Not true. On street tires cornering grip increases as you increase tire pressure up to a point. Increasing pressure in the front relative to the rear reduces understeer, while increasing rear pressure relative to front increases understeer/reduces oversteer.
oops! You're right, I was thinking he was trying to eliminate Understeer, which is what most people want. Didn't read it clearly enough.
Why wouldn't you want to be able to break the car loose and induce oversteer at will?
__________________
Woe to him who builds his palace by unrighteousness,his upper rooms by injustice,making his countrymen work for nothing...Does it make you a king to have more and more cedar?Did not your father have food and drink?He did what was right and just,so all went well with him. He defended the cause of the poor and needy,and so all went well...But your eyes and your heart are set only on dishonest gain,on shedding innocent blood and on oppression and extortion. Jer 22:13, 15-17
To answer some of the questions and comments, here you go. First, I am not an expert in this matter by any means. This is the first car I have ever upgraded the suspension like I did. I did upgrade both the front and rear suspension with shocks/struts (non-adjustable), springs, and anti-sway bars. In addition to the brakes and adjustable panhard bar. I am currently running 20" wheels with 255/40ZR20 tires (plan on going up to a a 275/35ZR20 soon).
I am not saying that braking rearend loose is a bad thing (nor necessarily a good thing), I am just wondering if it is normal. I must admit, there was certainly a bit of the adrenelyn thrill factor as the car tried to go sideways under all that power. I am not saying I was not able to control the car, for although I have not gone to a performance driving school (which does seem like both a good plan and lots of fun), nor am am I a race car driver, but I am a skilled driver. I am smart enough and skilled enough to know when the car is getting away from me, and in such times, the first thing I do, is to take my foot of the vertical right pedal.
I guess the true question would be, with a suspension kit, how does it corner better? What part of the cornering is improved with the upgrade? Like I said, I am possibly expecting too much from the upgrades. I am beginning to wonder what was the purpose of the suspension upgrades? I know I wanted the car lower for both looks and lower center of gravity. However, the Salenn kit (Eibach Pro) is not too aggressive, so the lowering is not as noticeable as the Eibach Sportline. For even though I have 20' wheels, I still have and inch to and inch and a half clearnce between the body and tires. My purpopse for the suspension upgrade was for just that...an upgrade from the sotck suspension. I have been told the such an upgrade will improve performance, speicifically in cornering, but it has never been fully explanined to me exactly what part of cornering is improved. Assuming the rearend braking loose under hard acceleration in shapr corners is normal and possibly even desireable, what else is there to cornering that is now improved? I would hate to think I spent so much time, energy and money on "upgrades" that do not exactly do anything besides add to the looks and give me bragging rights...for that would be bad.
I hope I covered all the questions and comments, if not, refresh my memory and i will address those particular questions/comments. Thanks for all the adivce, I am rapidly learning more about the mechanics and engineering of my car than I actually thought I would. Maybe I should have paid more attention in Auto Shop way back in high school....hhhmmmm.
The reason your tires broke loose is because the total possible grip was exceeded. This may sound obvious but their is more to it than that. As you're driving there are basically three forces acting on the tire--lateral (cornering) and longitudinal (acceleration and braking), and gravity. If you assume that the total available grip=100%, any combination of lateral and longitudinal forces exceeding 100 will cause loss of traction. In other words, if you are cornering at 75% of the tire's capacity then there is 25% remaining for acceleration. Throttle modulation is one key to putting down power exiting a turn, especially with a torquey engine. A smooth application of power will allow the weight of the car to transfer rearward, essentially shifting the force of gravity and forcing the tires into greater contact with the road. Stomping the throttle in mid turn will apply an instantaneous force to the tires before weight has tranferred causing loss of grip. Getting back to your original question, a performance suspension limits extraneous body movement-brake dive, bodyroll, etc. and also shifts roll stiffness rearward so that there is less inherent understeer, the advantage being that cornering forces are spread more evenly among all four tires (ie. neutral handling) instead of the fronts bearing the brunt of the load. A neutral handling car requires some adjustment in driving style but the overall limits are higher.
To answer some of the questions and comments, here you go. First, I am not an expert in this matter by any means. This is the first car I have ever upgraded the suspension like I did. I did upgrade both the front and rear suspension with shocks/struts (non-adjustable), springs, and anti-sway bars. In addition to the brakes and adjustable panhard bar. I am currently running 20" wheels with 255/40ZR20 tires (plan on going up to a a 275/35ZR20 soon).
