oh brother..another request for alignment specs..
03-08-2012, 11:57 AM
#1
Drifting
Thread Starter
oh brother..another request for alignment specs..
apologies for yet another request for suggested alignment specs but haven't found anything for my specific set-up so...........
anyone willing to suggest some good alignment specs for a square set-up on a dedicated C5Z track / DE / TT car:
- C5Z rear wheels - all around
- 315 Hoosier A's - all around
- T1 bars
- G2 coil-overs
- poly a-arm bushes
- pfadt camber kit (w/ pfadt FU a-arm pins - so basically unlimited negative camber opportunities).
Lots of guys with this basic set-up so..whats been working for you ?
anyone willing to suggest some good alignment specs for a square set-up on a dedicated C5Z track / DE / TT car:
- C5Z rear wheels - all around
- 315 Hoosier A's - all around
- T1 bars
- G2 coil-overs
- poly a-arm bushes
- pfadt camber kit (w/ pfadt FU a-arm pins - so basically unlimited negative camber opportunities).
Lots of guys with this basic set-up so..whats been working for you ?
03-08-2012, 01:38 PM
#3
Drifting
Member Since: Dec 2005
Location: Dayton, OH
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Those numbers you have don't really apply to a dedicated track car or race car. (unless I didn't read down far enough)
That is what I ran when I still drove my car on the street
03-08-2012, 01:41 PM
#4
Safety Car
apologies for yet another request for suggested alignment specs but haven't found anything for my specific set-up so...........
anyone willing to suggest some good alignment specs for a square set-up on a dedicated C5Z track / DE / TT car:
- C5Z rear wheels - all around
- 315 Hoosier A's - all around
- T1 bars
- G2 coil-overs
- poly a-arm bushes
- pfadt camber kit (w/ pfadt FU a-arm pins - so basically unlimited negative camber opportunities).
Lots of guys with this basic set-up so..whats been working for you ?
anyone willing to suggest some good alignment specs for a square set-up on a dedicated C5Z track / DE / TT car:
- C5Z rear wheels - all around
- 315 Hoosier A's - all around
- T1 bars
- G2 coil-overs
- poly a-arm bushes
- pfadt camber kit (w/ pfadt FU a-arm pins - so basically unlimited negative camber opportunities).
Lots of guys with this basic set-up so..whats been working for you ?
Front
As much negative camber as you can get. Meaning camber blocks to move the LCA as out as far as it'll go and Pfadt's UCA mounts oriented in the "more camber" position. This will usually get you -2.7+. I'm at -2.85 on both sides up front.
Since I'm using the camber blocks my caster is fixed... I don't even pay attention to it, but generally you want it over +6.
I run 1/16" toe out per side so 1/8 sum toe.
Rear
As much negative camber as you can get. Using camber blocks I'm about -1.2 LR and -1.65 RR. Also remember having you sitting in the car changes things a bunch. I'm fine leaving mine as is, but the real way to fix it is to loosen the rear cradle and pry it over to the driver's side to try and equalize both sides at -1.4. The variance is from frame tolerances and rear cradle tolerances when the LCA is moved as far as it'll go.
I run 1/16" toe in per side out back so 1/8 sum toe.
Last edited by travisnd; 03-08-2012 at 02:28 PM.
03-08-2012, 02:06 PM
#5
Instructor
^ agreed the more camber you can get the better the Hoosier's will work. the most I could get outta mine was 2.2 up front(i need blocks).
I had trouble on the rear also max at 1.2, pryed the rear cradle over now got 1.7 much better on the tires. I was wearing the rear outside badly.
I had trouble on the rear also max at 1.2, pryed the rear cradle over now got 1.7 much better on the tires. I was wearing the rear outside badly.
03-08-2012, 03:43 PM
#6
Drifting
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Location: Dayton, OH
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Corvette suspension has camber gain built into the front and rear control arms.
The real problem is that people run too stiff of a spring and/or roll-bar with wimpy rubber/poly bushings and when they go into a corner etc. they give up the camber gain because the control arms move in unpredictable ways. Basically they end up with positive camber instead of increased negative camber as designed.
Generally, when you compress the suspension on a C5/6 due to the shorter UCA you gain negative camber the more the suspension compresses.
With the amount of gain built in it would be very difficult to scrub the outside edge of the tire. Therefore one of a few things might be going on in this situation.
1) Bushings moving/compressing and giving up all the static camber and built in camber gain or
2) very low tire pressures/soft sidewalls
Poly bushings help but the compression loads that can be created by a 3000+lbs car going into a corner in excess of 1 G and then add the leverage available from the wheel/tire to the pivot point at the end of the control arm and even poly will compress a significant amount.
Using spherical /bearing pivot points is the only way to fix this issue.
Yes you can run ridiculous amounts of static camber to save the edges of your tires but you will give up substantial grip and handling under many different conditions by doing this.
