Roadracing7

iTrader: (2)

I have 245/35/18 f and 285/35/18 rears with +45 and +42 offset respectively. The car is out of the paint shop and going to the alignment shop. I've got apex'i N1 coilovers and setting up about 1/2" tire/fender clearance front and 5/8" tire/fender clearance rear. What specs should I shoot for it the car is mainly for daily driving and occasional autox?

Camber?
Caster?
Toe?

Thanks,

Richard

rynberg

The proper rear tire size would be 285/30, not 285/35. Your height should be adjusted from a base line to corner weight the car. Since your car is street-driven, I would start at a base height of 25.5" inches from ground to top of fender well, at all four corners. You do NOT want the rear significantly higher than the front unless you like high-speed oversteer.

I like to run modified Pettit Long Track specs:

for 18" wheels:

front:
camber - -1.0 to -1.2 deg
toe - 1/16" in
caster - 6-7 deg

rear:
camber - -0.5 to -1.0 deg
toe - 0 to 1/16" in
thrust angle: zero

This will give you good response without negatively effecting straightline stability or tire life.

Roadracing7

iTrader: (2)

Thanks Rynberg, somehow I knew you'd respond. I'm finally gonna get my car back... Thanks again for the help! I don't mind high speed oversteer either... We used to set up the Formula Mazdas to hit the bump rubber and be flat from turn in, so I'm used to chasing the back end. Not that I want it THAT much for street driving, but a little bit will work. And you're right, they'er 285/30s... It's been so long since I've even seen the tires! Thanks again.

Roadracing7

iTrader: (2)

one question, why toe in on the front?? not 1/16" out?

DamonB

No need for toe out when road racing. I run toe out but my car is primarily autox'd and the toe out helps with the much smaller turning radiuses of an autox course. On a road course you really don't need toe out. If an FD needs toe out to turn in on a road course it's got bigger setup issues.

My current alignment is strictly for race tires though I do daily drive the car. That means I eat street tires much faster than I should (I got about 12K out of my last set of Kumho MX tires). For road course use I run lower cold pressures than I do for autox and I typically run the front bar stiffer and the rear shocks softer. If I was willing to always re-align the car I'd run toe in rather than toe out on the front and I wouldn't be suprised if I ended up with less negative camber on both ends of the car as well.

Front has 2 degrees of negative camber with 1/16" of toe out. I forget what caster is at but it's maxed for my camber setting. I think it's just under 4 degrees.

Rear has 1.8 degrees of negative camber with 1/8" of toe in.

Car is on stock springs and Koni yellows. Stock rear '93 bar and a Tripoint front bar run at the middle setting (third hole). The front shocks stay at full hard unless it's especially slippery. The rear shocks are run as stiff as surface grip will allow, usually anywhere from a half turn to a full turn from full soft.

rynberg

Just thought I'd point out that Damon's camber settings are with 16" tires. 18" tires should not need that much camber. Additionally, those camber/toe settings will result in accelerated tire wear in street use, especially with 18" tires (as Damon pointed out).

DamonB

Thanks. Stock 16x8 wheels.

vel525

iTrader: (4)

Quick question about where to get aligmentdone. Is it bad to go to a pep boys to get your alignment done? Or does it not matter as long as you tell them what camber, toe, and caster.

Mahjik

iTrader: (1)

Some places won't do custom settings. I always have mine done at Goodyear. The one near me has ramps to get lowered cars up onto their rack, and they never give you crap about the settings you want.

I think it's just going to depend on the shop as other Goodyears in my area are the same, so it's going to be the same with any other shop. Just talk to them, see if they can get your car onto their rack and then see if they'll do your settings that you want without hassles.

alberto_mg

and always get a printout after they do it so you know which settings the sometimes lazy mechanic actually set the car at. make sure to tell them in advance that you want a print out and have them write it down on the form. i've gotten a few bad alignments in the past...

vel525

iTrader: (4)

mahjik, alberto_mg thanks guys.