corner balanced the GS today - what a great car!
09-19-2010, 08:16 PM
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corner balanced the GS today - what a great car!
Lowered the car down as much as I could on the stock adjusters, which as I noted from another's thread, the rear is the limiter... I could only get turn full turns further down in the rear tho' I have plenty in front.
Nonetheless, lowered the rear max, leveled it out and then did the front by eye for a pleasing look. Put it on the scales and it was all setup for circle track racing
Plenty of cross in it, almost 53%. A few turns opposite cross and came in right at 50.5% which was close 'nuf for me. I had just under 3/4 tank of fuel in the car as I usually fill up for the track and run a day and leave with about 1/2 tank, so just crossed it in the middle.
Next time I have the wheels off I will just crank a couple more turns into the opposite cross and know it is either neutral or to get below 50% since the road course is mostly rights and all the high speed turns are rights.
To be able to adjust the corner weights on a factory vehicles is just awesome in this price range. Super cars with adj coilovers yeah, but a $60K Vette... pretty damn cool
And easy too.
Crazy part is when it is all said and done, if I get out of the car the cross only goes up 0.1%. That is a seriously balanced car for a factory production vehicle. Sure they aren't balanced 50/50 from the factory, that makes sense given the time it would take to do that, but the great point is they can be by the owner and the owner will find it is a very balanced car with or without driver.
3351 lbs without me at that fuel level... the GS is a bit heavier than the others, but they have to ballast up to 3500 lbs in GT1 to slow down for the other guys anyway
Nonetheless, lowered the rear max, leveled it out and then did the front by eye for a pleasing look. Put it on the scales and it was all setup for circle track racing
Plenty of cross in it, almost 53%. A few turns opposite cross and came in right at 50.5% which was close 'nuf for me. I had just under 3/4 tank of fuel in the car as I usually fill up for the track and run a day and leave with about 1/2 tank, so just crossed it in the middle.Next time I have the wheels off I will just crank a couple more turns into the opposite cross and know it is either neutral or to get below 50% since the road course is mostly rights and all the high speed turns are rights.
To be able to adjust the corner weights on a factory vehicles is just awesome in this price range. Super cars with adj coilovers yeah, but a $60K Vette... pretty damn cool
And easy too.Crazy part is when it is all said and done, if I get out of the car the cross only goes up 0.1%. That is a seriously balanced car for a factory production vehicle. Sure they aren't balanced 50/50 from the factory, that makes sense given the time it would take to do that, but the great point is they can be by the owner and the owner will find it is a very balanced car with or without driver.
3351 lbs without me at that fuel level... the GS is a bit heavier than the others, but they have to ballast up to 3500 lbs in GT1 to slow down for the other guys anyway
09-19-2010, 09:15 PM
#2
Lowered the car down as much as I could on the stock adjusters, which as I noted from another's thread, the rear is the limiter... I could only get turn full turns further down in the rear tho' I have plenty in front.
Nonetheless, lowered the rear max, leveled it out and then did the front by eye for a pleasing look. Put it on the scales and it was all setup for circle track racing Plenty of cross in it, almost 53%. A few turns opposite cross and came in right at 50.5% which was close 'nuf for me. I had just under 3/4 tank of fuel in the car as I usually fill up for the track and run a day and leave with about 1/2 tank, so just crossed it in the middle.
Next time I have the wheels off I will just crank a couple more turns into the opposite cross and know it is either neutral or to get below 50% since the road course is mostly rights and all the high speed turns are rights.
To be able to adjust the corner weights on a factory vehicles is just awesome in this price range. Super cars with adj coilovers yeah, but a $60K Vette... pretty damn cool And easy too.
Crazy part is when it is all said and done, if I get out of the car the cross only goes up 0.1%. That is a seriously balanced car for a factory production vehicle. Sure they aren't balanced 50/50 from the factory, that makes sense given the time it would take to do that, but the great point is they can be by the owner and the owner will find it is a very balanced car with or without driver.
3351 lbs without me at that fuel level... the GS is a bit heavier than the others, but they have to ballast up to 3500 lbs in GT1 to slow down for the other guys anyway
Nonetheless, lowered the rear max, leveled it out and then did the front by eye for a pleasing look. Put it on the scales and it was all setup for circle track racing
Plenty of cross in it, almost 53%. A few turns opposite cross and came in right at 50.5% which was close 'nuf for me. I had just under 3/4 tank of fuel in the car as I usually fill up for the track and run a day and leave with about 1/2 tank, so just crossed it in the middle.Next time I have the wheels off I will just crank a couple more turns into the opposite cross and know it is either neutral or to get below 50% since the road course is mostly rights and all the high speed turns are rights.
