Alignment Specs (a compromise)
04-06-2014, 02:39 PM
#1
Racer
Thread Starter
Alignment Specs (a compromise)
I have a 2000 C5 Z51 with stock alignment.
I'd like to get an alignment that is a compromise for autocross, drag racing and the street.
This is the alignment I'm thinking of going with. Please let me know if you think this makes sense or have any suggestions.
Front-----------
Camber -1.2° (Pfadt Performance Street - Street Tires)
Caster +8.5° (~max)
Toe-Out 0.10° (stock 00 Z51)
Rear------------
Camber -0.68° (stock Z06)
Toe-In 0.17° (Pfadt Performance Street min)
Thrust 0°
Current Suspension Set-up:
C6 Grand Sport shocks all around
T1 front sway bar
C6 Grand Sport rear sway bar
C5 Z51 springs all around
Street Wheels & Tires:
275/40R17 front on 9.5" wheels
295/35R18 rear on 10.5" wheels
I run 200 wear tires on the street and R-Compound for autocross
http://www.pfadtracing.com/docs/camb...t-settings.pdf
http://www.pfadtracing.com/blog/wp-c...-9.12.2011.pdf
I'd like to get an alignment that is a compromise for autocross, drag racing and the street.
This is the alignment I'm thinking of going with. Please let me know if you think this makes sense or have any suggestions.
Front-----------
Camber -1.2° (Pfadt Performance Street - Street Tires)
Caster +8.5° (~max)
Toe-Out 0.10° (stock 00 Z51)
Rear------------
Camber -0.68° (stock Z06)
Toe-In 0.17° (Pfadt Performance Street min)
Thrust 0°
Current Suspension Set-up:
C6 Grand Sport shocks all around
T1 front sway bar
C6 Grand Sport rear sway bar
C5 Z51 springs all around
Street Wheels & Tires:
275/40R17 front on 9.5" wheels
295/35R18 rear on 10.5" wheels
I run 200 wear tires on the street and R-Compound for autocross
http://www.pfadtracing.com/docs/camb...t-settings.pdf
http://www.pfadtracing.com/blog/wp-c...-9.12.2011.pdf
Last edited by tb30570; 04-08-2014 at 06:53 PM.
04-06-2014, 03:20 PM
#2
Race Director
jUST A COUPLE OF ITEMS, NOT A FULL ANALYSIS:
IMO some more rear neg camber is not going to hurt straight line accel.
Keep in mind toe in or out wears out tires at a pretty quick rate.
Good Luck.
IMO some more rear neg camber is not going to hurt straight line accel.
Keep in mind toe in or out wears out tires at a pretty quick rate.
Good Luck.
04-06-2014, 03:32 PM
#3
Melting Slicks
If you compromise on something like this you get something that isn't very good at anything.
In autocross you will end up beating up the outside of your tires, and on the strip you will start to lose traction.
Usually I would recommend about a difference of half a degree between front and rear to keep it balanced. For that you really want a half a degree more negative in the front, or a half a degree less negative in the back..
Also the rear toe is a bit bigger than I would like to see.
In autocross you will end up beating up the outside of your tires, and on the strip you will start to lose traction.
Usually I would recommend about a difference of half a degree between front and rear to keep it balanced. For that you really want a half a degree more negative in the front, or a half a degree less negative in the back..
Also the rear toe is a bit bigger than I would like to see.
04-06-2014, 11:26 PM
#4
Safety Car
I just discovered toe out today at the track in my Camaro, there is absolutely NO going back. Makes me want to try it in the Z now but it doesn't see the track anymore. It was not what I thought it would be, the car simply turns now.
04-07-2014, 03:28 PM
#6
Drifting
on a road course or autocross? that sounds dangerous to me in a vette ... maybe camaro is inherently more difficult to get to rotate?
04-07-2014, 06:17 PM
#7
Racer
Thread Starter
04-07-2014, 06:47 PM
#8
Former Vendor
Member Since: Aug 2005
Location: Lewisville TX
Posts: 16,898
Received 406 Likes
on
300 Posts
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
Always toe out in the front and always toe in at the rear of a car for almost any AutoX or road racing event.
In some cases you might have to run toe in on the front of the car for drag racing so the car would be close to zero toe at speed...but that takes a bit more calculations on bump steer, and position of the suspension at speed.
I do completely agree with if you try to run a 'average' you'll have something that isn't really that good at anything other than possibly destroying tires.
Couple of quotes I have heard over the years and I will stick by when it comes to setup.
"Doesn't matter if you have the best parts in the world, if the tires are not pointed the right way it doesn't matter"
"Don't give your car what someone else has, give it what it asks for"
Now on the second one....Corvette's will have a good 'general' setting that works pretty well, and you can dial the rest of that in based on tire wear, tire temp, and how the car behaves on track.
That being said...I would look at something similar to this
Front-----------
Camber -1.5°
Caster +7.5°
Toe-OUT 0.10° (total 1/16" out approx)
Rear------------
Camber -1.25°
Toe-In 0.17° (total 1/8" in approx)
Thrust 0°
The race cars....generally run something similar to the following (DOT tire / Slick)
Front-----------
Camber -2.0° / -2.2° to -2.8°
Caster +6.5° / +6.0° to +6.8°
Toe- 1/8" total toe OUT
Rear------------
Camber -1.5° / -1.8 to -2.1°
Toe- 3/16 to 1/4" total toe IN
Thrust 0°
In some cases you might have to run toe in on the front of the car for drag racing so the car would be close to zero toe at speed...but that takes a bit more calculations on bump steer, and position of the suspension at speed.
