oops Oversteer

**Chad97z** · 09-18-2007, 09:56 AM

I just got some new tires, and a new alignment. It feels real good around town and its very nimble and the car feels lighter and it turns so much more "on a dime" but at highway speeds, it takes a bit of concentration to keep it straight. I find myself having a tendoncy to oversteer it. If I just barely touch it, it moves left or right. So it needs to be dampened. These are the settings I have now. I specifically asked for 0 degree's Camber because the car normally has a tendoncy to follow a groove in the road.. But now, that is totally gone. So I hope you don't tell me I need to make the camber more negative to eliminate oversteer.

However, I did notice that my drivers side caster is more positive than the passenger side and from what I see online, it's best to have the passenger side a bit more positive because of the driver sitting in the car most the time. So if I just increased the caster on the passenger side to about 5.3 degree's would that solve the oversteer problem?

**5.0THIS** · 09-18-2007, 11:30 AM

You dont need the negative camber, but it wont handle as good without it. Changing your castor a half degree isnt going to do much.

**Chad97z** · 09-18-2007, 12:40 PM

So why do people say the passenger side caster should be a little more positive than the drivers side? Isn't "caster" just the wheels amount of force or ability to swing back to center on its own after you make a turn? If so, then why have one side more than the other? And so what would you do to try and increase understeer? Do you think after the tires wear some, the oversteer may disipate? It's not much oversteer, just a little on the highway, so I'm not used to it.. I may get more used to it soon. I guess I just need to read more. My gosh. I'm reading this really large document on troubleshooting my air bag system. Haha. It never ends.

**5.0THIS** · 09-18-2007, 02:17 PM

You're using the term understeer and oversteer incorrectly. It doesnt mean what you're talking about. If you want, go look up more detailed descriptions, but in layman's terms, understeer is a "push", or a lack of front grip in a turn (like in a front wheel drive car when you turn too fast). Oversteer is a lack of rear end grip during a turn, or a "loose" condition (like in a turn in a rear drive car, and you hit the gas and the rear end slides out. That would be power induced oversteer). Neither of these conditions applies to driving in a straight line.

The condition it sounds like you're describing is a car that either wanders, or darts around. Now first off, with a 275 width front tire, these cars are going to wonder on some pavement, no matter what your alignment is... just the nature of running such a wide tire up front, you catch all the grooves and ruts.

Caster, simply stated, is the front or rearward angle (relative to vertical) of the spindle, from upper ball joint to lower ball joint, when viewed from the side. When people run more on the passenger side, they're just trying to compensate for the driver's weight. In this case, I wouldnt be worried about your castor.

First off, get some negative camber in it. With the tires perfectly vertical, your contact patch is 100% on the road, so the tires are going to grab more (which they dont need to do when going in a straight line!). The whole idea of a bit of negative camber is that when you turn, the outside front tire in that turn will lay over. The negative camber makes it so that the tire rolls over to it's full contact patch, for maximum grip. If there's no negative camber to start, then the tire will fold over on it's sidewall, and lose grip.

Second, put some toe in in it. With zero toe, the car is going to wander, plain and simple. We're talking tenths of a degree here, but a little makes a big difference in a street car.

**Chad97z** · 09-18-2007, 04:42 PM

ya, maybe I am using oversteer and understeer incorrectly. But I do not have 1 smallest amount of catching the groove or rut in the road. The tire is perfectly flat. I think the catching the rut becomes noticable when the camber is not at 0. Due to the wide the the tires, when we are not 0 degree's there is a ton of variation in pressure on the tire from the outside compared to the inside.. Thus one side (in or out) will take to the groove. With neg camber, the inside of the tire takes to the groove. With positive camber, the outside of the tire takes to the groove. So thats why I wanted it flat. And to be totally honest with ya, the car totally isn't loosing any grip in a corner right now.. It turns much faster than what it did before and it feels lighter.. So everything is pointing to better handling with 0 degrees, or maybe its just the software compound of the tire.. I dont know but it turns on a dime now. And plus see if I am right here. Lets say you turn left real hard. The car leans right. So the driver side effectively goes up while the passenger side goes down. Well, just the basic design of the suspension allows the drivers tire to pivot down and create more positive camber while the right side leans down, the wheel moves up and creates more negative camber. So its nearly auto adjusting for body sway.. But honestly, I have a 35mm anti sway bar and my car is lowered.. My car is really flat in a curve.. So if the car is flat, there isn't much variance anyway.. plus I don't race on a slalom. So, really, I'd like to avoid putting any camber in it.. Maybe some tow in, but that kills your tires. I think maybe just -.1 camber may be ok. I guess they will have to put some neg camber in it to create some tow. Because both camber and tow is 0. And turning the outter tie rods 1 turn would be way to much. So they are going to have to slide the lower arm out. ugh..

**Chad97z** · 09-18-2007, 05:31 PM

ok.. after I said all that.. I just drove it again and its not really bad at all. Its just very sensitive in the steering at highway speeds. BUt before the new tires and alignment.. I dont know what happened, but the steering was very very stiff. Now it feels normal. I've never had my car so reactive to steering before. I think maybe I will just have to change the way I think abut driving my Camaro. Its odd that it has changed that much, but its remarkably a different drive and a different ride. It rides so much smoother. Like a luxury car. Haha I knwo these tires are softer, but I think a 0 degree camber also gives the front end a little more spring. jsut slightly

**5.0THIS** · 09-18-2007, 06:36 PM

The alignment you have still isnt great, and not really conducive to great handling IMO

**Chad97z** · 09-18-2007, 08:36 PM

ya I'll prolly have them change the camber to -.1 I have seen the recommendation on this website and says -.5 camber and tow as .03. But I dont want that much negative camber. It creates that veering effect over ruts and seems in the road. And I extremely dislike that.