To be able to adjust the corner weights on a factory vehicles is just awesome in this price range. Super cars with adj coilovers yeah, but a $60K Vette... pretty damn cool
And easy too.Crazy part is when it is all said and done, if I get out of the car the cross only goes up 0.1%. That is a seriously balanced car for a factory production vehicle. Sure they aren't balanced 50/50 from the factory, that makes sense given the time it would take to do that, but the great point is they can be by the owner and the owner will find it is a very balanced car with or without driver.
3351 lbs without me at that fuel level... the GS is a bit heavier than the others, but they have to ballast up to 3500 lbs in GT1 to slow down for the other guys anyway
Does it drive any different? Is it a rougher ride on the street?
09-19-2010, 09:20 PM
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it won't change the ride at all, it just redistributes the weight of the car... the weight is the weight. It won't do much for street driving, but it will make it more consistent to drive on a race track. The car will want to corner left the same as right. If you bias one way, it is just that, the car will turn better one way than the other. It isn't noticeable in the wheel typically (you won't necessarily feel it) but it will show up on the times when you get the cross right for the track configuration.
NASCAR for instance is all lefts, so you bias the car to turn left. At some point you can have too much cross weight and the car will not be as fast, but a typical setup for road racing is 50/50.
NASCAR for instance is all lefts, so you bias the car to turn left. At some point you can have too much cross weight and the car will not be as fast, but a typical setup for road racing is 50/50.
Last edited by CyberGS; 09-22-2010 at 04:00 PM.
09-20-2010, 09:24 PM
#4
Racer
nice. BTW, we had 50.7% cross at the track friday (asphalt circle track)
The cross usually stays pretty consistent when the driver gets in& out & with fuel load for that matter in the late model.
In the vette i'm guessing the cross will go down when that fuel comes out of that LH tank on the last 9 gal
The cross usually stays pretty consistent when the driver gets in& out & with fuel load for that matter in the late model.
In the vette i'm guessing the cross will go down when that fuel comes out of that LH tank on the last 9 gal
09-20-2010, 09:32 PM
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Did the same thing a while back... Don't forget to put some anti-seize on jacking screws so it's just as easy next time . I didn't and did it suck when it got rusty, broke 2 10mm wrenches.
It does make a difference.
Mike
. I didn't and did it suck when it got rusty, broke 2 10mm wrenches.It does make a difference.
Mike
09-21-2010, 01:23 AM
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A0-08 - yeah, I am still set to make lefts a bit 
I am going to put more load in opposite cross (get the cross below 50%) since the road course I run is mostly rights and fast rights. Also I tend to run on the high side of the fuel capacity since I have to get home afterward, which means I run from full down to around 1/2 tank, which IIRC on these cars, would be all right tank loss, meaning I would have the cross increase. Make sense and agrees with you if I were to lower the left tank, I would lose cross, I just won't get that low on fuel.
Skunkworks - good point, wouldn't have thought to back those out and get some anti-seize in there. It makes sense but I wouldn't have expect them to rust up that bad! Geez.
trauma - as oldmansan says, it is really better to have someone do it that knows how to... years ago when I didn't have scales, I would go to a performance alignment shop and they would charge me $120 extra at the time to do the corner weights with an alignment. If you can find an alignment shop to do that for you, just do that and have it set right at 50%. Since you wouldn't have any reason to mess with that ever again (you won't be tuning for the track at a given event) you can just do it the one time.
I mess with cross weights a lot of my race car trying to see if I can get some gains in time biasing for more rights than lefts for instance, so I am always messing with the scales. I mess with spring rates as well, etc etc that will always keep that moving around, so I needed to buy scales. Don't bother, just pay a shop one time
I am going to put more load in opposite cross (get the cross below 50%) since the road course I run is mostly rights and fast rights. Also I tend to run on the high side of the fuel capacity since I have to get home afterward, which means I run from full down to around 1/2 tank, which IIRC on these cars, would be all right tank loss, meaning I would have the cross increase. Make sense and agrees with you if I were to lower the left tank, I would lose cross, I just won't get that low on fuel.Skunkworks - good point, wouldn't have thought to back those out and get some anti-seize in there. It makes sense but I wouldn't have expect them to rust up that bad! Geez.
trauma - as oldmansan says, it is really better to have someone do it that knows how to... years ago when I didn't have scales, I would go to a performance alignment shop and they would charge me $120 extra at the time to do the corner weights with an alignment. If you can find an alignment shop to do that for you, just do that and have it set right at 50%. Since you wouldn't have any reason to mess with that ever again (you won't be tuning for the track at a given event) you can just do it the one time.