The point is, Hoosiers don't NEED ridiculous amounts of negative camber to "work", they just need to be left in contact with the pavement.
If you aren't going to fix the actual problem then a better statement would be
"Tires on C5 or C6 Corvettes need ridiculous amounts of static camber to not wear the outer edges if you use the car on the track with flexible pivot points on the control arms."
03-08-2012, 04:10 PM
#8
Instructor
Not to go against convention and start a $%!# storm but this isn't really true.
Corvette suspension has camber gain built into the front and rear control arms.
The real problem is that people run too stiff of a spring and/or roll-bar with wimpy rubber/poly bushings and when they go into a corner etc. they give up the camber gain because the control arms move in unpredictable ways. Basically they end up with positive camber instead of increased negative camber as designed.
Generally, when you compress the suspension on a C5/6 due to the shorter UCA you gain negative camber the more the suspension compresses.
With the amount of gain built in it would be very difficult to scrub the outside edge of the tire. Therefore one of a few things might be going on in this situation.
1) Bushings moving/compressing and giving up all the static camber and built in camber gain or
2) very low tire pressures/soft sidewalls
Poly bushings help but the compression loads that can be created by a 3000+lbs car going into a corner in excess of 1 G and then add the leverage available from the wheel/tire to the pivot point at the end of the control arm and even poly will compress a significant amount.
Using spherical /bearing pivot points is the only way to fix this issue.
Yes you can run ridiculous amounts of static camber to save the edges of your tires but you will give up substantial grip and handling under many different conditions by doing this.
The point is, Hoosiers don't NEED ridiculous amounts of negative camber to "work", they just need to be left in contact with the pavement.
If you aren't going to fix the actual problem then a better statement would be
"Tires on C5 or C6 Corvettes need ridiculous amounts of static camber to not wear the outer edges if you use the car on the track with flexible pivot points on the control arms."
Corvette suspension has camber gain built into the front and rear control arms.
The real problem is that people run too stiff of a spring and/or roll-bar with wimpy rubber/poly bushings and when they go into a corner etc. they give up the camber gain because the control arms move in unpredictable ways. Basically they end up with positive camber instead of increased negative camber as designed.
Generally, when you compress the suspension on a C5/6 due to the shorter UCA you gain negative camber the more the suspension compresses.
With the amount of gain built in it would be very difficult to scrub the outside edge of the tire. Therefore one of a few things might be going on in this situation.
1) Bushings moving/compressing and giving up all the static camber and built in camber gain or
2) very low tire pressures/soft sidewalls
Poly bushings help but the compression loads that can be created by a 3000+lbs car going into a corner in excess of 1 G and then add the leverage available from the wheel/tire to the pivot point at the end of the control arm and even poly will compress a significant amount.
Using spherical /bearing pivot points is the only way to fix this issue.
Yes you can run ridiculous amounts of static camber to save the edges of your tires but you will give up substantial grip and handling under many different conditions by doing this.
The point is, Hoosiers don't NEED ridiculous amounts of negative camber to "work", they just need to be left in contact with the pavement.
If you aren't going to fix the actual problem then a better statement would be
"Tires on C5 or C6 Corvettes need ridiculous amounts of static camber to not wear the outer edges if you use the car on the track with flexible pivot points on the control arms."
Thanks in advance,
Greg
03-08-2012, 05:56 PM
#9
Melting Slicks
I was guilty of this. Just going with what others told me I should run in a particular tire. We were tearing through left fronts like they were made of tissue paper. I was given the suggestion and tried adding air. 4 pounds made a significant difference in lessening shoulder wear and also better 1st and 2nd lap grip levels.
03-08-2012, 10:04 PM
#10
No one should give anyone else their suspension setup unless their cars are exactly alike or without a disclaimer for when the guy lunches the car
The only way to get them is with a pyrometer at the track. Tire temps tell all. There are rules of thumbs for track and race cars though.
stock suspensions suck- well not really but you get the idea.
you eventually will be running negative camber at least on the front
you will be running some toe out or in at some point
if you don't torque your wheel nuts you are an idiot (just thought I'd throw that one in).
so add a bit everywhere and go from there with the pyro. You will be very happy when your contact patch is optimized with any suspension. Then start changing things and start all over (sigh) its always a work in progress
The only way to get them is with a pyrometer at the track. Tire temps tell all. There are rules of thumbs for track and race cars though.
stock suspensions suck- well not really but you get the idea.
you eventually will be running negative camber at least on the front
you will be running some toe out or in at some point
if you don't torque your wheel nuts you are an idiot (just thought I'd throw that one in).
so add a bit everywhere and go from there with the pyro. You will be very happy when your contact patch is optimized with any suspension. Then start changing things and start all over (sigh) its always a work in progress
