Camber Settings for Track

[1MOREMOD]

Originally Posted by Datka

As far as I understand slight bit of toe out in front helps turn in on the track, not understeer.

Toe out would make the csr more darty and less stable at speed but turn in would improve.

[lutfy]

Originally Posted by intercool

So I recently purchased an E92 with Camber plates from a fellow forum member. He has camber plates on it with H&R lowering springs and HD Bilstiens. He sets the camber at -2.2 for track and then back to stock afterwards as it is a daily driver.

I talked with one of my mechanic friends and he said that just adjusting the camber isn't a good idea because it affects toe and will mess the bushings.

My question, if I change the camber for the track, do I need to do an alignment before and after events? If I bypass alignment, will it cause issues?

I tried this hybrid setting. Get on an alignment rack and get as much toe in (factory spec) with -1.8 camber (for street). Then start dialing in more camber until you get to the high end of toe out (factory spec). Camber was in line of -2.3 and -2.4 for me. I marked the plates. I was seeing more tire wear with this and decided to stick with 0 toe and -2.4 static camber and been a happy tropper since.

Nothing to do with the bushings what so ever. Just three bolts on top of the plates.

Lutfy

[bigjae1976]

Originally Posted by 1MOREMOD

Toe out would make the csr more darty and less stable at speed but turn in would improve.

I sometimes run a little tiny bit of toe out on my E46 to help with turn in. Totally unnecessary on the E9X.

[Pistonheed]

Originally Posted by bigjae1976

I sometimes run a little tiny bit of toe out on my E46 to help with turn in. Totally unnecessary on the E9X.

Can you explain why you think it's totally unnecessary on the E9X? I ran toe out on my M3 CSL and the initial turn in was brilliant. I am now moving to the E9x platform and keen to replicate that initial turn in feeling.

[dogbone]

Originally Posted by intercool

So I recently purchased an E92 with Camber plates from a fellow forum member. He has camber plates on it with H&R lowering springs and HD Bilstiens. He sets the camber at -2.2 for track and then back to stock afterwards as it is a daily driver.

I talked with one of my mechanic friends and he said that just adjusting the camber isn't a good idea because it affects toe and will mess the bushings.

My question, if I change the camber for the track, do I need to do an alignment before and after events? If I bypass alignment, will it cause issues?

Currently, my E90 M3 is a dedicated, gutted/caged track car with over 100 tracks days on it. But for 3 years, it did dual duty street/track, so I changed camber all the time between track and street. (I have an active build thread over in the Track section of the forum. We talk about all kinds of stuff like this on that thread. I encourage you to check it out: http://www.m3post.com/forums/showthread.php?t=1158445 )

After 6 years of running this car on track, here are my conclusions regarding camber:

-In my opinion, when considering an E9x M3 and tire wear, -2.2º camber is not enough for track use: The tires on the E9x M3 platform benefit from as much camber as you can give them in the front. With running minimal camber in the front (like -2.2º), the car tends to lean over the outside edge of tires and simply destroys the front tire edges very quickly. When I moved to Hankook TD's, which are considered a soft racing tire, I was still running low camber settings. The edges of a 265/35/18 TD would be almost fully destroyed in just two sessions. The rest of the tire looked brand new, but the outside edges were just decimated. I decided to experiment by slamming my camber plates inward to maximum just to see what would happen. The tire edges faired MUCH MUCH better. I could get much more life from tires. And the car drove great. The edges are still the first thing to go, but it takes much longer for them to cord than with less camber. My advice is to have the car aligned with max camber for track use, and then just move to minimum camber for street use. For me, on Vorshlag camber plates and a car that's lower than stock on JRZ, max is around -4º. Your tire edges will thank you. And the car really does feel fine. I have no problem with braking. Turn in feels great. And my tires last a hell of a lot longer than with less camber.