I mess with cross weights a lot of my race car trying to see if I can get some gains in time biasing for more rights than lefts for instance, so I am always messing with the scales. I mess with spring rates as well, etc etc that will always keep that moving around, so I needed to buy scales. Don't bother, just pay a shop one time
09-21-2010, 01:33 AM
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St. Jude Donor '09
A0-08 - yeah, I am still set to make lefts a bit I am going to put more load in opposite cross (get the cross below 50%) since the road course I run is mostly rights and fast rights. Also I tend to run on the high side of the fuel capacity since I have to get home afterward, which means I run from full down to around 1/2 tank, which IIRC on these cars, would be all right tank loss, meaning I would have the cross increase. Make sense and agrees with you if I were to lower the left tank, I would lose cross, I just won't get that low on fuel.
Skunkworks - good point, wouldn't have thought to back those out and get some anti-seize in there. It makes sense but I wouldn't have expect them to rust up that bad! Geez.
trauma - as oldmansan says, it is really better to have someone do it that knows how to... years ago when I didn't have scales, I would go to a performance alignment shop and they would charge me $120 extra at the time to do the corner weights with an alignment. If you can find an alignment shop to do that for you, just do that and have it set right at 50%. Since you wouldn't have any reason to mess with that ever again (you won't be tuning for the track at a given event) you can just do it the one time.
I mess with cross weights a lot of my race car trying to see if I can get some gains in time biasing for more rights than lefts for instance, so I am always messing with the scales. I mess with spring rates as well, etc etc that will always keep that moving around, so I needed to buy scales. Don't bother, just pay a shop one time
I am going to put more load in opposite cross (get the cross below 50%) since the road course I run is mostly rights and fast rights. Also I tend to run on the high side of the fuel capacity since I have to get home afterward, which means I run from full down to around 1/2 tank, which IIRC on these cars, would be all right tank loss, meaning I would have the cross increase. Make sense and agrees with you if I were to lower the left tank, I would lose cross, I just won't get that low on fuel.Skunkworks - good point, wouldn't have thought to back those out and get some anti-seize in there. It makes sense but I wouldn't have expect them to rust up that bad! Geez.
trauma - as oldmansan says, it is really better to have someone do it that knows how to... years ago when I didn't have scales, I would go to a performance alignment shop and they would charge me $120 extra at the time to do the corner weights with an alignment. If you can find an alignment shop to do that for you, just do that and have it set right at 50%. Since you wouldn't have any reason to mess with that ever again (you won't be tuning for the track at a given event) you can just do it the one time.
I mess with cross weights a lot of my race car trying to see if I can get some gains in time biasing for more rights than lefts for instance, so I am always messing with the scales. I mess with spring rates as well, etc etc that will always keep that moving around, so I needed to buy scales. Don't bother, just pay a shop one time
CyberGS, just curious, how much are the scales?
San
09-21-2010, 02:42 AM
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scale prices vary, but here is a brand that isn't the cheapest but is a long standing and popular one with circle track teams. Pretty sturdy and every circle track team I used to work with used this brand, they were not always treated well and stood up to everything I saw thrown at them.
This is a basic, starter set at $1K. So as you can see, if you can have the work done for a couple hundred bucks, you would need to scale the car 5 times to break even, and you didn't have to turn a single wrench, which is why for many guys just having it done is the best option.
http://www.longacreracing.com/catalo...d=1261&catid=1
This is a basic, starter set at $1K. So as you can see, if you can have the work done for a couple hundred bucks, you would need to scale the car 5 times to break even, and you didn't have to turn a single wrench, which is why for many guys just having it done is the best option.
http://www.longacreracing.com/catalo...d=1261&catid=1
09-21-2010, 06:59 AM
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Just curious.
What is the general procedure to adjust static weight & corner weight distribution.
What did you use to adjust the static weight?
