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      12-07-2019, 03:58 PM   #1
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Changing my camber at autocross

So Iím running tc Kline camber plates. Running as a daily driver at -2.00 front and rear camber. Toe at zero front and rear. Car handles good on street, no issues. Also at autocross a few events it felt fine at this setting. However, I can adjust the camber settings when I change over my tires (I run apex 10inch wides with re71rís 285/30r18 square set up at autocross). So since car gets jacked up I could easily go to -2.75 front for events and then go back to -2 afterwards. What will this do to my handling? I know toe will be affected slightly but in autocross probably not enough to care about. Does anyone know?
I can also go to -2.75 and then back for an alignment and then just keep it at -2.75 for daily driving at zero toe as that doesnít seem like too crazy of camber for a daily.
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      12-13-2019, 02:44 AM   #2
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Wish I could tell you exactly how much toe out you would get from changing camber from -2.0 to -2.75, but haven't changed mine by such a small amount. If I were to guess, maybe 1/8" total toe out with the change. Quite a bit for autocross, but not undriveable. Depending how many miles a year you drive, I would go with the -2.75 camber as daily, with zero toe. Either that or run -2.0 daily with 1/16" toe in, then bump the camber to -2.75 at the autocross only, and autocross toe should be acceptable. Just my estimate. I run -3.0 camber daily, zero toe, but only drive 5k miles a year, so tires will age out before wear out.
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      12-13-2019, 10:45 AM   #3
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Hereís a dumb question, would changing rims/tires change the camber? At first I thought it would never affect camber but the two alignment shops I took car too had two very different camber readings and the only thing I changed was my tires/rims. One shop said -2.0 (dealership, and on my winter tires/rims) and another shop previously said itís at -2.6 (summer 265/285 pss on stock rims)
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      12-13-2019, 10:46 AM   #4
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And the tc Kline plates cannot change camber like some of the other ones that can slide.
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      12-13-2019, 04:39 PM   #5
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Tires should not have an impact on camber, especially not that drastic. Sounds to me like one (or both) of the shops alignment racks need calibrating. If you really want to figure out how much changing your camber from -2 to -2.75, do some math. They sell toe plates that you use 2 tape measure-ers for. Idk the specific math to get an actual degree, but it shouldn't be too hard. Or just know that if you're at the same measurement front to rear of the tire, and then you adjust camber you are now reading 1/8" difference (or whatever), then you know you have SOME amount of toe in or out.

Now that I think about it, download an 'angle measuring' app on your phone. Get a straight edge and put across the FACE of the wheel (to avoid any irregularities with the lips on the tire) and then place your phone on it. It should give you some reading, perhaps you can decide whose machine is more accurate based off what your phone tells you. A couple of my drift buddies use this trackside for rough measurements and mirroring camber/toe from one side to another. Could definitely give it a shot.
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      12-13-2019, 04:54 PM   #6
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Iíll try measuring camber manually. Youíve given me several ideas to manually do it. At least confirm which guy is more accurately measuring it. I would think the dealership rack is most accurate and calibrated but I guess itís only as good as the guy attaching the reflectors to the rims.
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      12-14-2019, 03:11 AM   #7
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I agree that tires and wheels alone should not result in that amount of camber variation. Camber can change from certain effects, such as ride height, steering wheel not straight, sway bars that bind slightly. For example, a shop doing an alignment jacks up the front, then drops back down, if sway bars or other suspension pivot points bind a bit, the car may not fully "settle" down, resulting in a lower camber reading (less camber). Same if one shop has you sit in the car, or maybe you had a full tank of gas, or just more weight in the car, all could contribute to more compression at the suspension and thus more negative camber. Just throwing out ideas. My stock springs M2 currently has 1.7 deg neg camber (with the knuckles), not much, am hoping with more miles the springs sag a bit and the camber will increase. Maybe wishful, eh?
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      12-14-2019, 10:57 AM   #8
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Go to an alignment shop that can set both street and track/auto x camber.

Your street alignment looks fine, and depending on your (200 wear) tires around 2.9-3.1 would be a great place to have your auto x setting marked on your plates. If you're running Hoosier A7's then even more camber will be needed. 3.4-3.6 . This is assuming you have a good aftermarket C/O setup with linear springs.

When you prep your car for the day move the plates to the auto x setting...

Don't worry about the toe change.

I've done this with several cars over the last 20+ yrs.

If someone tries to tell you the toe change is important to address I'll disagree with them. I won several years worth of 1st place BMW & SCCA Solo 2 trophies in 4 different classes using this method (ASP, BSP, ESP, SM)

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      12-14-2019, 01:27 PM   #9
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Thanks, good info. I did happen to have 100 lbs in trunk for winter driving at last alignment. So that does cause rear to squat a bit. So definitely not apples to apples.
Iíll wait until summer and the get another alignment at closer to -2.75 front (tc klines are supposed to be 0.75 per hole on the adjuster). In summer I use pss 265/285r35 on street and square 285/30r18 re71rís on apex 10 inch rims for autocrossing. Right now running 255/35r19 blizzaks on some stock looking knockoff rims square.
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      12-14-2019, 01:31 PM   #10
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Iím on stock shocks and springs. For a daily I didnít want lowered nor any rougher ride, potholes and curb clearance issues at the house. I still might change to a set of coils in future if I can find some ÷hlins take offs and tune them for compliant ride. I can rebuild shocks myself from quad and sled experience. If I drop it 1/2 inch would be max Iíd go, that would also add more neg camber.
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      12-14-2019, 04:50 PM   #11
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The stock springs are progressive ones. They suck for any serious cone carving or track days. The idea of a good C/O setup is to get a package setup with the proper linear springs.

If you're on RE71R's I bet you hit the bump stops when loading the suspension in tighter corners. Probably almost picking up the inside back wheel as well.

A well setup C/O kit will still give you a decent ride on the street. Double adj Koni's or Ohlins R&T are two of the best bang for your buck kits IMHO.

Otherwise your going to be up in over $4K easily. Moton's, JRX's, MCS's, Penske's, are easily $5K for Double's...

Bottom line is how far do you want to go to go faster (putting aside your own driving skills)
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      12-14-2019, 11:29 PM   #12
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I also have to balance the fact that the car will get switched out in a few years with something else due to daily driving. I rack up the miles.
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