Autocross Alignment Specs?
#26
Originally Posted by TeamRX8
what do I know, I'm just a dumb@ss who gets the car aligned regularly, even wastefully so before the Big Event ...
I'm just glad my highly-accurate butt-dyno was able to discern that the car had too much rear toe... never thought it would have almost 1/2" total toe-in at the back... I get what I deserve for listening to clyde.
#27
Originally Posted by John V
Lesson learned, believe me.
I'm just glad my highly-accurate butt-dyno was able to discern that the car had too much rear toe... never thought it would have almost 1/2" total toe-in at the back... I get what I deserve for listening to clyde.
I'm just glad my highly-accurate butt-dyno was able to discern that the car had too much rear toe... never thought it would have almost 1/2" total toe-in at the back... I get what I deserve for listening to clyde.
#29
Originally Posted by TeamRX8
if it's any consolation, I learned the same way ...
#31
Rally Car Racer
I know we've just about talked this topic to death but I'm going to run this by anyway. I'm thinking about this for autocross (all numbers in degrees).
FRONT
CAMBER: -1.75 R/L (no cross camber)
CASTER: Max available after camber set (no cross caster)
TOE: 0.0 R/L
REAR
CAMBER: -1.75 R/L (no cross camber)
TOE: -0.10 IN (-0.20 total toe)
I'm trying to solve my understeer "problem" and at the same time give the rear tires a good hold through the turns while stabilizing the rear with a touch of toe in. Does this sound reasonable?
I want neutral and balanced and an ability to turn quick but not at the cost of sacrificing too much stability. I think this might be a good starting point.
Or should I zero the rear toe? Opinions? Too unstable?
One last thing - I'm using Tein S.Techs so I have a stiffer setup and dropped a little over an inch over the tires and have Koni sports on set to 50 front 80 rear. I think I can get the camber I want because of the drop but we shall see.
Does anyone see anything wrong with this? I'll admit - I barely know what I'm doing (but I'm having fun anyway.)
Thanks.
FRONT
CAMBER: -1.75 R/L (no cross camber)
CASTER: Max available after camber set (no cross caster)
TOE: 0.0 R/L
REAR
CAMBER: -1.75 R/L (no cross camber)
TOE: -0.10 IN (-0.20 total toe)
I'm trying to solve my understeer "problem" and at the same time give the rear tires a good hold through the turns while stabilizing the rear with a touch of toe in. Does this sound reasonable?
I want neutral and balanced and an ability to turn quick but not at the cost of sacrificing too much stability. I think this might be a good starting point.
Or should I zero the rear toe? Opinions? Too unstable?
One last thing - I'm using Tein S.Techs so I have a stiffer setup and dropped a little over an inch over the tires and have Koni sports on set to 50 front 80 rear. I think I can get the camber I want because of the drop but we shall see.
Does anyone see anything wrong with this? I'll admit - I barely know what I'm doing (but I'm having fun anyway.)
Thanks.
#32
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Originally Posted by The Mighty Red
REAR
CAMBER: -1.75 R/L (no cross camber)
TOE: -0.10 IN (-0.20 total toe)
I'm trying to solve my understeer "problem" and at the same time give the rear tires a good hold through the turns while stabilizing the rear with a touch of toe in.
CAMBER: -1.75 R/L (no cross camber)
TOE: -0.10 IN (-0.20 total toe)
I'm trying to solve my understeer "problem" and at the same time give the rear tires a good hold through the turns while stabilizing the rear with a touch of toe in.
#34
Rally Car Racer
I honestly do not know if negative toe is "in" or "out". I'll be sure the tech knows I mean "in" and get the difinitive answer on that.
According to this chart on TireRack:
http://www.tirerack.com/tires/tirete....jsp?techid=58
It shows you should increase rear toe-in to decrease understeer.
If this chart is correct, it looks like it could be pretty useful.
I guess I'll just try this setup it and see what happens. Thanks.
According to this chart on TireRack:
http://www.tirerack.com/tires/tirete....jsp?techid=58
It shows you should increase rear toe-in to decrease understeer.
If this chart is correct, it looks like it could be pretty useful.
I guess I'll just try this setup it and see what happens. Thanks.
Last edited by The Mighty Red; 05-11-2006 at 08:52 AM.
#37
Rally Car Racer
You are right - it was a typo. How frustrating to find the right info! But I'm glad you said something before I took their word for it and screwed something up. Thanks.
