Actual alignment specs from BRZ
 

I got my car on the alignment rack today and got the factory set specs. There is a distinct lack of -camber up front and and the "right" amount in the r/r only. I'm guessing that the difference from the l/r is somehow supposed to counter road crown.

I'm surprised how much my weight affects the static alignment specs. The top printout is from the car empty and the bottom with me in it. I'll be using either concentric bolts or plates to get camber adjustment in the fronts, and will equal out the rear. I prefer zero cross/camber and zero cross caster, both front and rear, with zero toe in front and a touch of toe-in in the rear for braking stability.

Input on this subject is appreciated

Attachment 8080

The actual numbers don't mean anything to me, but after driving a fair bit on the highway tonight, I see what @Ryephile meant about having to work to keep the car in its lane. It's incredibly eager to change direction, but it seems there's a trade-off in highway driving. Would a small change to camber or toe help make it feel a little more centered?

Yeah, the frontal toe out may make it more twitchy at high speeds. Generally this should be 0 for stability and minimal wear.

It blows my mind that they would have 0 or even positive camber in this thing up front with a MacPherson strut design. I'm sure there was some reason but that's hard to justify. So adding negative camber may help cornering stability as well.

BTW taos, are you able to corner weight this thing with you in the driver's seat?

No access to scales. I think somewhere on here I've seen the corner weights posted. Of course in order to corner "balance" the car you need some sort of ride height adjustment (coilovers)

Yeah, I've seen corner weights without the driver before but was curious how it would distribute with a driver. Oh well. Thanks a lot for the specs.

From looking at those pictures, i'm curious why the passenger rear has so much more negative camber than every other wheel.

I've got some inquiries out to see if anyone is developing a camber plate. I will be checking to see if the old Noltec camber/caster plates I have on my wagon will fit. I remember reading somewhere that the top hats are the same parts # as Impreza, but haven't been able to find it.

Still searching, guess I'll find out for myself if I can get a rain free evening to work on it.

Looks like there's not much interest in this subject, but I'll keep posting anyway. Part # for the BRZ front strut mount (top) is 20320AA111 which comes up in online part searches as the mount for Impreza and Forester, including WRX. This tells me that camber/caster plates already made will fit the BRZ.

Why am I so interested to know this ? Well.....automakers engineer initial understeer tendencies into all new cars so that the "average" driver doesn't get into trouble in slippery situations. Push, as it's known, is not exactly the fastest way to turn in.

While the BRZ doesn't under steer as much as say, a WRX or any other AWD car, it does "push" at turn in. Being rear wheel drive, it rotates much easier with throttle application, but this doesn't allow carrying as much speed into corner entry.

From looking at the stock alignment specs, it's apparent that the BRZ engineer's solution to create under steer is to eliminate negative camber up front (no concentric adjustment) By adding negative camber up front the outside tire will maintain a larger contact patch at turn in thus achieving more grip, curing the under steer.

Concentric bolts first and then camber/ caster plates with a proper alignment will be my first mods to the suspension.

I've not messed with suspension changes much on my vehicles (seems like something of a black art), but I did put camber plates (-1.25°) on my MINI and they made a huge difference. On that car, most people tended toward using a stiffer rear swaybar to get rid of understeer, but it seems like that really just adds oversteer: it doesn't help the front grip any better. I added them because I was trying to improve tire wear on track days. The result for me was much more eager turn-in and better grip, but at the expense of more torque steer and a tendency to want to change direction when on rutted pavement. I have to work a little harder to keep the car pointed in a straight line on the highway, but nowhere near as much as I do with the BRZ stock.

Will you be focusing on adjusting camber up front, or out back, too?

We're doing another run of our RCE Lowering Camber plates. More camber and lower the car 3/8th of an inch without sacrificing bump travel. Boom.

Right now we're running the Whiteline Com-C strut top mounts which add some camber and caster in a hardened rubber mount. Great street solution.

The bolts are a must have for every car IMO regardless of whether or not you're gonna run plates too. First thing everyone should do.

- Andrew

actually a very tiny amount of toe-in will help stabalize the car since each wheel will work to center the car.

very very very tiny amount, but not dead set on zero


also to everyone out there, always do your alignments with you in the car.

Figured I'd post this up in this forum as well, since some folks may not see it in the track/autocross forum:

http://www.ft86club.com/forums/showp...8&postcount=75

FYI, this was with the car empty. It wouldn't have changed the approach to the camber anyway and I expect I'll be tweaking the toe after some autocross testing in the near future.

I have the concentric bolt part # at 20540AA090. I'm not going to get a chance to do anything on this until our afternoon rains subside and I'm going to Wicked Big Meet this weekend. My BRZ will displayed at the Grimmspeed booth :w00t:

I'll get the bolts in and do a new alignment Mon.

Thanks, when will you have your plates available ? Will they work with the stock struts, or coilovers only ? I'm familiar with the Whiteline bits, but I prefer the adjust-ablility.