ragtophardtop

I've never gotten an alignment before and there's too much info for me to really understand a good choice. The car will be a weekend cruiser that will periodically partake in AutoX. I'm looking for max steering feel and quick turn in and neutral feel, but most miles are put on with weekend long-distance cruising, so I'm trying to minimize camber and toe wear. Some wear is fine, but not aggressive toe wear. Can anyone with experience comment if this alignment is going to be what I'm looking for? I searched threads here on the forum and robrobinette's website, but there wasn't a consensus for this type of alignment. I come from the miata world, where this type of driving purpose would typically require 1/32 toe in in the front.

Front:
Camber 1.3 degrees
Caster max
Toe 0 degrees

Rear
Camber 1.7 degrees
Toe .20in toe in 0.15° total toe-in, 0.075° per side

B serious

^That is a good place to start

ZDan

I would run a lot less rear toe-in. 0.20 in. is nearly 0.5°, that will hurt turn-in, wear rear tires out quickly, and can cause the car to hunt or move around over asymmetric bumps/undulations in the road. I'd keep rear toe ~0.10° to 0.20° total (or 0.043 in. to 0.086 inch total)

ragtophardtop

Interesting. So what is the toe in designed for then if it has both these effects? I understand toe changes as the suspension loads in corners. So what's the difference between ~0.10° to 0.20° toe?

B serious

More positive rear toe really just means that the back of the car stays "centered" because both the wheels steer toward center. More + rear toe means more understeer and more straight line stability.

My assumption was that you meant 0.20 DEGREES TOTAL. Not inches or per side.


.20 inches total is a lot...but would provide a lot of stability/understeer. I believe its still within AP2 spec?

0.13 (1/8) inch total is probably better.

Have you tried autocrossing with a good stock alignment first? If not...how can you know what you want?

ZDan

The alignment spec is a very broad range. You were aiming at (maybe beyond?) the maximum end of the specified range. I strongly recommend running closer to the minimum end...

More rear toe-in is often touted as making a car's rear end more stable, but in my experience running a lot of rear toe-in at the max end of spec sucks pretty bad for everything, and can make the car *less* stable in a straight line while also inhibiting turn-in responsiveness. All while cutting tire life in half...

Rear toe change with bump is an AP1 thing. They fixed the rear geometry with the AP2 so it handles a lot more linearly. But either way IMO better to run minimal rear toe-in.

I think the spec AP2 range is 0.12° to 0.44° total. I recommend running at the very low end, up to no more than about 0.20° total.

ragtophardtop

I'm not looking for a lot of stability or understeer. I'm looking for very neutral handling, I just don't know how to express it in alignment settings. My current alignment is stock and I don't like it, the lack of steering feel sucks. Alignments are $120-180 where I'm at for a decent shop so I don't want to screw around with a stock alignment first and then just have to do for another one.

I'll be changing my toe spec in my original post to 0.12°, as both you and B serious indicate the low end is better. I'm assuming this is toe in, is that correct? Is there much difference between this and 0.15°?

ZDan

Toe IN, that's correct.
You would not be able to tell the difference between 0.12° and 0.15° total toe-in, neither would I...
Again, that's *total* toe-in, half that per side.
For stock 24.7" diameter tire, 0.12° = 0.052 in. = 1.3mm = 0° 7' (arc-minutes)

HappyFunNiceGuy

I'm new to autocross and this is what i'm running right now with stock AP2 on 08 shock/springs. I did my first 6 events this year on the stock alignment.

In degrees:

Front

Caster left: 6.4
Caster right: 6.4

Camber left: -1.8
Camber right: -1.8

Toe left: 0.1
Toe right: 0.1
Total toe: 0.2

Rear

Camber left: -2.5
Camber right: -2.5

Toe left: 0.2
Toe right: 0:2
Total toe: 0.4

I'm on a 225/255 setup on re71r tires and I daily drive my car. So far i'm pretty happy but I have no idea how this setup will last long term as this is my first non-OEM alignment. I figured I can adjust from here if needed but also haven't found any definitive information on what is best for a daily/auto-x mix.

ragtophardtop

Are your toe figures positive or negative? Does the car feel neutral?