I found a pretty decent article that says, "toe-out encourages the initiation of a turn, while toe-in discourages it. The toe setting on a particular car becomes a tradeoff between the straight-line stability afforded by toe-in and the quick steering response promoted by toe-out. Toe settings at the rear have essentially the same effect on wear, directional stability and turn-in as they do on the front. However, it is rare to set up a rear-drive race car toed out in the rear, since doing so causes excessive oversteer, particularly when power is applied"
Since understeer has been my enemy, I definately don't want to toe the rear wheels in. But I think that rear toe out might take it too far the other way. So, maybe I should set toes to ZERO front and back because:
1) when torque is applied to the rear drive wheels, they pull themselves forward and try to create toe-in. So setting these to zero would be a good place to start and a trade off between turn ability and stability under acceleration (in theory) without too much likelihood for oversteer.
2) when then non-driven front wheels are pushed, they tend to toe out. Setting these to zero will probably drastically reduce understeer especially while turning under acceleration (in theory again).
I found a pretty decent article that says, "toe-out encourages the initiation of a turn, while toe-in discourages it. The toe setting on a particular car becomes a tradeoff between the straight-line stability afforded by toe-in and the quick steering response promoted by toe-out. Toe settings at the rear have essentially the same effect on wear, directional stability and turn-in as they do on the front. However, it is rare to set up a rear-drive race car toed out in the rear, since doing so causes excessive oversteer, particularly when power is applied"
Since understeer has been my enemy, I definately don't want to toe the rear wheels in. But I think that rear toe out might take it too far the other way. So, maybe I should set toes to ZERO front and back because:
1) when torque is applied to the rear drive wheels, they pull themselves forward and try to create toe-in. So setting these to zero would be a good place to start and a trade off between turn ability and stability under acceleration (in theory) without too much likelihood for oversteer.
2) when then non-driven front wheels are pushed, they tend to toe out. Setting these to zero will probably drastically reduce understeer especially while turning under acceleration (in theory again).
#38
1935 lbs. FTW!
Thread Starter
Originally Posted by Winning 8
I think you should take some toe out, try setting it to 0.05 each side and see if it's fix the problem.
-1.75 camber
0 toe
max caster
-1.75 camber
0 toe
.05 toe in each side, .10 total (basically almost 0 toe but slightly toe in)
Does that sound right? Also shouldn't the front camber be more than the rear usually?
#40
Sparky!
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Hey Mark,
Care to share some of the tips and tricks for getting -2.5 degrees out of the front of a B Stock car? I'm sure some of it involves the typical suspects (loosen everything and give it a solid yank in the right direction, degassed shocks, etc.), but Jon and I were only able to get roughly -1.2 out of the front of his car. The car still felt pretty good in the tight stuff at the Mineral Wells Pro, but I've yet to meet a Stock car that didn't respond well to a little more front camber. If you don't want to publicize it, you can PM me.
Care to share some of the tips and tricks for getting -2.5 degrees out of the front of a B Stock car? I'm sure some of it involves the typical suspects (loosen everything and give it a solid yank in the right direction, degassed shocks, etc.), but Jon and I were only able to get roughly -1.2 out of the front of his car. The car still felt pretty good in the tight stuff at the Mineral Wells Pro, but I've yet to meet a Stock car that didn't respond well to a little more front camber. If you don't want to publicize it, you can PM me.
Last edited by altiain; 05-28-2006 at 10:34 AM.
#41
Rally Car Racer
Originally Posted by Winning 8
you could go a littlr less rear camber too
may be 1.5 with 0.05 toe on each side.
may be 1.5 with 0.05 toe on each side.
#42
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Originally Posted by TeamRX8
we've seen as high as -2.5 degree front camber on OE springs, it depends on what else you do or know ...
teamrx8, dannobre, i've pm'd you about this topic earlier today. thanks!
#43
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I could only get -.9 out of mine in the front. Maybe if we give to the Mark STU fund to aid in his transmission rehabilitation program we can get this valuable information.
#44
Rally Car Racer
I got aligned yesterday. Got -2.0 camber on both fronts easy. This is the same front camber that Mark is using. I believe (but can't say for 100% sure) it has something to do with being lowered.
Mark's front fender is lowered down to (pretty close to) the same height as what I ended up with when I installed my S.Tech springs. (I think)
Mark's front fender is lowered down to (pretty close to) the same height as what I ended up with when I installed my S.Tech springs. (I think)
#48
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Originally Posted by dannobre
The car will only get that kind of camber if it is lower than stock..........I got -2.6deg front...but I'm dropped to a bit below 26" ride height. I could get -1.6 deg out of the car stock with the caster adjusted for max camber
#50
No respecter of malarkey
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The car mentioned is SCCA Stock Class legal, which means it has the OE springs and OE spring perch height ....
my STU racer is lowered, but I am only running 2.0 deg camber in the front, the 500# front springs limit body roll particularly since we're only allowed to run a minimum 140 treadwear-rating street tire
my STU racer is lowered, but I am only running 2.0 deg camber in the front, the 500# front springs limit body roll particularly since we're only allowed to run a minimum 140 treadwear-rating street tire
Last edited by TeamRX8; 06-08-2006 at 07:34 PM.