How far off is the stock Grand Sport with average driver? FR and LR
Does in interact with the rest of the alignment or ride height?
What is the general procedure to adjust static weight & corner weight distribution.
What did you use to adjust the static weight?
How far off is the stock Grand Sport with average driver? FR and LR
Does in interact with the rest of the alignment or ride height?
Last edited by Dan Wendling; 09-21-2010 at 07:09 AM.
09-21-2010, 01:49 PM
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xxx
Rearranged the order of the questions in order of what you do
What did you use to adjust the static weight? You want to set the car to the ride height and level it out first, that is most important. First, set the tire pressures where you want them WHEN HOT. I found the tires liked being around 35 psi hot on the one track day I did, so for now I assume that and set the pressure there for the scaling, not what the door tag said.
So for the Vette, I lowered the rear down to the lowest setting on the adjusters, both sides. Then I set the front height to match what I wanted for rake by eye, then leveled out the car by using a tape measure from four frame points, symmetric about the center (you can use jacking points for example, you want a big pattern to get best measurements since a tape measure isn't accurate but close 'nuf).
Now it is all level, correct tire pressure, get the scales
What is the general procedure to adjust static weight & corner weight distribution. Basically you level out the scales to each other, then it is best to have a ramp setup so you can drive onto them, or you can jack the car up and put the scales under the tires, but you have to bounce the front and rear, bounce up and down on each sides door sills, bounce front and rear again, then rock the car one last time by hand to try to get the suspension settled back down.
Then you take the total weight of the car and divide it by whatever you like:
1. you can add up the two rear wheels and get rear weight percentage. I was 49.6% rear, meaning 100-49.6 = 50.4% front. VERY BALANCED for a front engine car of course.
2. Take the right front and the left rear, add them together and get the cross weight. "Cross" has been defined by NASCAR guys as anything above 50% on that diagonal, so if you here a guy say he had 51% cross weight, he had 51% of the weight on those two tires. Makes the car want to turn left. If you want to go right, you would go with opposite cross and have a "cross weight percentage" more like 49%... something under 50%. Since road racers go left and right, the starting setting is just 50%.
How far off is the stock Grand Sport with average driver? FR and LR
the cross weight could be anywhere to be honest - the factory is going to generally set the car up with the same height adjusted into the spring bolt front and rear, meaning I had two full turns left on the rear bolts and almost 3/8" of adjustment left on the front from the dealer (they may have lowered it some, who knows). So, with tolerance stackups and so forth, it could be absolutely anywhere. I didn't check stock cross as I didn't care, I knew I was fixing whatever but will say it was very unlikely to be right at 50%.
Key is you have to take the time to level the car (which frankly I was really level with equal adjustments at the springs so left them even) and do the scaling
Does in interact with the rest of the alignment or ride height? As stated, ride height you set where you want it. Adjusting weight for cross should NOT affect ride height.
What did you use to adjust the static weight? You want to set the car to the ride height and level it out first, that is most important. First, set the tire pressures where you want them WHEN HOT. I found the tires liked being around 35 psi hot on the one track day I did, so for now I assume that and set the pressure there for the scaling, not what the door tag said.
So for the Vette, I lowered the rear down to the lowest setting on the adjusters, both sides. Then I set the front height to match what I wanted for rake by eye, then leveled out the car by using a tape measure from four frame points, symmetric about the center (you can use jacking points for example, you want a big pattern to get best measurements since a tape measure isn't accurate but close 'nuf).
Now it is all level, correct tire pressure, get the scales
What is the general procedure to adjust static weight & corner weight distribution. Basically you level out the scales to each other, then it is best to have a ramp setup so you can drive onto them, or you can jack the car up and put the scales under the tires, but you have to bounce the front and rear, bounce up and down on each sides door sills, bounce front and rear again, then rock the car one last time by hand to try to get the suspension settled back down.
Then you take the total weight of the car and divide it by whatever you like:
1. you can add up the two rear wheels and get rear weight percentage. I was 49.6% rear, meaning 100-49.6 = 50.4% front. VERY BALANCED for a front engine car of course.
2. Take the right front and the left rear, add them together and get the cross weight. "Cross" has been defined by NASCAR guys as anything above 50% on that diagonal, so if you here a guy say he had 51% cross weight, he had 51% of the weight on those two tires. Makes the car want to turn left. If you want to go right, you would go with opposite cross and have a "cross weight percentage" more like 49%... something under 50%. Since road racers go left and right, the starting setting is just 50%.
