Physics

[EVOclipse]

Just to finish and defend my physics class. when theyres body roll its DUE to weight transfer from one side to the other. if theyre is more body on one side, it effectively is getting more of that bodys weight...hence why theyre is more weight on that side.yes to some extext some weight is pushing outward due to G forces but when it doesnt escape outward it goes downward where it can. (ie something reacting back like the ground) theyre now youve gone through physics 101 RW240 style

[Layla's Keeper]

Umm........... You're not quite 25% right on that.

You see, if you put lateral g'forces (the force that causes "weight transfer) against a car, it would simply slide sideway save for one crucial factor - adhesion.

The more the tires stick, the less the car slides sideways under lateral g'forces.

Now, energy cannot be destroyed, it can only be redirected/changed into another form. The vast majority of the energy becomes friction at the union between the tires and the road (which is why tires get so hot). However, a certain amount is dissipated through the travel of the suspension - this becomes body roll.

The more energy the suspension consumes, the less that becomes friction at the tire, and the cooler the tire runs (thus prolonging its life). However, this becomes energy not spent changing the direction of the car (friction).

The amount of body roll is determined by the spring rate versus the travel arc of the suspension arms compared against the amount of lateral force against the amount of adhesion provided by the tires.

This is one of the basic tenets of chassis dynamics.

[ac427cpe]

i'm impressed that you could interpret that first post...

[EVOclipse]

ok well that explains it quite a bit better i was kinda confused just by the mainly looking at the problem. a car tilted to 1 side seems to have more weight on that side ie tire. and one with little body roll just seems to distribute the weight more evenly across both tires/sides. thats mostly what got me. it seems that the more that cars body was taking the lateral gs the more that side or tire would have to take. granted i understand the whole tire slipping and what not, but thats where i was coming from so i appreciate the chassis dynamics and suspension info now i realize that because the body rolls it allows the tires and drive train to recieve less load because the spring is taking it and sending it back. so thanks i wish more people could give better answers instead of justtrying to put theyre dicks on the table to measure. more people would probly use the board if they didnt worry about oh well u dont know how to drift u must be stupid or u dont know this ure stupid. but then again if everyone were as good as the moderators then we wouldnt have any moderators. thanks

[R.W.240]

Straight from Carrol Smith

Lateral Load Transfer =

Acceleration (yes its an acceleration) x Weight x CG height
____________________(divided by)___________________
Track Width


1) That Shows that spring rate has very little to do with smooth road weight transfer

2) The energy goes back into the vehicle? as what? hopes and dreams?

3)Now... Heres the kicker: no body called me on the little peice of trivium that with coilovers your CG will usually be lower. hrrm... low CG equals less weight transfer... therefore coilovers will transfer less weight... hrrmm... I just completely owned myself and your "energy going back into the vehicle theory is still nowhere to be seen...

EVOclipse... way to show me how physics works.

[Layla's Keeper]

Yes, weight transfer itself is a function of COG versus weight versus force versus width.

It basically boils down to the idea of a pyramid versus a pillar. A short structure with a wide base with more weight down low will have less of a chance of "toppling over" than a tall structure with evenly distributed weight and a narrow base.

However, body roll is still a function of adhesion v lateral g's v suspension geometry. Weight transfer is a natural byproduct of the body changing its attitude on the suspension.

[R.W.240]

Originally Posted by Layla's Keeper

However, body roll is still a function of adhesion v lateral g's v suspension geometry Weight transfer is a natural byproduct of the body changing its attitude on the suspension.

If that were true bodyroll would not be dependant on spring rate, which, it obviously is. Weight Transfer on the other hand is not dependent on spring rate. Weight Transfer comes with or without bodyroll. Body roll can do nothing to weight transfer other than raise the CG and change roll center location.

[NSX-R-SSJ20K]

there's too much crap involved with friction and why a car slides blah blah blah best not to talk about it cuz your head will hurt

[drftk1d]

Originally Posted by NSX-R-SSJ20K

there's too much crap involved with friction and why a car slides blah blah blah best not to talk about it cuz your head will hurt

that means your brain is working