Suspension Theory/Chat Thread

[Highrev1]

There are many ways to make an ideal setup...it depends on what you are using your car for? Did you mean MAX Track handling?

[Sirbelch]

Originally Posted by LucasBlack

i
- with the realization that with compression there is an increase in neg. camber, would it be more advantageous (strictly in regards to contact patch size) to run a setup that allows less compression so as not to bring forth more neg. camber while braking?

I think it would also be advantageous, in terms of braking, to run a stiffer front suspension to help resist to much weight going to the front tires and overwhelming the tires and losing traction. Also, a stiffer front suspension would keep some weight over the rear tires which will increase the over all grip of all 4 tires which will decrease stoping distances.

[LucasBlack]

Originally Posted by Sirbelch

I think it would also be advantageous, in terms of braking, to run a stiffer front suspension to help resist to much weight going to the front tires and overwhelming the tires and losing traction. Also, a stiffer front suspension would keep some weight over the rear tires which will increase the over all grip of all 4 tires which will decrease stoping distances.

sounds good. but here's a thought, as much as we can make the front susp. undergo less compression, could we also stiffen the rear so that it allows less expansion under braking/frontal weight transfer? and then with that, we could keep the front susp. somewhat softer in terms of our FWD setup and with everything we've covered in making sure to allow for both tires to still be able to be planted while turning.
...hhhmmm..less compression equals not enough compliance for cornering traction? discuss amongst yourselves! :smile:

[Sirbelch]

Originally Posted by LucasBlack

sounds good. but here's a thought, as much as we can make the front susp. undergo less compression, could we also stiffen the rear so that it allows less expansion under braking/frontal weight transfer? and then with that, we could keep the front susp. somewhat softer in terms of our FWD setup and with everything we've covered in making sure to allow for both tires to still be able to be planted while turning....hhhmmm..less compression equals not enough compliance for cornering traction? discuss amongst yourselves! :smile:

[LucasBlack]

Originally Posted by Sirbelch

sweeeeeeeeeeeeeeeeeeeeeeeeeet

[Highrev1]

Originally Posted by Sirbelch

Also, a stiffer front suspension would keep some weight over the rear tires which will increase the over all grip of all 4 tires which will decrease stoping distances.

As for Weight distribution that can all be adjusted when the car gets corner weighted...So Adjusting dampers for that is not an ideal thing to do. GENERALLY you would be surprised how small a Front sway bar can be run up front as long as teh spring rates and dampers are up to the task.

[LucasBlack]

Originally Posted by Highrev1

As for Weight distribution that can all be adjusted when the car gets corner weighted...So Adjusting dampers for that is not an ideal thing to do. GENERALLY you would be surprised how small a Front sway bar can be run up front as long as teh spring rates and dampers are up to the task.

in a strange/somewhat artificial/can't-believe-i'm-using-this-as-evidence kinda of way, i can attest to that statement because of tuning i've done......on forza motorsport. i'm a huge dork.

[Highrev1]

Originally Posted by LucasBlack

with the realization that with compression there is an increase in neg. camber, would it be more advantageous (strictly in regards to contact patch size) to run a setup that allows less compression so as not to bring forth more neg. camber while braking

This number can only be found out with testing and personal preference. Do you more to gain from the additional -camber?

[LucasBlack]

Originally Posted by Highrev1

Do you more to gain from the additional -camber?

uuuumm......i dunno what you were trying to say.

[aki]

Originally Posted by Skylinegtr06

Anyone running an ideal set up for their Si? Can they share their set up?

Problem is, there are so many variables--and part of it is preference.

One example: W/ FWD most people's goals are to get rid of dastardly understeer. Having softing front sways means the car rotates better in corners, and potentially gives more traction up front. Downside is that steering responsiveness goes down, and you have to turn in a little quicker. For some that trade-off is worth it, for others it isn't. You could also have a toe out to the rear--but the downside to that is it can impact straightline stability, making it more dangerous for a person not familiar with the limits of the car.

There's no real one-size-fits-all because in part the "ideal" setting is what the driver is most comfortable w/ in pushing to the limit. Slight understeer is supposedly ideal (was it Carroll Smith who said that?), but some prefer neutral/slight oversteer, especially out of the exit of a turn.

[LucasBlack]

Originally Posted by aki

Problem is, there are so many variables--and part of it is preference.

One example: W/ FWD most people's goals are to get rid of dastardly understeer. Having softing front sways means the car rotates better in corners, and potentially gives more traction up front. Downside is that steering responsiveness goes down, and you have to turn in a little quicker. For some that trade-off is worth it, for others it isn't. You could also have a toe out to the rear--but the downside to that is it can impact straightline stability, making it more dangerous for a person not familiar with the limits of the car.

There's no real one-size-fits-all because in part the "ideal" setting is what the driver is most comfortable w/ in pushing to the limit. Slight understeer is supposedly ideal (was it Carroll Smith who said that?), but some prefer neutral/slight oversteer, especially out of the exit of a turn.

i personally can't see how a car that leans more towards understeer can be quicker.

- overall, i think about it like this:
a car that tends to oversteer more is a car that has an allowable range of rotation. now the driver then needs to determine how much of that range they feel is necessary for turn by turn.

while a car that tends to understeer has a decidedly smaller allowable range of rotation. therefore i see this as a limitation to the necessities of rotation determined by the driver.

[Sirbelch]

FWD RWD AWD every car needs some rotation in order to handle at its best. Tires make the most amount of grip with a little bit of slip. With undsteer, only the front tire slip. With oversteer, the rear tires slip. With proper rotation (small amout of oversteer) all four wheels slip around an axis. Four wheels at their maximum grip level will ALWAYS grip more than 2, just ask anybody on a bike. Rotation is needed for a good handling car. Even the NASCAR boys know that "a loose car is a fast car," (to a point of course).

[Highrev1]

Harry Hogge: When the rear end's loose, the car's fast. Loose is fast, and on the edge you're out of control.

[LucasBlack]

Originally Posted by Highrev1

Harry Hogge: When the rear end's loose, the car's fast. Loose is fast, and on the edge you're out of control.

Days of Thunder.

[Sirbelch]

Originally Posted by LucasBlack

Days of Thunder.

Classssssssic.

[Highrev1]

Is she running loose or tight? A turn here, take some wedge out, we'll win some races!!!!

On another note did you know 15gR = (mph)2

[Sirbelch]

Originally Posted by Highrev1

On another note did you know 15gR = (mph)2

What is that?

[Highrev1]

I was reading this site today and it said

"There is actually a formula to compute the fastest path and speed through any corner. It's 15gR = (mph)2, where R is the radius of the turn, and g is a measure of the grip of your tires."

I thought that was pretty cool....You could in theory mapoput exactly max speed on a road course through each turn...and then try to accomplish that or even beat it But see then again I don't fully agree with this at all...

[Sirbelch]

I don't know if it the right equation, (nor would i, i'm not an engineeer) but i do know some engineers and this can be calculated. Of course this equation does not include wind speed/direction, temperature, type of car (and every part/dimension on said car). It is a simple equation for first year physics students. (thats still more than me, i've only had on semester some 8 years ago)

[Highrev1]

I just don't think it works cause tires are fastest at like 5% slip angle and that doesn't take any of that inot account...