How far off is the stock Grand Sport with average driver? FR and LR
the cross weight could be anywhere to be honest - the factory is going to generally set the car up with the same height adjusted into the spring bolt front and rear, meaning I had two full turns left on the rear bolts and almost 3/8" of adjustment left on the front from the dealer (they may have lowered it some, who knows). So, with tolerance stackups and so forth, it could be absolutely anywhere. I didn't check stock cross as I didn't care, I knew I was fixing whatever
but will say it was very unlikely to be right at 50%.Key is you have to take the time to level the car (which frankly I was really level with equal adjustments at the springs so left them even) and do the scaling
Does in interact with the rest of the alignment or ride height? As stated, ride height you set where you want it. Adjusting weight for cross should NOT affect ride height.
Last edited by CyberGS; 09-21-2010 at 03:09 PM.
09-21-2010, 02:50 PM
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Sorry I must of not made the question clear.
What did you do if anything to adjust the static weight distribution: Left to Right static weight is not mentioned , looks like your Front to Rear is pretty good already?
Curious if you added any weight anywhere to improve over factory conditions?
I understand the procedure and math behind corner balance. Just curious how far off the OEM settings were from where you ended up.
What are your final corner weights with you in the car and a track fuel load?
Don't you need to disconnect the sway bar end links to prevent it effecting the cross weighting? And then reconnect and adjust to balance the loading of the anti-sway bar?
What did you do if anything to adjust the static weight distribution: Left to Right static weight is not mentioned , looks like your Front to Rear is pretty good already?
Curious if you added any weight anywhere to improve over factory conditions?
I understand the procedure and math behind corner balance. Just curious how far off the OEM settings were from where you ended up.
What are your final corner weights with you in the car and a track fuel load?
Don't you need to disconnect the sway bar end links to prevent it effecting the cross weighting? And then reconnect and adjust to balance the loading of the anti-sway bar?
Last edited by Dan Wendling; 09-21-2010 at 02:53 PM. Reason: clarify end links
09-21-2010, 03:24 PM
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xxx
Sorry I must of not made the question clear.
What did you do if anything to adjust the static weight distribution: Left to Right static weight is not mentioned , looks like your Front to Rear is pretty good already? I used the adjuster screws on the springs to adjust the weight distribution.
Curious if you added any weight anywhere to improve over factory conditions? No, you should never have to do that, just adjust the springs until the loading is what you want it to be at each corner. Ballasting is only done if you need to add weight to make some sort of rule book weight minimum, you NEVER add weight to a car to balance it unless it is really out of whack and doesn't have an adjustable suspension. Even then, I would shim the springs until it came in v. add weight, but shimming springs is a major PITA so adding weight would be easier. Add too much and you might have perfect cross but go just as slow lugging that weight thru the corners.
I understand the procedure and math behind corner balance. Just curious how far off the OEM settings were from where you ended up. I didn't check the stock settings, I knew I was going to lower the car some and set it up right so I just did that. Because I adjusted all four corners identically I have to assume the cross was probably what I measured after lowering, which was about 53%. It is built in Kentucky so makes sense it would come ready to turn left all the time
What are your final corner weights with you in the car and a track fuel load? Don't have the numbers here at work with me but roughly each corner was right around 900 lbs with the left side about 100 lbs higher overall IIRC. Car was 3555 with me in it, 3/4 tank of gas. All four corners were pretty close to each other in weight, which is expected with a 50/50 wt distribution front to rear... They were all within 10% of each other IIRC. My road race car is more like 57% rear weight so you can really see a difference in the weights of front v. rear wheels, but left to right they tend to be within 10% of each other on that car too at each end.
Don't you need to disconnect the sway bar end links to prevent it effecting the cross weighting? And then reconnect and adjust to balance the loading of the anti-sway bar? The end links are not adjustable on the stock vehicle, so you do not disconnect them as you essentially load the bar when you reconnect them, which would affect the cross again, so I do static bars with the links connected. With adjustable links (which I will likely just make, maybe buy if they are cheap enough) you disconnect the bar, cross weight, then adjust the links for zero preload and reconnect. This is by far the best setup, but the stocker just didn't have that. My race car is adjustable of course.