I do completely agree with if you try to run a 'average' you'll have something that isn't really that good at anything other than possibly destroying tires.
Couple of quotes I have heard over the years and I will stick by when it comes to setup.
"Doesn't matter if you have the best parts in the world, if the tires are not pointed the right way it doesn't matter"
"Don't give your car what someone else has, give it what it asks for"
Now on the second one....Corvette's will have a good 'general' setting that works pretty well, and you can dial the rest of that in based on tire wear, tire temp, and how the car behaves on track.
That being said...I would look at something similar to this
Front-----------
Camber -1.5°
Caster +7.5°
Toe-OUT 0.10° (total 1/16" out approx)
Rear------------
Camber -1.25°
Toe-In 0.17° (total 1/8" in approx)
Thrust 0°
The race cars....generally run something similar to the following (DOT tire / Slick)
Front-----------
Camber -2.0° / -2.2° to -2.8°
Caster +6.5° / +6.0° to +6.8°
Toe- 1/8" total toe OUT
Rear------------
Camber -1.5° / -1.8 to -2.1°
Toe- 3/16 to 1/4" total toe IN
Thrust 0°
Last edited by Anthony @ LGMotorsports; 04-07-2014 at 06:52 PM.
04-08-2014, 06:37 PM
#9
Racer
Thread Starter
04-08-2014, 06:41 PM
#10
Racer
Thread Starter
09-01-2012, 01:16 am
very common to have more front than rear, especially for auto-x. I run -2.5 front and -1.3 rear. Need more in the front for good turn-in, less in the rear to get power down out of slow corners. (many people don't go over -1 in rear, with all they can get in front.) i think the road-racers try to get more in the rear for slightly better grip in long sweepers typical of road courses. (not typical of auto-x courses.) balance of the car (oversteer vs understeer) is mostly sensitive to rake and toe.
I had to move my front subframe to get -2.5 on each side. Limited to -2.1 before doing that.
I had to move my front subframe to get -2.5 on each side. Limited to -2.1 before doing that.
04-08-2014, 06:45 PM
#11
Racer
Thread Starter
09-02-2012, 07:43 pm
from my perspective, i would go with what avizandum suggested. It's a good starting point for a street driven/autocross car. My semi-dedicated autocross cars have a lot more negative camber up front and a touch more negative in the rear than his suggestions. But i'm willing to live with increased tire wear for better autocross performance, and i haven't hit the drag strip with my cars in a few years.
Caster - i like to go with as much positive caster as i can. It has the effect of adding negative camber at high steering angles. Autocrossing has a lot of high steering angle inputs, as compared to track session.
Front toe - you can always change toe really easily. I'd align it at zero toe and then you can always adjust one flat at a time to suit your preference.
Front camber - i personally like as much as i can get (within reason, like -2 to -2.5). Autocrossing has, as stated before, a lot of low speed, high angle corners. You need front negative camber to have the front end bite.
Have fun!
Caster - i like to go with as much positive caster as i can. It has the effect of adding negative camber at high steering angles. Autocrossing has a lot of high steering angle inputs, as compared to track session.
Front toe - you can always change toe really easily. I'd align it at zero toe and then you can always adjust one flat at a time to suit your preference.
Front camber - i personally like as much as i can get (within reason, like -2 to -2.5). Autocrossing has, as stated before, a lot of low speed, high angle corners. You need front negative camber to have the front end bite.
Have fun!
04-08-2014, 06:47 PM
#12
Racer
Thread Starter
09-03-2012, 11:16 am
i've noticed that if you don't have the grip of a good tire, you can hurt yourself with too much negative camber. Use a pyrometer and if you are running hot only on the inside edge of the tire after a run, you may have too much neg. I think a good starting point is perhaps 2 deg neg in front. Multiply that by .75 and you have 1.5 neg in the rear. As for toe, i like a little out in front. I may toe it in a hair at the rear. All this is with my 180 lbs sitting in the car and a full tank.
I'm setting up my frc this week. I'm gonna do some track trials and auto-x.
I'm setting up my frc this week. I'm gonna do some track trials and auto-x.
04-08-2014, 06:57 PM
#13
Racer
Thread Starter
Thank you all for your advice. I'd difficult to make a decision because I've received a few different perspectives. I've updated my plan (see top post) based on all your feedback. Please take a look and let me know if this is pretty close to a good idea or just a terrible idea.
04-12-2014, 01:35 AM
#14
Safety Car
Not covering up corner entry understeer with excessive trailbraking makes it easier to be consistent because you're dealing with less oversteer, and the degree of oversteer seems to depend largely on the temperature of the tires. It's easy to maintain consistency with corner exit oversteer, but when you induce it from the get go you open yourself up to losing mid corner speed if you don't execute it flawlessly. Even then, it's still not as fast as just hooking through a corner. I'll probably look at dialing out some rear bias now so I can trail in effectively while maintaining traction on those late apex hairpins.
Last edited by Supercharged111; 04-12-2014 at 01:39 AM.