I want to reiterate that my settings aren't a crappy compromise. I didn't increase camber to save tires and then lose performance and just live with it. The car is very fast on track with the settings I use. (This car, with these settings, has won several time attack events and is usually one of the quicker cars out there.) And now that the car never sees the street, and I could use whatever settings I want, I still use the same max camber settings,

-Regarding the potential side effect of toe change when you change camber----I wondered about this so I did a bit of homework. I went to an alignment shop that had a laser rack. I had them do the full alignment based around maximum camber--as far as the plates could shove inward. The camber was around -4º. Once the alignment was done, I asked him to change the camber to it's most minimum setting possible so we could see toe change---basically just pulling the top of the damper as far outward as possible. So, he did that. The minimum camber was around -2.2º. The toe change was VERY minimal. It changed 0.02". So, all the worry of the toe settings changing between street and track is completely overblown. I'm quite sure that very few drivers could detect that toe change. So again, I say get your car aligned with the maximum camber allowed by your camber plates. This will ensure that you're in great shape on track. And then just pull the dampers all the way out to minimum camber for street and the car will drive TOTALLY fine on the street. I did exactly that for several years.

-Regarding bushings----I changed camber settings easily more than 100 times (basically changing before and after each event over the course of 70-80 events), along with driving the car quite hard. I never had any bushing problems.

-OEM Rear camber settings are fine on track. Factory is around -2.2º. I still run that and my rear tire wear is perfect---even on soft racing tires, the wear is even across the tire. No need for super high camber in the back.

-To change camber to max (inward), both front wheels need to be in the air. I couldn't push the damper inward if either front wheel was on the ground. I wanted to change camber at the track so I could save my street tires the stress of driving to and from the track on max camber. This required me bringing two floor jacks. hehe yeah, it's a commitment.

-A fatter tire resists edge wear better than a narrow tire. When you put a fat tire up front, and then use a lot of camber to get that outside edge up, you get longer life from that fat tire because the car can't roll over it as easily. A skinny tire just gets destroyed underneath an E9x M3. When using harder rubber compounds, this tendency is hidden to some extent because the tire compound lasts longer. But when running softer race tire, it becomes apparent after just one session. Of course, max tire width up front is affected by the suspension on the car. I don't know what's possible with Bilsteins.

-If tire life is important to you on track then run a square tire setup and Rotate Rotate Rotate all around the car. Running staggered can be nice, but it limits your ability to rotate. Rotating tires is a bit of a pain, but sharing the stress by rotating makes them last quite a bit longer. With the softer tires that I run now, I never go more than 2 sessions without rotating. With a harder rubber compound, I know people will run a whole day with the tires in the same position. I would still recommend rotating once in a day if possible. I know it's not fun.

So, to recap: get an alignment with max camber. Change back to minimum camber for street driving to save the inner edges of your street tires. Have fun!----except when rotating tires.

[bigjae1976]

Originally Posted by Pistonheed

Can you explain why you think it's totally unnecessary on the E9X? I ran toe out on my M3 CSL and the initial turn in was brilliant. I am now moving to the E9x platform and keen to replicate that initial turn in feeling.

The E9X doesn't have the understeer issues the E46 has. The E46 has a ton a camber change that you need to deal with.

I sometimes run a little less camber with a little bit of toe out to help with turn in.

The E90 has less dynamic camber change and can easily throttle steer through corners. That makes toe out unnecessary and reduces tire wear.

[135]

Originally Posted by dogbone

Currently, my E90 M3 is a dedicated, gutted/caged track car with over 100 tracks days on it.
http://www.m3post.com/forums/showthread.php?t=1158445

After 6 years of running this car on track, here are my conclusions regarding camber:

-In my opinion, when considering an E9x M3 and tire wear, -2.2 camber is not enough for track use: The tires on the E9x M3 platform benefit from as much camber as you can give them in the front. With running minimal camber in the front (like -2.2), the car tends to lean over the outside edge of tires and simply destroys the front tire edges very quickly. When I moved to Hankook TD's, which are considered a soft racing tire, I was still running low camber settings. The edges of a 265/35/18 TD would be almost fully destroyed in just two sessions. The rest of the tire looked brand new, but the outside edges were just decimated. I decided to experiment by slamming my camber plates inward to maximum just to see what would happen. The tire edges faired MUCH MUCH better. I could get much more life from tires. And the car drove great. The edges are still the first thing to go, but it takes much longer for them to cord than with less camber. My advice is to have the car aligned with max camber for track use, and then just move to minimum camber for street use. For me, on Vorshlag camber plates and a car that's lower than stock on JRZ, max is around -4. Your tire edges will thank you. And the car really does feel fine. I have no problem with braking. Turn in feels great. And my tires last a hell of a lot longer than with less camber.

-So again, I say get your car aligned with the maximum camber allowed by your camber plates. This will ensure that you're in great shape on track.