What did you do if anything to adjust the static weight distribution: Left to Right static weight is not mentioned , looks like your Front to Rear is pretty good already? I used the adjuster screws on the springs to adjust the weight distribution.
Curious if you added any weight anywhere to improve over factory conditions? No, you should never have to do that, just adjust the springs until the loading is what you want it to be at each corner. Ballasting is only done if you need to add weight to make some sort of rule book weight minimum, you NEVER add weight to a car to balance it unless it is really out of whack and doesn't have an adjustable suspension. Even then, I would shim the springs until it came in v. add weight, but shimming springs is a major PITA so adding weight would be easier. Add too much and you might have perfect cross but go just as slow lugging that weight thru the corners.
I understand the procedure and math behind corner balance. Just curious how far off the OEM settings were from where you ended up. I didn't check the stock settings, I knew I was going to lower the car some and set it up right so I just did that. Because I adjusted all four corners identically I have to assume the cross was probably what I measured after lowering, which was about 53%. It is built in Kentucky so makes sense it would come ready to turn left all the time
What are your final corner weights with you in the car and a track fuel load? Don't have the numbers here at work with me but roughly each corner was right around 900 lbs with the left side about 100 lbs higher overall IIRC. Car was 3555 with me in it, 3/4 tank of gas. All four corners were pretty close to each other in weight, which is expected with a 50/50 wt distribution front to rear... They were all within 10% of each other IIRC. My road race car is more like 57% rear weight so you can really see a difference in the weights of front v. rear wheels, but left to right they tend to be within 10% of each other on that car too at each end.
Don't you need to disconnect the sway bar end links to prevent it effecting the cross weighting? And then reconnect and adjust to balance the loading of the anti-sway bar? The end links are not adjustable on the stock vehicle, so you do not disconnect them as you essentially load the bar when you reconnect them, which would affect the cross again, so I do static bars with the links connected. With adjustable links (which I will likely just make, maybe buy if they are cheap enough) you disconnect the bar, cross weight, then adjust the links for zero preload and reconnect. This is by far the best setup, but the stocker just didn't have that. My race car is adjustable of course.
09-22-2010, 02:50 AM
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corner weights
So finally getting a chance to get back to you with actual corner weights... designed a completely new suspension for my race car so been busy tonight figuring out what I am going to do for sway bars. Finally got everything tacked into place, so lots of welding to come there.
LF 904 RF 886
LR 910 RR 855
51% left weight
49.6% rear weight
50.5% cross weight
Next time I am at the track I will take my timing equipment, lay down some laps, then just reduce the cross on the fly and watch the times to see where the car comes in best. Probably won't be until next year, maybe next month if I get a chance but winter is coming soon.
For a mostly street car, again, 50% is correct for cross.
LF 904 RF 886
LR 910 RR 855
51% left weight
49.6% rear weight
50.5% cross weight
Next time I am at the track I will take my timing equipment, lay down some laps, then just reduce the cross on the fly and watch the times to see where the car comes in best. Probably won't be until next year, maybe next month if I get a chance but winter is coming soon.
For a mostly street car, again, 50% is correct for cross.
09-22-2010, 10:47 AM
#16
Melting Slicks
YAY! Someone else that knows what the adjustable suspension is actually for.
I put mine on the race car scales and balanced it about a year ago. Everybody usually just cranks away at the bolts to lower the car and never pays attention to throwing off the balance. (They're ADJUSTMENT bolts, NOT LOWERING BOLTS!)
I got mine down to .2. and it was waaaay off... 54.8, if I remember correctly. I immediately noticed a difference in entrance and exit...even on a freeway on-ramp.
Balancing the ride is one of the best mods one can do imo.
I put mine on the race car scales and balanced it about a year ago. Everybody usually just cranks away at the bolts to lower the car and never pays attention to throwing off the balance. (They're ADJUSTMENT bolts, NOT LOWERING BOLTS!)
I got mine down to .2. and it was waaaay off... 54.8, if I remember correctly. I immediately noticed a difference in entrance and exit...even on a freeway on-ramp.
Balancing the ride is one of the best mods one can do imo.
09-22-2010, 01:24 PM
#17
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They're ADJUSTMENT bolts, NOT LOWERING BOLTS!
I got mine down to .2. and it was waaaay off... 54.8, if I remember correctly. I immediately noticed a difference in entrance and exit...even on a freeway on-ramp.
