock towers. I would never do this.

So, you're options are cheaper camber plates or adj LCA's. If you're going to track your car much, the LCA's are the way to go in the long run.

Hello,

can you show us pictures how the tires wear?

Regards, Markus

I've run my 2 Boxsters for circa 5 years like this with no ill effects. Whilst it's not reversible you still have the normal adjustment, you just have more! If a PPI in the U.S. marks this down for a discount then I'd hope the other cosmetic scars receive such penalties. In the grand scheme of things it's such an innocuous mod with no parts required and if you can handle a dremel and a paint brush it looks no different.

Here are some pics of the right side tires (same wear pattern on left side).

http://986forum.com/forums/uploads02...1476579393.jpg
http://986forum.com/forums/uploads02...1476579405.jpg
http://986forum.com/forums/uploads02...1476579415.jpg
http://986forum.com/forums/uploads02...1476579425.jpg
http://986forum.com/forums/uploads02...1476579434.jpg

I had the same problem before installing the adj LCA's. The outer edge would wear substantially faster than the center and inner areas. I installed the adj LCA's with -2.25 camber to get even tire wear.

Realize that this isn't a one-time fix - you'll continue to need to add more and more negative camber as you become a better and faster driver. Today, I run -3.6 negative camber in order to achieve even tire temps and tire wear.

Before LCA's:
http://i1114.photobucket.com/albums/...Misc/tire2.jpg

Today with -3.6;
http://i1114.photobucket.com/albums/...psqgnvj8k8.jpg

Another option is to replace your stock springs with lowering springs.
My understanding is that will give you around 1 deg more camber

lower the car about and inch and you'll get about 1 degree or so more camber
instead of factory strut top mount, switch to tarret monoball plates. With stock ride height, you should get about another degree of camber

As to your original question about changing camber before and after events, small camber adjustments make significant toe changes so you would need to do a full alignment each time.

Hello,

concerning to the pictures above i wouldn't say this is abnormal tyre wear for track days and racing.

If you look at the front tyre, you'll see that you've overdriven the tyre. This can't be compensated with 1 degree more negative camber.

http://986forum.com/forums/uploads02...1476579415.jpg

If you're talking about lowering and all that other stuff, please think about the consequences for the driving character of the car first. Lower, harder and more negative camber doesn't mean faster or better breaking or better stability.

Just my 2 cents

Regards, Markus

PS: This channel seems to be a good introduction for people who are interested in suspension: https://www.youtube.com/watch?v=jSFmUmVWBp0&list=PLE067A7397E1AF108

<iframe width="560" height="315" src="https://www.youtube.com/embed/jSFmUmVWBp0?list=PLE067A7397E1AF108" frameborder="0" allowfullscreen></iframe>

My dual-sport (street/track) 987 has lowering springs and GT3 arms to get -2.5F -2.0R. I run street tires and this seems to work pretty well with even tire wear, good turn-in and balance.

If I were running a softer compound tire I would want more neg. camber.

I have also hit upon very similar camber settings to Topless as ideal for my car on high performance street tires. Your results may vary - a few things to remember:

1- These are McPherson / Chapman strut cars, which by nature of the geometry, will always have about the same degree of camber gain as the amount of body roll. So, if your car rolls 3 degrees in a turn, the camber on the outside tire will roll about 3 degrees positive (don't worry about the inside - it doesn't have much load on it). So, if you have soft stock springs or a soft stock sway bar, your car will roll alot, and you may need more static negative camber to keep the outside laden tire from going positive in a hard corner, and that's what the camber setting is really all about.

2- With factory settings, these cars naturally understeer like pigs. That is intentional as it is far safer to have an understeering car than an oversteering car. So, when you start to play with camber and toe and front to rear balance, the car can become very unstable. Proceed slowly in making changes understanding what the general effects will be, and do your experimentation on a skid pad or autocross - not on a race track.

3- The primary negative effect of using a lot of negative camber is a reduction of braking capacity. Basically, the tire being tilted over while traveling in a straight line means that there is less contact patch when you brake in a straight line. This is exacerbated on the front tires by the suspension compression during braking, which causes even more negative camber than in a static condition. So, just realize that you are giving up a bit of braking capacity as you dial in more negative camber, so some compromise is in order.

Proceed carefully...