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Getting my car aligned by Mark tomorrow and was curious as to what some of the veteran front drive guys recommend as far as caster, camber and toe on a slightly lowered FWD car.

Depends on how it's handling now and how you want it to handle. Do you know your current specs?

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I would say, as a general rule, to go for max negative camber in the front, up to about -2.5 degrees. I could just get that in the Neon- on the Mini we get only -0.4. For front toe, it depends a bit on your steering geometry, some cars toe in under acceleration, some toe out. For autocrossing in the Neon we went with zero toe or slightly toed out for quicker steering response - makes it darty on the road, though. I don't recall offhand what we're doing in the Mini- my guess is zero toe.

At the rear we went 0 and 0 for both the Neon and the Mini- if your car pushes badly you might want to try a little toe out. Generally FWD cars do not want negative camber in the rear.

Hope that helps.

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Carl Fisher

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Jeb,
We have a total toe out in front of -1/16. The Mini doesn't have a camber adjustment so we're with factory on that. Rear toe is 0. Just remember, Carl's right-too much toe makes the car a little twitchie on the street. Also eats tires for daily driving.

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This will be for daily driving as well. Despite where I work, I don't need to eat up tires. The car seems to handle pretty well. I am hoping to reduce some of the oversteer I get from the bigger rear bar. Any throttle lift and the car is overly eager to rotate.

I can't seem to get a chart or table to work here so here is a link to the thread I posted my specs in on the mazda board. You should be able to view it without registering. If not let me know and I will post a screen shot of that post...

http://www.mazda3forums.com/index.php?t ... msg1443669

What spec are you currently running?

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02 Focus SVT
STF 9

Did you click the link? My actuals are listed for all four corners.

I suck at the intarweb....

Ok, if I read it right, you have a smidge of toe out in the rear. I might would try Zeroing that out.

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02 Focus SVT
STF 9

I don't know much about Mazda3's but if someone put a gun to my head and told me to align one for autocross, I would go with -2.5F, -1.5R, 0 toe all around.

In a car with a fully adjustable suspension, don't use the alignment to "cure" and handling ills with the chassis. The goal is to use the tire optimally. Tune handling with springs, shocks, and sways to achieve near-balance. Then set tire pressures to get a flat temp curve across the tire. THEN go back and change camber based on what tire temp measurements tell you to do.

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

My specs:
-3,-2.5 F/R camber
3 F caster <-- I'll be adding more of this next week, trying to get ~5
1/8 out, 0 F/R toe

I'd have to agree and disagree with Mike in that you want to optimize the front end but the rear should be used to tune the balance. This is for FWD *only* but the approach I use is to get as much front grip as possible and then toss away (or add) rear grip until the car is balanced nicely. That usually means that the rear is far from "optimal" but we are just dragging those tires around anyway.

I also don't believe that you should shoot for even temps across the face of the tires due to the fact that they cool off so quickly. Unless you have some way of measuring temps dynamically, I'd look for the inside edge to run several degrees hotter than the middle with the outer edge being the coolest. Can --> Worms --> Danger!

Jim

Agree and disagree

Back in my Honda Challenge racing days, the cars were tuned the same as RWD -- with springs. If the car was pushing, add rear spring rate, don't throw away grip with camber or pressure. (for those watching at home, remember that adding rear spring actually INCREASES front grip). In a totally developed FWD race car, I have to believe they have camber and pressure set for optimal grip at all 4 corners.

But the point I was making is -- in a class with suspension allowances, you don't have to deo stupid stock class tricks to get a car to rotate. You're allowed to make changes to actually use more of the tire and balance the car with parts.

Just because a Mini wants zero camber in the back doesn't mean it's optimal. It's a band-aid



Fair enough. But it's better than nothing! I ran a skidpad at Laurinburg a few years back -- drove in a circle until I was dizzy then jumped out and IRed the tire. Not optimal but I learned a lot from the experiment. I learned what was too much pressure, too little, whether the car was balanced, and that 2.5 degrees camber up front was not enough on an E30.

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

I totally agree with that. My point that I didn't make very well was that we can't tune for an optimal setup in an AutoX environment since it changes every time we show up. Add surface/weather changes to the mix and you are chasing your tail.

Get the car as close to balanced as you can under "typical" conditions and then you can use "stupid stock class tricks" at the event to fine-tune for the actual conditions.

That is actually the topic of a thread I've been thinking of starting. What can be done to minimize the variance in how a car responds to different conditions?

Jeb, if you're worried about tire wear on the street, get Mark to show you how much you need to turn a front tie-rod to give yourself a little toe-out in the front and then have him set it near zero. That's what I do and it takes me less than a minute to make the change at the event. I managed to get 20k miles with ~400 runs on a set of full-tread Azenis 215's my first year with the car doing that. Granted, the tires were *done* after that and I probably should have replaced them at ~16k miles when they hit the wear bars but I was still impressed.

Jim

I would agree with Ryan's rear toe comment. I had initially run my car with a small amount of toe out and with the larger rear bar it did cause the same problems you are having. I went to zero rear toe and it really helped to solve that problem.

I also like Jim's idea of running zero toe in front, but knowing what to do to adjust to having some toe out at events. I ran with about 1/8" toe out all of the time and I did have wear issues. If I wasn't so lazy, I might have done as Jim suggests myself.

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I've tried all the stupid stock class stuff on my 2.5RS with non-optimal suspension setups & I've tried actually setting it up right (the way Hoppe told me to do it). Raising the rear spring rate from 350 to 400 did a LOT more for proper rotation than increasing the rear tire pressure by 20psi, or by going to 3/4" toe-out in the rear. If you don't have the right suspension setup (springs & damping), all that little crap you can do to "fine-tune" it is pointless.

Just remember to take a step back and view the reality of your situation periodically, instead of getting too caught up in alignments, etc. If your last name is not Feinberg or Peterson or some such nonsense, you're probably wasting your time if you're not just focusing on your driving.

understood. Part of the reason I am doing this is that I need an alignment. Ever since the shocks have gone on the front end is off. I usually have to have the steering wheel slightly turned to keep the car straight. That wasn't an issue before. So I figured in light of that, I could kill two birds with one stone and get an alignment that would not kill tires on the street and maybe benefit the car's handling when autocrossing.