Suspension Brakes 1st Gen Spring Rates

You did not say what you wanted out of your car. I have TSW V-3s with 400 lbs springs all around, and a 19mm bar. I can get my car to oversteer by backing off the throttle. For just autocrossing I have a set of 500 lbs springs. They make the car turn right now. I am a beginning autocrosser and haven’t been using them because I need to get some experience before stepping up to fly into the turn lift and plant the throttle again. I hope to get there but I can’t drive the car when it is so tail happy. With 400 lbs springs the car is very predictable.

 

This may sound crazy but you might want to stick to the stock springs or a only mildly harder one that gives a modest drop (1/2 in) then focus on the dampening. You're always gonna have some body roll and some front-end dive but if you slow the rate of those effects (better shock/struts) your turn-in and control will improve markedly and you can still use the car on a DD basis without beating yourself up. A little bit of swaybar in the back (19mm) will help turn-in. Just remember you get that extra turn in at the cost of rear grip.

 

What makes you think the inside rear wheel needs to be on the ground to be fast?

 

A legit one.....:rolleyes5:

I was just wondering what you know that the professional teams don't cause you will see that in just about every single front wheel drive race car. The rear tires don't have a lot to do on a front wheel drive car.

The lifted inner rear tire is an indication that the front sway bar is too small to keep the rear on the ground. The problem with that is that as soon as you increase the front bar to compensate for this you start inducing understeer.

Suspension set-up is a compromise. What do you want... great turn in, a bit of understeer or an inner rear tire on the ground.

 

:confused5::confused5:

I've never seen a prepped Civic going around a corner that didn't look like a dog taking a piss.

 

Here is a nice link to a fairly basic description of what different suspension settings will do.
rFactor-League.com Formula 1 Racing Simulation

 

Sorry, I saw that you were DD'ing the car and "getting" serious about AutoX. Hence my advice.

I will keep my uneducated input to myself.

 

The biggest single thing to improve the handling of a MINI or any other limited travel strut suspension car is to keep the car off the bump stops. To do that you need enough spring. The stock set up uses soft springs to be compliant over bumps. The shock forces are often more than the forces of the springs, and one of the differences between the more expensive shocks and the less expensive shocks is the more expensive ones are digressive. Shocks affect handling at low shaft speeds. Shock absorber shaft velocity or speed is fast over bumps and slower in roll. The force increases at a linear rate on most shocks. Digressive shocks high forces at low speed, but do not increase in a linear rate. The advantage is the ride will not suffer as much. Picking the inside rear wheel off the ground is the result of the car reaching the limit of rear roll stiffness. The rear bar forces are exceeding the weight on the tire. Having all four tires on the ground is better. A tire can’t develop any traction if it is up in the air. How many F-1 cars have you seen cornering on three wheels? To increase the rear roll stiffness (tune the car looser or to over steer) use stiffer rear springs. A tire will develop a specific amount of traction. You can use the available traction to accelerate, brake or corner. If you use more than one at a time the available grip is divided between the two. Front wheel drive cars have the vast majority of the weight on the front tires, and work the front tires a lot more than the rear tires. To reduce the cars tendency to under steer increase the rear roll stiffness. That is why it is a popular modification to increase the rear bar size. If you want to go really fast on a autocross course get the car loose enough that the car turns with very little turning of the steering wheel. Less turning makes more traction available to corner.

 

Sorry but we are all trying to help. Spring rates are not the only thing you need to consider. Did you check out the link I posted? Yes it is from a PC race sim, but the physics are real world. It has some of the best info on what different suspension setting will do to a car. Simply wanting to get the tire back on the ground is not going to make you faster. You say you have the rear bar set at the max, this is also contributing to the tire coming off of the ground.

Like I said before, suspension set-ups are all about compromises.

 

I haven’t tried a lot of different rate springs on my car. Dr. Mike picked out mine, and I have been very happy. I mainly adjust the balance with front rebound, and rear ride height. I do not change it much or very often. The car is very predictable and easy to drive. Given my autocross skill level I think I am better off concentrating on my driving and not adjusting on the car. Spring rates are a combination of personal feel, driving style, and keeping the car suspended. Once you have achieved keeping the car off the bump stops the next step is balancing the handling with roll stiffness. Keeping the rear wheel on the ground does make a difference. What the circle track racers call wedge is affecting the handling. A tire will develop more grip on softer springs, but the affect is marginal in comparison to the drivers sense of control. Some of us are more aggressive with the car and like higher spring rates.

 

For autox you want to set the car up steady state loose so my rule of thumb for a FWD car for autox set up is usually about 1/3rd more rear spring then front. For track unless you enjoy driving sideways with your foot in it to keep it from coming around you'll wanna calm it down. I'm doing an R56 with square spring rates in a few weeks and a big rear bar for track, the customer doesn't do particularly well with a loose car so we're gonna try to make it still handle well but be a touch on the tight side. I'll see how that is and adjust as needed. Key to autox is you want the thing to transition very well and ALWAYS turn. It's tricky to make a car have a load of front end grip but not want to point backwards in transitions. Your doing the right thing running AST's thought!