So, to recap: get an alignment with max camber.

You mention that the aim should be to dial-in as much camber as possible at the front to avoid destroying the outside tyres' edge.
But, even when you have -4° camber, while the outside edge wear, and thus tyre life, and driveability is much improved, the outside edges are still the first to go.

So, how much camber (obviously more than -4°) do you think would be ideal, i.e. to get even inside-edge-to-almost-outside-edge wear?

Do you use a pyrometer to measure temps across the tyre? If so, what does it tell you for -4° camber?

[135]

Originally Posted by 135

You mention that the aim should be to dial-in as much camber as possible at the front to avoid destroying the outside tyres' edge.
But, even when you have -4 camber, while the outside edge wear, and thus tyre life, and driveability is much improved, the outside edges are still the first to go.

So, how much camber (obviously more than -4) do you think would be ideal, i.e. to get even inside-edge-to-almost-outside-edge wear?

Do you use a pyrometer to measure temps across the tyre? If so, what does it tell you for -4 camber?

Bump for dogbone

I'd also be interested to know what your front and rear undamped natural ride frequencies are on your M3 with 600/900 spring rates.

[Pistonheed]

Originally Posted by bigjae1976

The E9X doesn't have the understeer issues the E46 has. The E46 has a ton a camber change that you need to deal with.

I sometimes run a little less camber with a little bit of toe out to help with turn in.

The E90 has less dynamic camber change and can easily throttle steer through corners. That makes toe out unnecessary and reduces tire wear.

So, do you think the E92 has a better chassis than the E46?

My friend preferred my E46 to his E92 for feel and front end. He didn't like the way the 92 rolls in the corner so he spent all winter taking ~150kgs out of it and welding in a cage. Suffice to say it turns in better now and rolls less but unfortunately we won't be able to do another back to back test.

[dogbone]

Originally Posted by 135

You mention that the aim should be to dial-in as much camber as possible at the front to avoid destroying the outside tyres' edge.
But, even when you have -4° camber, while the outside edge wear, and thus tyre life, and driveability is much improved, the outside edges are still the first to go.

So, how much camber (obviously more than -4°) do you think would be ideal, i.e. to get even inside-edge-to-almost-outside-edge wear?

Do you use a pyrometer to measure temps across the tyre? If so, what does it tell you for -4° camber?

I think you will find very few people who have ever achieved much more than -4º of camber on this platform. (Sometimes mine is measured at -4.1º depending on the machine/day/magical camber fairies floating around the car.). What I mean is that I doubt hardly anyone with an E9x M3 has tried -5º or -6º. The reason is because there are logistical hardware limits on the currently available parts that prevent going further.

The camber plates that are available for purchase have limits on how far you can push them inwards. I have had Ground Control (both street and race plates) and Vorshlag. I like the Vorshlags the best and they are in the car right now. For me to get to -4º, the Vorshlags are at their limit. This limit puts the JRZ damper-top around 1mm from the inside edge of the strut hole. So, even if the Vorshlag could push in further, there is the strut hole getting in the way. So to achieve significantly more camber than -4º would require a custom camber plate of some sort, plus you'd have to grind the inner portion of the strut hole so you could push the damper further inward. I have not looked into the viability of either of these things.

Also, one needs to consider the driving characteristic of the car with super extreme amounts of camber. Worrying about wearing a tire evenly is generally a legitimate concern, but if the tire is cambered inwards so severely, you could be limiting your braking power due to reducing the contact patch while the car is going straight. To be honest -4º looks pretty aggressive in the camber department already. The wheel has a very noticeable angle to it. It does not take any kind of expert to see how much the wheel is leaning inwards.

Here's the bottom line for me after several years of messing around with this: With max camber on the Vorshlag plates, and running a square setup with the fattest tires I can fit, I can keep tires alive long enough to the point that they're very much worn down and they're not very grippy anymore. A Hankook TD Soft 295/30/18 can be driven hard and rotated for 20+ heat cycles. At the point that I cord them, they are not driving anything like a new TD. At that point, I am satisfied that I've gotten my money's worth.

