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240GURL
01-22-2003, 03:05 PM
What is the difference between a regular alignment and having your car aligned for autocrossing?

And more importantly, if I take it to Midas or the dealership and I ask them to align it for autocrossing, will they know how to do it right?

Thanks, just trying to get all my ducks in a row before next season starts!

bbp
01-22-2003, 03:12 PM
A typical autocross alignment would consist of roughly 1/16 to -1/8in toe out in the front and 1/16 to 1/8 toe out in the rear.

Midas or the dealer may question you on this because it could cause premature tire wear.

240GURL
01-22-2003, 03:36 PM
So basically if I have it aligned that way, I would want to take it back and have it aligned normally after the autocross, right?

bbp
01-22-2003, 03:43 PM
naw, i'd just leave it. it's not that bad, they may just give you a hard time about not doing what their books tell ya.

Ask around see what some others are doing, see if they have any other customers that autocross.

OR get a tape measure, measure the front of the tire as high up on the tire as possible, then measure the back using the same tread at an equal distance up the tire. Subtract the diffrence, that will be your toe. If the front is wider than the rear of the tire you have toe out and vice versa. It is easily adjusted. You may try to check it your self before you spend the money, just to see what it is. it may not need adjusting.

Also, if you have never autocrossed, or do not do it often, I wouldnt worry too much about your toe, unless your alignment is way out of whack to begin with.

adey
01-22-2003, 08:08 PM
If you have coilovers or pillowball mounts (which, just by reading the above posts, I doubt) or any other way to adjust your front camber, you may also want to dial in a degree or two of negative camber for increased traction while taking the turns.

Both Toe out and negative camber (as opposed to toe-in/0-toe and positive camber/0-camber) will cause increased wear on the inside of your tires, toe having the greater effect of the two. As alignments can be pricey (I pay ~$40 for a 4-wheel alignment to my specs), you may consider getting it aligned once and not worrying about (too much) it thereafter. For a good combination of street/Autox, maybe 0 toe (doable) and a slight amount of negative camber (which, incidentally, is not adjustable up front unless you have aftermarket pieces) in the front and 0 toe and +/- 0 degrees of camber in the rear.

Those are just some numbers you might consider using for reference... FWIW I run about -2.5 degrees of camber up front and about 20-30 minutes of toe out up front (0 camber and 0 toe rear-- because the guys who did my alignmnet didn't realize I have slightly adjustable rear camber) on my 240, which I take road racing for a few hot laps every month or two.

LanceS13
01-23-2003, 09:14 AM
I run zero toe all around for a decent compramise between low speed rotation and high speed stability (and less tire wear). Camber is -1.7 front and too excessive to mention in the rear. If I had adequate adjustment, I'd probably run between -1 and -1.2

bbp, what alignment do you usually run on your racecar?

bbp
01-23-2003, 09:28 AM
it really depends on what my tire temps are telling me and what track. For the most part, toe what I mentioned above, if it is a high speed track I will dial in 0 rear toe.

Camber is determined solely on tire temps, I may have 2 degrees neg on one side and 2.8 on the other. I just keep adjusting it until the temps look good.

Three indispensible tools, tire pyrometer (probe type), pressure gauge and tape measure.

LanceS13
01-23-2003, 09:51 AM
I shoulda known it's never the same...what was I thinking? :p
What kind of rear camber adjustment do you use?

bbp
01-23-2003, 09:57 AM
whiteline eccentric bushings. I dont adjust that ever. I dont rmember off the top of my head what it is set at, have to look at my notes. GC camber plates up front.

240GURL
01-23-2003, 03:00 PM
Good advice, everyone! I'll do the tire measure thing and see what I come up with. Thanks for all help!

MovinUp-1
01-23-2003, 04:06 PM
I know that my friends that race corvettes usually run about .5 degree negative camber in the rear. If your car is a daily driver and once a month autocrosser I would suggest a zero toe so that it doesn't feel darty on the highway. As bhp suggested, set your front camber by tire temps. If you're getting into autocross this much I'm sure some of the people you race with would be willing to help at a test n tune day.

Allen