Understeer and oversteer

Understeer= when the front of the car tends to "plow" straight ahead even though the wheels are turned.
oversteer= the front wheels are turned slighlty and the rear of the car looses traction and wants to come around faster then the front. Like doing donuts.
 
Understeer is when you go into a corner and turn the steering wheel and the car keeps going straight. (extreme example)
Oversteer is when you go into a corner and turn the steering wheel and the front end turns immediately as the back end nicely comes around you a couple of times with you as the center of the circle. (extreme example)
 
If anybody has oversteer when braking in a turn it's because the brake pressure surges in the rear brakes for a split second. We sell a valve called an LBS valve that prevents this. You notice a big difference from installing this valve in your brake line.
 
You use brakes going around corners?

If you are smart you do. I'm not talking about putting around town to an ice cream shop or something. In any "spirited" driving, you brake as you head into a turn, this is where you can lock up the rear... then you accelerate after you hit the apex of the turn. Slow in, fast out. Improved braking lets you enter the turn faster with more control, and get a much faster exit.

What else would I have meant? Are you going to experience any oversteer turning into your driveway at 6 mph??
 
Rear brakes just apply faster in the rear if they are drum disc. You can get an adjustable proportioning valve and fix that or back off the adjustment.

Yeah, a proportioning valve is a band-aid at best. You reduce the brake pressure in the rear... but then the front brakes have to compensate causing more brake fade, wear, and less balance. By delaying the spike in the rear brakes you can even run higher than stock pressure to the rears without locking them up, the brakes still function like how they were meant to, you don't overwork the fronts (which are what matter the most)

An adjustable proportioning valve is pretty much jerry rigging it all.
 
back to oversteering and understeering.... are both of these bad? i would think understeer is but is over steer? the reason i ask this is because i just put a sway bar on the rear of my car and i was reading in another forum that you install one to fix one or the other...

also, on a site i was reading about balancing out the suspension front to rear... how do you know if your balanced? i have 5 leaf mid eye rear with shorter shakles, sway bar and kyb shocks; front i have 1 1/8 sway, kyb shocks, soon to have shelby drop and 1" 160lb drop springs. is that balenced?
 
Depends on your driving style, although I don't know many that like understeer, honestly.

Oversteer (moderate amount) is believed to get you around corners faster because you can "steer" with the rear end (in effect). Some like it . . . some don't. It's NOT for the feint of heart.
 
19mustang65 said:
back to oversteering and understeering.... are both of these bad? i would think understeer is but is over steer? the reason i ask this is because i just put a sway bar on the rear of my car and i was reading in another forum that you install one to fix one or the other...

also, on a site i was reading about balancing out the suspension front to rear... how do you know if your balanced? i have 5 leaf mid eye rear with shorter shakles, sway bar and kyb shocks; front i have 1 1/8 sway, kyb shocks, soon to have shelby drop and 1" 160lb drop springs. is that balenced?
Ideal is neither under nor oversteer. You want neutral steering, which means that you can create under or oversteer as the situation requires through chassis or throttle adjustment.

I don't know what you read about balancing, but during fine tuning you weigh each corner of the car. You want to adjust the weight distribution to your advantage. This is also called weight jacking. It's very common for quarter milers or circle track guys to do it, but road racers can also benefit.

Now let me recommend you purchase and read "How to Make Your Car Handle" by Fred Puhn, which I just plagiarized. :D Neutral steering isn't as simple as a list of parts. It will include many other things including alignment specs, tires and pressures, weight balance... There's a lot of work that goes in to making your car handle as well as possible - I don't think there's a quick answer, unless you decide to pay someone to do it for you.

Lowering the car, stiffer springs, heavier sway bar - those changes will generally improve your car, but I think a planned and systematic approach will give the best results. What I've seen a lot of people recommend is to drive the car and make changes based on how the car drives. Also, it's easier to learn driving a stock understeering, underpowered car than a twitchy, 700 horse monster.

Food for thought. Good luck. :)