To add a bit more background to the story: My friend has an M3 that is very similar to my setup. For quite some time, he had been running maximum camber like me. And his tire wear was similar to mine---it was acceptable. However, he had done a number of changes to the car, including springs rates and ride height, messing with aero, etc, and he wasn't happy with how the car was driving. So, he decided to get a high end alignment from a very respected shop. They recommended against running so much camber. (I never did hear why.) So, after talking to him about what he wanted from the car in terms of drive characteristic, they did their alignment. The alignment reduced front camber to -3.2º. He brought new tires to the track. The edges of the front tires were severely worn before the end of that first day. He decided to go back to max camber and he slowed the edge wear back to, what he considered, a more acceptable rate.

To be honest, I have not measured tire temps in a long time. It's not hard to guess that the outside is seeing higher temps given the wear.

And regarding your question about ride frequencies, I have never done any analysis like that. Years ago, JRZ made the initial recommendation for spring rates. Over time, I experimented with a few spring setups to see what they felt like. But I've never dealt with a shop that calculated ride frequencies as far as I know. Are you knowledgeable in this area? Can you describe how one measures this?

[bigjae1976]

Originally Posted by Pistonheed

So, do you think the E92 has a better chassis than the E46?

My friend preferred my E46 to his E92 for feel and front end. He didn't like the way the 92 rolls in the corner so he spent all winter taking ~150kgs out of it and welding in a cage. Suffice to say it turns in better now and rolls less but unfortunately we won't be able to do another back to back test.

The E9X is a significantly better chassis and suspension design but the steering tends to be too light. The E46 does have a more precise feel to it.

In terms of performance, the E9X M3 is as fast as a well modded E46 with bolt ons. The only e46s that stand a chance have aero and all of the bolt ons.

Funny story and I would not suggest this mod but my E90 M3 is perfect ever since the p/s fluid foamed up. The rack groaned a little so I flushed the fluid. My partially damaged p/s system is perfectly weighted. I love it.

[135]

Originally Posted by dogbone

I think you will find very few people who have ever achieved much more than -4º of camber on this platform. (Sometimes mine is measured at -4.1º depending on the machine/day/magical camber fairies floating around the car.). What I mean is that I doubt hardly anyone with an E9x M3 has tried -5º or -6º. The reason is because there are logistical hardware limits on the currently available parts that prevent going further.

The camber plates that are available for purchase have limits on how far you can push them inwards. I have had Ground Control (both street and race plates) and Vorshlag. I like the Vorshlags the best and they are in the car right now. For me to get to -4º, the Vorshlags are at their limit. This limit puts the JRZ damper-top around 1mm from the inside edge of the strut hole. So, even if the Vorshlag could push in further, there is the strut hole getting in the way. So to achieve significantly more camber than -4º would require a custom camber plate of some sort, plus you'd have to grind the inner portion of the strut hole so you could push the damper further inward. I have not looked into the viability of either of these things.

Also, one needs to consider the driving characteristic of the car with super extreme amounts of camber. Worrying about wearing a tire evenly is generally a legitimate concern, but if the tire is cambered inwards so severely, you could be limiting your braking power due to reducing the contact patch while the car is going straight. To be honest -4º looks pretty aggressive in the camber department already. The wheel has a very noticeable angle to it. It does not take any kind of expert to see how much the wheel is leaning inwards.

Here's the bottom line for me after several years of messing around with this: With max camber on the Vorshlag plates, and running a square setup with the fattest tires I can fit, I can keep tires alive long enough to the point that they're very much worn down and they're not very grippy anymore. A Hankook TD Soft 295/30/18 can be driven hard and rotated for 20+ heat cycles. At the point that I cord them, they are not driving anything like a new TD. At that point, I am satisfied that I've gotten my money's worth.

To add a bit more background to the story: My friend has an M3 that is very similar to my setup. For quite some time, he had been running maximum camber like me. And his tire wear was similar to mine---it was acceptable. However, he had done a number of changes to the car, including springs rates and ride height, messing with aero, etc, and he wasn't happy with how the car was driving. So, he decided to get a high end alignment from a very respected shop. They recommended against running so much camber. (I never did hear why.) So, after talking to him about what he wanted from the car in terms of drive characteristic, they did their alignment. The alignment reduced front camber to -3.2º. He brought new tires to the track. The edges of the front tires were severely worn before the end of that first day. He decided to go back to max camber and he slowed the edge wear back to, what he considered, a more acceptable rate.

To be honest, I have not measured tire temps in a long time. It's not hard to guess that the outside is seeing higher temps given the wear.

