This might be a dumb question but if adding more tire to the back creates more understeer, does adding a wider tire on the front give it a little more oversteer? I don't really know what under/oversteer means I'm assuming that understeer kinda pushes you through corners and oversteer kinda sucks you into the turns?
Heh, oversteer scares the passenger, understeer scares the driver.
Technically, oversteer is when the car turns more than the steering input you gave it should make it turn. Understeer is when the car turns less than your steering input should make it.
Oversteer is usually referred to as "fishtailing" or drifting. Understeer is "plowing". In Nascar terms, you're talking "tight" or "loose".
Or, the best way I've seen it put: Understeer is when you hit the wall with the front of the car. Oversteer is when you hit the wall with the back of the car. Horsepower is how fast you hit the wall, and Torque is how much of the wall you take with you.
Most production cars are set up to understeer. This is usually safer, as the steering gets heavier as you approach the limit. It also prevents people who aren't trained to deal with evasive driving maneuvers(sp?) from spinning out as they wildly overcorrect.
Tire size is just one component of the handling dynamic of the car. Putting a wider tire up front should reduce understeer, however, you're also decreasing the PSI between the tire and the road, and potentially decreasing traction (this is why skinny tires work better when roads are slick). There's a lot of other variables involved, biggest being the weight distribution of the car and the relative spring rates of the front and rear suspension. Swaybars are one of the easiest ways to adjust that springrate, which is why they're used as a tuning tool to dial out undesireable under/oversteer.
To complicate it further, there's entry over/understeer, mid-corner over/understeer, exit over/understeer. A car might understeer on corner entry, but oversteer on exit.
I could go on, but I'm sure if you're interested, you'll post questions, hahaha.