Man, that car probably wouldn't even have turned left that well either with that much cross If I throw one more turn into each of the opposite corners I would be right at 50/50, say 50.2 as you note, but will tune mine to the track by times.
Balancing the ride is one of the best mods one can do imo.
Yep, and the first sign that it is the best mod one can do, no extra parts to buy or swap out and if you have a buddy with scales it's free! And all I needed: two jacks (one to jack the spring back up to unload the bolt), taking the wheel off, and a 10mm wrench.
I got mine down to .2. and it was waaaay off... 54.8, if I remember correctly. I immediately noticed a difference in entrance and exit...even on a freeway on-ramp.
Man, that car probably wouldn't even have turned left that well either with that much cross
If I throw one more turn into each of the opposite corners I would be right at 50/50, say 50.2 as you note, but will tune mine to the track by times.Balancing the ride is one of the best mods one can do imo.
Yep, and the first sign that it is the best mod one can do, no extra parts to buy or swap out and if you have a buddy with scales it's free! And all I needed: two jacks (one to jack the spring back up to unload the bolt), taking the wheel off, and a 10mm wrench.
09-22-2010, 03:10 PM
#18
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CyberGS, this is a great to read. While I might not do this myself now perhaps later, regardless having the knowledge and basic understanding is just as important. Great explanation, very easy to digest.
Thanks!!
Thanks!!
09-23-2010, 02:43 PM
#19
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No problem! This sort of information exchange is what I tend to think Forums should be for
I was fortunate in my 20s to get to work with a bunch of race car prep and builds, so I got to learn a lot about setting them up, etc and remember what it was like having no clue at the time and learning something that was pretty cool to know in the end.
Dan - forgot to answer one of your questions about alignment, it *might* affect alignment. Here is a couple scenarios:
1. Your car is at a ride height you like already and the alignment is perfect, but your cross weights are off. Assume you need to remove cross as me and others have found, as long as you go down the same number of turns on the adjuster front and rear in the cross axis, then also go up the same # of turns in the opposite axis, the weights will change at the wheels but the ride height change should be essentially zero. Because your suspension essentially didn't move, you don't need to do an alignment.
2. You lower the car the last 1/4" like I did... I am not going to redo the alignment because of this*. Arguably I moved thru the camber gain curve when I lowered it a bit, so I have a bit more static camber now, but it is going to be super super minimal change on a Corvette susp over 1/4" of motion. Also, I haven't measure this, but I assume the Vette suspension is designed enough now to have virtually no bump steer as that is something that can always be tuned way low with this dual A setup. So I don't mind a little extra neg camber, think that is better actually, so no need to realign IMHO.
3. You lower the car 1"+. Now I recommend redoing the alignment.
* I am going to do an alignment to the car, but not due to the cross weighting... I want a bit more camber front and rear... I am going to go about -1.0 deg on the front and -0.5deg on the rear based on what I have seen on GT1 Vettes, and also going to go toe out on the front.
I was fortunate in my 20s to get to work with a bunch of race car prep and builds, so I got to learn a lot about setting them up, etc and remember what it was like having no clue at the time and learning something that was pretty cool to know in the end.
Dan - forgot to answer one of your questions about alignment, it *might* affect alignment. Here is a couple scenarios:
1. Your car is at a ride height you like already and the alignment is perfect, but your cross weights are off. Assume you need to remove cross as me and others have found, as long as you go down the same number of turns on the adjuster front and rear in the cross axis, then also go up the same # of turns in the opposite axis, the weights will change at the wheels but the ride height change should be essentially zero. Because your suspension essentially didn't move, you don't need to do an alignment.
2. You lower the car the last 1/4" like I did... I am not going to redo the alignment because of this*. Arguably I moved thru the camber gain curve when I lowered it a bit, so I have a bit more static camber now, but it is going to be super super minimal change on a Corvette susp over 1/4" of motion. Also, I haven't measure this, but I assume the Vette suspension is designed enough now to have virtually no bump steer as that is something that can always be tuned way low with this dual A setup. So I don't mind a little extra neg camber, think that is better actually, so no need to realign IMHO.
3. You lower the car 1"+. Now I recommend redoing the alignment.
* I am going to do an alignment to the car, but not due to the cross weighting... I want a bit more camber front and rear... I am going to go about -1.0 deg on the front and -0.5deg on the rear based on what I have seen on GT1 Vettes, and also going to go toe out on the front.