And regarding your question about ride frequencies, I have never done any analysis like that. Years ago, JRZ made the initial recommendation for spring rates. Over time, I experimented with a few spring setups to see what they felt like. But I've never dealt with a shop that calculated ride frequencies as far as I know. Are you knowledgeable in this area? Can you describe how one measures this?

I was probably just more interested in whether you had any opinions or performed rough calculations on tyre wear between two camber settings and extrapolated out to what an ideal camber setting might be to get the most out of a tyre.
I don't recall seeing anyone else on these platforms having more than -4° front camber - if there was then I missed it.

OptimumG is a wealth of information on suspension setup - they have a six-part introduction, albeit technical at times, to springs and dampers that includes all the formulas you'll need, depending on what information you already have, can measure (or closely approximate) or can find on the forums, it's just a matter of substituting in the values to work out the ride frequencies.
I also reference other sites - they all have the relevant formulas although some are more detailed than others.
There are also books by Milliken, Carroll and others that cover race car dynamics, which include ride frequencies, although, some don't place too much emphasis on it, i.e. it's just a mechanism to gain an extra data point.


I've calculated ride frequencies and revisited it a number of times over the last few years - the last time was about eight months ago - and I'm relatively happy with how my car handles now (quite neutral) but always looking to improve it or adjust for changes in the car, e.g. due to a recent move to different R-comps.

A common thought is that passenger cars have a higher rear ride frequency compared to the front but this is purely to provide comfort - if you plot the front and rear ride frequencies on a graph, the two frequency curves should cross over (or be very close to crossing over) on the x-axis as soon as possible, i.e. being in-phase. I've come across a lot of people who have no doubt read these statements and they extol a higher rear ride frequency than the front - and these people track their cars! Maybe they're more concerned with the drive to and from the track, rather than how the car performs on the track itself.


Race cars aren't built for comfort, therefore, depending on the type of track car, the bias is generally towards a higher front ride frequency since the damper can manage the bumps more effectively due to the dampers having a higher damping rate, which in turn generally support a higher spring rate - your JRZ (as well as Moton, MCS and other high end dampers) are representative of these types of dampers.

Higher spring rates are commonly used on aero cars, which would have even less of an issue with a lower rear frequency (compared to the front) since the downforce generated would also dampen the pitching very quickly so it ends up being in-phase with the front.
Low ride frequencies equate to softer suspension which equals more grip but the trade-off is a lower transient response (braking into a corner, percentage/full throttle near the apex and out of the corner), so, particularly on an aero car, downforce contributes to higher grip and thus the car can be setup with higher ride frequencies.
Similarly for non-aero track cars but at lower, but still relatively high, spring rates and, thus, ride frequencies.

[VictorH]

Interesting thread. I agree the E9x likes a lot of negative camber and I've battled this with my daily driver stree- track car for ages. I run -2.5 degrees neg up front. With that I can get 30,000 to 35,000 miles out of a set of Michelin SS (only used on the street), however at that point the inner tire section is corded and the outside looks new.

I agree with Dogbone, on the track the car likes more negative camber. Just back from AMP and it's tight twisty course and with my camber settings the tire is rolling over to the point of almost reaching the letters (not quite but the little triangles are all gone, on my RE-71Rs). Not as much of a problem at faster tracks, but bottom line we need more camber.

Quick Question maybe for Dogbone since you've run both. I have 60,000 miles on my Ground Control camber plates (the street plates with sealed bearings) and the passenger side is starting to make some knocking noises even though it still feels tight (verified by me and local race shop). Since it's noisy on the street too I'm going to buy a new set. Why are Vorslag plates preferred? I have JRZ RS-sport (double adjust) with hyperco springs. Recommendations would be appreciated.

[dogbone]

Originally Posted by VictorH

Quick Question maybe for Dogbone since you've run both. I have 60,000 miles on my Ground Control camber plates (the street plates with sealed bearings) and the passenger side is starting to make some knocking noises even though it still feels tight (verified by me and local race shop). Since it's noisy on the street too I'm going to buy a new set. Why are Vorslag plates preferred? I have JRZ RS-sport (double adjust) with hyperco springs. Recommendations would be appreciated.

I only used GC Street Plates for a short while. I put them on top of the OEM dampers/springs. They were fine for the couple months I used them on both track and street. But I used them pretty lightly---not many street miles and only a few track days.