I am not saying that braking rearend loose is a bad thing (nor necessarily a good thing), I am just wondering if it is normal. I must admit, there was certainly a bit of the adrenelyn thrill factor as the car tried to go sideways under all that power. I am not saying I was not able to control the car, for although I have not gone to a performance driving school (which does seem like both a good plan and lots of fun), nor am am I a race car driver, but I am a skilled driver. I am smart enough and skilled enough to know when the car is getting away from me, and in such times, the first thing I do, is to take my foot of the vertical right pedal.
I guess the true question would be, with a suspension kit, how does it corner better? What part of the cornering is improved with the upgrade? Like I said, I am possibly expecting too much from the upgrades. I am beginning to wonder what was the purpose of the suspension upgrades? I know I wanted the car lower for both looks and lower center of gravity. However, the Salenn kit (Eibach Pro) is not too aggressive, so the lowering is not as noticeable as the Eibach Sportline. For even though I have 20' wheels, I still have and inch to and inch and a half clearnce between the body and tires. My purpopse for the suspension upgrade was for just that...an upgrade from the sotck suspension. I have been told the such an upgrade will improve performance, speicifically in cornering, but it has never been fully explanined to me exactly what part of cornering is improved. Assuming the rearend braking loose under hard acceleration in shapr corners is normal and possibly even desireable, what else is there to cornering that is now improved? I would hate to think I spent so much time, energy and money on "upgrades" that do not exactly do anything besides add to the looks and give me bragging rights...for that would be bad.
I hope I covered all the questions and comments, if not, refresh my memory and i will address those particular questions/comments. Thanks for all the adivce, I am rapidly learning more about the mechanics and engineering of my car than I actually thought I would. Maybe I should have paid more attention in Auto Shop way back in high school....hhhmmmm.
No, in a RWD vehicle, if you lift completely off the throttle, you can induce snap oversteer which IS uncontrollable and spin during high speed cornering. You either want to hold the throttle or increase th ethrottle to power out.
In FWD cars, you lift to reduce understeer.
__________________
Woe to him who builds his palace by unrighteousness,his upper rooms by injustice,making his countrymen work for nothing...Does it make you a king to have more and more cedar?Did not your father have food and drink?He did what was right and just,so all went well with him. He defended the cause of the poor and needy,and so all went well...But your eyes and your heart are set only on dishonest gain,on shedding innocent blood and on oppression and extortion. Jer 22:13, 15-17
Power Oversteer and Lift-off Oversteer
The more tractive force we apply, the larger slip angle is created in the driving wheel. Therefore, for the RWD cars, we can use the throttle to control the degree of oversteer. When the car is entering a corner too fast and seems likely to run wide, we can correct its direction by increasing the throttle (not to do this before reaching the mid corner !), then the car oversteers. If we find the correction is too much, we can ease the throttle and let the car returns to neutral steer or even mild understeer, depends on the suspension design and weight distribution.
Only RWD cars or rear-biased 4WD cars can do this ! In the same situation, the driver in a FWD car has nothing to do other than easing the throttle, slow down the car thus reduce the centrifugal force, and hope the car can overcome the corner. There are many disadvantages :
You lose time during slow down.
You lose engine rev during slow down, thus the engine takes longer to rise back to the useful power band once you exit the corner.
Very often, if you miscalculate, you are unlikely to have sufficient road ahead for you to slow down, especially in tight corner.
.
Therefore we always say RWD car is superior than FWD car in handling. There are, however, some well-sorted front-driver (especially some GTi) can play "lift-off oversteer", which is actually the reverse of "power oversteer" - a degree of permanent oversteer is built into the car but is only accessible when the car is pushing to the limit and with throttle disengaged. Step down the throttle again will reduce the oversteer and even back to understeer. Anyway, obviously this is still not as controllable as "power oversteer". While power oversteer can extract a lot of oversteer - actually depends on throttle - lift-off oversteer is rather limited, simply because it is impossible to build a lot of permanent oversteer to the chassis without deteriorating handling in lower speed or straight line.
Once again I have to emphasis that the power oversteer must be highly controllable by the driver, otherwise the car may lose control and spun. To make a good power oversteer car, the secret is to match the power and cornering limit perfectly at the speed concerned.
__________________
Woe to him who builds his palace by unrighteousness,his upper rooms by injustice,making his countrymen work for nothing...Does it make you a king to have more and more cedar?Did not your father have food and drink?He did what was right and just,so all went well with him. He defended the cause of the poor and needy,and so all went well...But your eyes and your heart are set only on dishonest gain,on shedding innocent blood and on oppression and extortion. Jer 22:13, 15-17
