How does my alignment look?

[b_w.]

got the car back from alignment last week. Curious what the group thinks. Street is on top, track on bottom. This is on the GTMORE setup. Instructions I gave the shop were SYT's alignment instructions.

I havent tried the track setting yet but hope to this weekend. One thing I notice so far on the street setting is the car feels a little more squirrely under acceleration. I am now running 315's in the front vs 275's on the old setup so I feel road imperfections more for sure but even on smooth roads it feels like it is moving around. All rubber is out and replaced with heims. One thing I notice on the alignment is that street camber is now at -1.4 degrees where it was -1.9 degrees before.



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Here is my old alignment from the MCS2WNR and GC Camber Plates. This felt great in both street and track settings.



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[drroc]

You could go for 0 degree toe to help the turn in.

[dzxy]

Weird how you're feeling less stability with your current setting as you now have more front toe in at street setting and same rear toe when compared with your old setup but i guess that could be attributed to running some fat tires in the front lol/

As for your front camber change at street setting, my guess is that your suspension geometry in the front changed with your new setup in such a way that to obtain your target street front toe value, the resulting negative camber value was decreased. The shop probably prioritized your track setting, so somehow your geometry required you do decrease negative camber from track setting more in order to hit that toe. My guess is the SPL toe arms.

[M3SQRD]

The very wide front tires are tramlining by finding any and all road surface imperfections as well as the crown of the road. Additionally, if these are brand new tires, you’ll have lower grip due to the mold release used during manufacture of the tires. With 315 front tires and a small amount of toe-in the former is likely to occur frequently. Switching to your track alignment setting will only make this worse due to the unstable toe-out which will make tramlining worse. I had this issue with 275 square setup on my e46 M3 dedicated-track car when driving to track events. One thing to look forward to is a sharp front end on track!

Your street settings are very conservative. Camber at -1.4 deg (or -1.9 deg) is factory camber range. I’d run at least -2.25 to -2.5 deg. Camber doesn’t cause excessive wear, it’s toe that can destroy a tire in a few thousand miles. 8.1-8.2 deg of caster should work well on track but could be contributing to the tramlining and/or darting on the street. 0.40 deg of toe-in is will give you a little bit of stability but i prefer to run 0.0 deg on the street. As for the rear, -2.0 deg of camber is fine for the street so is 0.18 to 0.19 deg of toe-in is on the low end for a street setup. Any idea why the street settings are slightly lower than track settings?

As for your track settings, -3.0 deg is not going to be enough for a sticky 315 mm tire. Which brand and model is the 315 mm tire? My guess, based on my e46 M3 setups, you’ll need a min of -3.5 deg of camber. I actually ended up at almost -4.0 deg. However, the f8x has a better/stable camber curve compared to a e46. You lost a little caster going to the track setup but it’s still at least 8.0 deg of caster. Dynamic camber gain requires a lot of steering angle so i hope you’re not using that to reduce your static camber because in higher speed corners with less steering angle won’t give you the total camber you’ll need. -0.2 deg of toe-out will help to turn-in that massive 315 mm tire which doesn’t want to turn/change direction easily. Sometimes a wider tire can hurt your turn-in on every corner so a less wide tire can be faster because it wants to change direction more easily which decreases lap times. For the rear, -2.0 deg of camber is a good starting point. I prefer to not run over -2.25 on the rear because that’s at the point where you’re trading cornering vs. putting the power/torque to the ground. Toe-in of 0.20 deg should be fine but I’ve never used a 315 mm tire so not sure how much stability you’ll have midcorner.

When you adjust your front camber from -1.4, or -1.9, deg of camber to -3.0 deg, does the toe settings go from +0.40 deg to -0.20 deg?

Edit: I misread the toe alignment angles. I thought it was degrees, not in DMS.

[Track/S]

If you felt great with the old alignment do you think such an aggressive alignment is necessary?
The instability is due to the wide front tires, at high speeds with that alignment the car is much more stable

[N1rve]

Ideally you want more negative camber in the front than the rear because during a turn the negative camber essentially becomes neutral in the front once it loads up which maximizes the contact patch during a corner hence better grip in a corner.

Something like -3.5 Front and -2 Rear should be a good starting point.

You don't want something like -2 Front and like -3.5 in the rear. This will result in understeer.

Quicker Turn In = Toe Out
More Stability = Toe In

If you need a more stable alignment, it would be like 0 toe front and a slight toe in for the rear.