A few months later, I decided to go with JRZ RS Pro. I was an early adopter of JRZ for this platform. JRZ didn't have their JRZ-brand camber plates available when I bought my kit. And it was holding the order up. So, they decided to buy me a set of GC Race Plates. All that was installed and I was driving that on both street and track. It was fine for awhile. (At that time, I was not changing camber between street and track. It was fixed at -3.2º and it was killing my street tires quickly.) But then, a mild creaking sound appeared as I turned the steering wheel. After looking at everything else and it being fine, we decided to replace the camber plates and see if that fixed it.

After some looking around, I decided I wanted to try Vorshlag. The Vorshlag has an over-sized bearing that is rated to handle 7500 lbs versus the GC plate that was rated ~4500 lbs. And I liked the overall construction of the Vorshlag better. Both camber plates have funky C-shaped brackets that have the 3 strut top screws welded on. I just liked Vorshlag's implementation better.

We put the Vorshlag in and the creaking went away. I didn't over-analyze the GC Race plates, but the bearing on one of the plates was moving rough/stiff compared to the other one. Nothing looked obviously wrong to the naked eye. Was it just dirty? Was it damaged? Was that stiffness the cause of the creak? I don't know. I put the Vorshlags in, the creaking was gone, and I never looked back.

I have mercilessly POUNDED on the Vorshlag plates for 3+ years now (~60-70 track days) without problems. This includes over 100 camber changes between street and track, as well as surviving multiple suspension disassemblies due to the suspension being pulled off the car for a damper rebuild and several spring changes while experimenting with setup. (I use Eibach.)

My friend has the JRZ-brand plates on an E90 M3, and to be honest, I like my Vorshlag better than those too---especially if you have to change camber all the time. The Vorshlag is a simple matter of loosening the three top bolts and changing camber. Very easy. The JRZ plates have 4 hex bolts in each plate that need to be loosened/tightened. Those darn hex heads strip over time. I have never had an issue like that.

[1MOREMOD]

Yep best out there

[roastbeef]

anyone use any good tools for changing/checking camber?

i was looking at this guy...
https://www.amazon.com/Longacre-7829.../dp/B001NN9G5S

[cherry-m3]

Originally Posted by dogbone

Currently, my E90 M3 is a dedicated, gutted/caged track car with over 100 tracks days on it. But for 3 years, it did dual duty street/track, so I changed camber all the time between track and street. (I have an active build thread over in the Track section of the forum. We talk about all kinds of stuff like this on that thread. I encourage you to check it out: http://www.m3post.com/forums/showthread.php?t=1158445 )

After 6 years of running this car on track, here are my conclusions regarding camber:

-In my opinion, when considering an E9x M3 and tire wear, -2.2º camber is not enough for track use: The tires on the E9x M3 platform benefit from as much camber as you can give them in the front. With running minimal camber in the front (like -2.2º), the car tends to lean over the outside edge of tires and simply destroys the front tire edges very quickly. When I moved to Hankook TD's, which are considered a soft racing tire, I was still running low camber settings. The edges of a 265/35/18 TD would be almost fully destroyed in just two sessions. The rest of the tire looked brand new, but the outside edges were just decimated. I decided to experiment by slamming my camber plates inward to maximum just to see what would happen. The tire edges faired MUCH MUCH better. I could get much more life from tires. And the car drove great. The edges are still the first thing to go, but it takes much longer for them to cord than with less camber. My advice is to have the car aligned with max camber for track use, and then just move to minimum camber for street use. For me, on Vorshlag camber plates and a car that's lower than stock on JRZ, max is around -4º. Your tire edges will thank you. And the car really does feel fine. I have no problem with braking. Turn in feels great. And my tires last a hell of a lot longer than with less camber.

I want to reiterate that my settings aren't a crappy compromise. I didn't increase camber to save tires and then lose performance and just live with it. The car is very fast on track with the settings I use. (This car, with these settings, has won several time attack events and is usually one of the quicker cars out there.) And now that the car never sees the street, and I could use whatever settings I want, I still use the same max camber settings,

-Regarding the potential side effect of toe change when you change camber----I wondered about this so I did a bit of homework. I went to an alignment shop that had a laser rack. I had them do the full alignment based around maximum camber--as far as the plates could shove inward. The camber was around -4º. Once the alignment was done, I asked him to change the camber to it's most minimum setting possible so we could see toe change---basically just pulling the top of the damper as far outward as possible. So, he did that. The minimum camber was around -2.2º. The toe change was VERY minimal. It changed 0.02". So, all the worry of the toe settings changing between street and track is completely overblown. I'm quite sure that very few drivers could detect that toe change. So again, I say get your car aligned with the maximum camber allowed by your camber plates. This will ensure that you're in great shape on track. And then just pull the dampers all the way out to minimum camber for street and the car will drive TOTALLY fine on the street. I did exactly that for several years.

