Alignment Help Thread

[Burt]

Originally Posted by 3rdGenAg2010

Pete. Thanks so you think about my alignment I posted above for autocross?

My car sees fairly regular autox and quite a few mixed street miles, and I'm running the following:

Front camber: -2.5
Front toe: 0.05 out each side

Rear camber: -1.4
Rear toe: 0.05 in each side

I could get more agressive with the toe settings, but so far this has worked really well for me. Tire wear has been perfectly even as far as I can tell, the car has good grip balance for autox but is still pretty stable on the highway, even in the rain.

[JusticePete]

Originally Posted by Burt

My car sees fairly regular autox and quite a few mixed street miles, and I'm running the following:

Front camber: -2.5
Front toe: 0.05 out each side

Rear camber: -1.4
Rear toe: 0.05 in each side

I could get more agressive with the toe settings, but so far this has worked really well for me. Tire wear has been perfectly even as far as I can tell, the car has good grip balance for autox but is still pretty stable on the highway, even in the rain.

[3rdGenAg2010]

Well i guess the alignment was good enough to win F street!

[3rdGenAg2010]

Went to my second Autocross event, and in this course the car seemed to understeer. My alignment sheet is a page back.. Would reducing the rear camber to -0.5 help increase oversteer? Thoughts?

Also, does anyone have an alignment shop in houston that isnt dumb and tell me that the camber on the front isnt adjustable?

Thanks!!

[KillboyPowerhead]

Can you measure tire temps? This would let you know if you could use more or less camber. What else have you done on the car? Sway bar sizes? Spring rates? Tire sizes?

[Burt]

Originally Posted by 3rdGenAg2010

Went to my second Autocross event, and in this course the car seemed to understeer. My alignment sheet is a page back.. Would reducing the rear camber to -0.5 help increase oversteer? Thoughts?

Also, does anyone have an alignment shop in houston that isnt dumb and tell me that the camber on the front isnt adjustable?

Thanks!!

We're you at the same lot as the first event? One thing I've run into is the widely varying grip at different lots, and changing to a low grip lot makes it much easier to overdrive the car and make it push. I've even been to the same lot two weekends in a row, and some rain before the second event cleaned the track and brought some residues to the surface, and it actually had less grip than the week before.

[3rdGenAg2010]

Originally Posted by KillboyPowerhead

Can you measure tire temps? This would let you know if you could use more or less camber. What else have you done on the car? Sway bar sizes? Spring rates? Tire sizes?

I dont have a way to measure tire temps. The pressures rose quite a bit, and next time im going to lower them back to my start up pressures of 38psi front 36psi rear. car is 100% stock. tires are 285/35R20 all the way around.

[3rdGenAg2010]

Originally Posted by Burt

We're you at the same lot as the first event? One thing I've run into is the widely varying grip at different lots, and changing to a low grip lot makes it much easier to overdrive the car and make it push. I've even been to the same lot two weekends in a row, and some rain before the second event cleaned the track and brought some residues to the surface, and it actually had less grip than the week before.

yeah it was a different lot. so maybe thats it.

[KillboyPowerhead]

Most if not all cars understeer from the factory - it's a safety thing - so if your car is stock it will understeer. A square tire setup is a good start; to add to this consider a larger rear sway bar (I love my JPSS bars ). Solid subframe bushings ought to help here too.

What is your front camber? -1.1° and -1.5°? If so you could try more negative camber, -2.0 to -2.5° (might not be achievable without caster plates but you can get close to -2.0° stock).

[Norm Peterson]

With the front cambers the way they are now, your car should be understeering a little more in right turns than in lefts. Was your second event right turn heavy compared to the first one?

If you don't want to be always swapping between autocross settings and street settings, maybe equalizing the front cambers at a little more negative than -1.5° and standing the rear tires up a little to somewhere in the -0.8° to -0.9° neighborhood would be a reasonable compromise. -0.5° might require a too much more sensitive throttle foot than what you've become accustomed to using.


Norm

[3rdGenAg2010]

Originally Posted by KillboyPowerhead

Most if not all cars understeer from the factory - it's a safety thing - so if your car is stock it will understeer. A square tire setup is a good start; to add to this consider a larger rear sway bar (I love my JPSS bars ). Solid subframe bushings ought to help here too.

What is your front camber? -1.1° and -1.5°? If so you could try more negative camber, -2.0 to -2.5° (might not be achievable without caster plates but you can get close to -2.0° stock).

Yeah I think I'm going to get the 32mm bar. I need to find a Shopi in Houston for alignment. The last shop I couldn't get them to adjust the front camber.

[3rdGenAg2010]

Originally Posted by Norm Peterson

With the front cambers the way they are now, your car should be understeering a little more in right turns than in lefts. Was your second event right turn heavy compared to the first one?

If you don't want to be always swapping between autocross settings and street settings, maybe equalizing the front cambers at a little more negative than -1.5° and standing the rear tires up a little to somewhere in the -0.8° to -0.9° neighborhood would be a reasonable compromise. -0.5° might require a too much more sensitive throttle foot than what you've become accustomed to using.


Norm

Yeah it was right turn heavy. Where as the first race was left turn heavy. Actually now that I think about it on the first course it only felt liked it pushed on the right hand turns.

[The_Stache]

Need thoughts on new setup...

Running autox and hpde's (6-9 events a year) and daily driving on 2nd set of wheels/tires..

Hardware is: coilovers, rear and front sway bars, rear trailing arms and toe arms, 305/30r19s (race setup), 285/35 r20 (daily),poly bushes all around... sitting at about 400 rwhp...

Previs setup worked great... but wondering if I'm leaving more grip on the table..

Front:
Camber: -1.4 to -1.6
Caster : fixed
Toe: 1/16 total

Rear: -1.0 to -1.2
Toe: 0.00 total

Thoughts?

[KillboyPowerhead]

How much do you care about tire wear?

Front camber: -1.5° for tire wear so that you don't have to keep changing camber for the street; -2.0 to -2.5° if you don't care about tire wear.

Front caster: I'd recommend drilling/grinding out the inner radius rod bolt hole (at the subframe) and getting some "caster locks" to increase positive caster, but if not then caster is fixed as you said. Do you have camber (or caster) plates built into the coil-overs?

Front toe: A bit of toe-out will help with turn-in; 0.25° for tire wear, 0.5° for handling (not sure what that is in inches which most people refer to - maybe 1/16" and 1/8"?).

Rear camber: -1.0° for tire wear; -1.5° for handling.

Rear toe: Toe-in helps with keeping the car stable and compensates for dynamic toe changes due to bushing/arm flex; same as front toe but in, so 0.25° to 0.5°.

You may also consider buying a laser thermometer or something to take tire temps so that you can better tune the alignment if you're going to be racing regularly.