-Regarding bushings----I changed camber settings easily more than 100 times (basically changing before and after each event over the course of 70-80 events), along with driving the car quite hard. I never had any bushing problems.

-OEM Rear camber settings are fine on track. Factory is around -2.2º. I still run that and my rear tire wear is perfect---even on soft racing tires, the wear is even across the tire. No need for super high camber in the back.

-To change camber to max (inward), both front wheels need to be in the air. I couldn't push the damper inward if either front wheel was on the ground. I wanted to change camber at the track so I could save my street tires the stress of driving to and from the track on max camber. This required me bringing two floor jacks. hehe yeah, it's a commitment.

-A fatter tire resists edge wear better than a narrow tire. When you put a fat tire up front, and then use a lot of camber to get that outside edge up, you get longer life from that fat tire because the car can't roll over it as easily. A skinny tire just gets destroyed underneath an E9x M3. When using harder rubber compounds, this tendency is hidden to some extent because the tire compound lasts longer. But when running softer race tire, it becomes apparent after just one session. Of course, max tire width up front is affected by the suspension on the car. I don't know what's possible with Bilsteins.

-If tire life is important to you on track then run a square tire setup and Rotate Rotate Rotate all around the car. Running staggered can be nice, but it limits your ability to rotate. Rotating tires is a bit of a pain, but sharing the stress by rotating makes them last quite a bit longer. With the softer tires that I run now, I never go more than 2 sessions without rotating. With a harder rubber compound, I know people will run a whole day with the tires in the same position. I would still recommend rotating once in a day if possible. I know it's not fun.

So, to recap: get an alignment with max camber. Change back to minimum camber for street driving to save the inner edges of your street tires. Have fun!----except when rotating tires.

LISTEN TO THIS MAN.

Thanks for the advice. I just came back from Watkins Glen and inspected my front wheels and noticed i was wearing the outside edges and rolling over on the sidewall. I adjusted my kws in as much as possible and the problem still persisted but not the to extent as my earlier sessions (went in at -2.1). I noticed the front likes to do a crab walk when the tire is riding on the sidewall like that.

The toe change is also great to know. Thanks for the info.

[bigjae1976]

Originally Posted by roastbeef

anyone use any good tools for changing/checking camber?

i was looking at this guy...
https://www.amazon.com/Longacre-7829.../dp/B001NN9G5S

Should be fine as long as the magnetic base fits through the wheel center bore. Otherwise the magnet is useless.

I got a $15 gauge from eBay. I need to modify it since it does t fit through the center bore. It's basically a bubble level with a magnet base which is good enough for me unless I need to get accuracy beyond .25 degrees.

[dogbone]

Originally Posted by cherry-m3

LISTEN TO THIS MAN.

Thanks for the advice. I just came back from Watkins Glen and inspected my front wheels and noticed i was wearing the outside edges and rolling over on the sidewall. I adjusted my kws in as much as possible and the problem still persisted but not the to extent as my earlier sessions (went in at -2.1). I noticed the front likes to do a crab walk when the tire is riding on the sidewall like that.

The toe change is also great to know. Thanks for the info.

Glad to hear you tried it and that it's helping!

[roastbeef]

i think i'm going to try that next... just loosen them up and shove them all the way in? easy enough to try.

[dogbone]

Originally Posted by roastbeef

i think i'm going to try that next... just loosen them up and shove them all the way in? easy enough to try.

Max on track. Minimum on street. Done.

In my opinion, going through the trouble of buying a gauge to measure camber will only give you a rough measurement. I mean, where would you try to set the camber?---While the car is sitting on some random pavement in a paddock? Good luck finding some level ground!

[roastbeef]

yea, you're right. i guess it is relative to how flat the car is sitting.... i didn't really think of that.

i don't suppose there is any worry about the max and minimum settings being slightly off from each other?