Pic request - F30s with H&R Sport Springs, MSport or M Performance Suspension

[fredsoowk]

Not bad... i like the last bit.. "Its overall that count"...

its about the balance/ratio of front and back traction that you have. i can see that you are about half way into the journey of understanding suspension logic. tyres plays a big role, but so do suspension geometry.

I could make your semi slicks feel like crap if i alter your geometry.. i could also make your normal tyres feel almost as good as you semi slick at medium speed corners playing with the geometry and tyre pressure. (of course .. just almost lah)

if a car need to slow down too much entering a corner and have to wait before powering out..means you have more rear traction than front on traction. now..

home work 1.0 .. what would you do to balance or to correct this?? assuming you can alter shock setting, spring setting, ride height, roll centre, alignments, tyre pressure.. but same tyres??

guys ..i am no belittling (if there is such a word) anyone.. but i truly believe, if i can share with you this knowledge, it will make all our lives as car enthusiast more meaningful. Quoting one of the veteran of motorsports of malaysia, Mr. On Kah Beng from lotus.. "its a black art"

Yeah that's what I meaning to say. When u are at Sepang it's not necessary high HP car can do timing. A well balance car can do timing faster than a high HP car.

Camber settings, toe settings, ride height, soft hard settings, tire pressure, and most important driving style to accommodate all those setting can make your car in and out of the corner fast. Overall settings in the most important.

 

[willy5]

less body roll means less grip you nit wit!!

Cocky!

Reducing body roll works up to a point, see last paragraph, this is taken from the web, there are many other sources too

[h=2]Roll Resistance[/h]Anti-roll bars are used to reduce body roll during cornering. They add to the roll resistance of the suspension springs for a higher overall roll resistance Because the primary purpose of the spring is to maintain maximum contact with the road surface over imperfections, we must settle for the roll resistance provided, and it is rarely enough. The anti-roll bar adds to the roll resistance without resorting to an overly stiff spring. A properly selected anti-roll bar will reduce body roll in corners for improved cornering traction, but will not increase the harshness of the ride, or reduce the effectiveness of the tire to maintain good road surface contact.
So, how does limiting body roll improve handling? The suspension system geometry (the lengths and connecting points of its parts) of a street car is designed to keep the bottom of the tire parallel with the road for maximum contact patch. At rest, the car's suspension has a particular geometric relationship to the road surface. Body roll changes that relationship, and reduces the suspension's ability to keep the tire parallel to the road.
During body roll, the car body is no longer parallel with the road, and neither is the suspension geometry. Even though the suspension allows the wheel to be somewhat independent from the body, the high cornering forces, and resulting large body roll of a factory car, on the track take the suspension close to its limits where it affects the angle of the wheel.
Large amounts of body roll cause the wheels to tilt away from the corner which lifts the edges of the tire and reduces the contact patch size. While this can be compensated for by having the wheel purposely tilted inward to start (adding negative camber), there is a practical limit to this which is not enough in most cars to compensate entirely for the body roll. The anti-roll bar reduces the amount of body roll, and therefore helps to maintain as much of the contact patch as possible.


As with all good things, more is better only to a point. Because the anti-roll bar connects the left and right sides, this reduces the independence of independent suspension. Too stiff a bar, and you can cause too much loss in the ability of the left or the right wheel to independently respond to road surface imperfections. The purpose of suspension is to maintain maximum tire contact with the road. The purpose of independent suspension is to allow the left and right wheels to each seek that contact separately. The left wheel may need to be going down when the right needs to be going up. If they were tied together as with the old floating rear axles, one or both of the wheels is not achieving maximum contact. In fact, too stiff an anti-roll bar can actually cause an inside wheel to lift completely off the ground during hard cornering.

 

[tIANcI]

Willy5 ... Hehehe ...

 

[alantiong]

willy.. I am cocky and I know it..

the article that you posted is an after fact and function of Anti Roll. this is to maintain as much lateral position vs centrifugal force of the car from wanting to flip. means also less weight to cause friction of tyre surface to road surface.

Basic Mechanical Dynamic - total grip/friction on the road is sin(angle of roll from lateral axis)xtotal vertical acc x mass of car. so if there is no transfer of weight to the outside of the roll, there wont be a roll. which equates.. no grip - no roll.


'In fact, too stiff an anti-roll bar can actually cause an inside wheel to lift completely off the ground during hard cornering. " this is because of too little suspension droop.. again this is not suspension travel. at this point, the outside wheel actually has the most grip...

the lateral torque of the whole car is exceeding the weight centre of the car itself.

 

[alantiong]

I have a scale model to actually explain this geometry if you guys wanna look at it over tt sometimes

 

[puterabrian]

Bro, recently I manage to change 19" rim + Eibach spring, overall performance is better than stock spring ( personal feel) do find a chance sharing the ride over tt section sometimes

 

[alantiong]

when you change to a 19" rims, you will definitely have more response to your steering wheel as you eliminate 1" of variable movement on the suspension.

The basic of suspension is to eliminate as much variable movement yet maintaining enough dampening to the chassis and structure.

most of us .. the daily driver needs some more than enough dampening!. some Gymkhana street racers car . . almost have only the tyres to dampens.. not necessary a daily driveable car.

i personally prefer fatter or higher profile tyres while matching it with better shocks. higher tyre pressures too. I am running 34-36 front, 37-38 rear and sometimes up to 40 depending on where i am going and how "rajin" am i that particular day to get down to pump it.

If i can i would run 235 45 17 front and 255 40 17 rear.. got more cushioning.. but dun look as slick as the 19"s.

if malaysian tyres are as afffordable as singapore.. i might go 19"s but for now.. i like it fat and sticky.. and no need to avoid potholes

 

[enghow200]

Dear Alantion, u see F1 don't roll into corner because they run full slicks. So much grip at the tires what they need is steering responce. F1 cars = Go kart cars are the same. When your tires have so much of grip. u can go all the way to the hardest settings. Its totally different into a street car. I can run harder i'm on Yokohama A050 semi slicks cause it give me the grip hence i can enter corner earlier and power early but I cant run the same settings on a Normal Goodyear or Continental cause i will understeer before i can enter power out.!!

Traction roll, Body roll firm vs hard is very subjective and depends on driver liking and their driving style. Too much body Roll car doesn't mean its a slow car. Firm and hard setting car doesn't mean its a fast car. Its overall that count. Fast into corner doesn't mean you can exit fast (sometimes can't exit too) .. Slow into corner u can power out earlier and exit faster.

Power without good control = Disaster. yes It's overall count....

 

[alantiong]

guys, this weekend my car will be at Bukit Jalil as demo for F30 suspension setup.

 

[Bruce_Z]

Hi F30 folks, Im letting go of my set of H&R sport springs since Im now on M Performance Susp. See the ad in the classified section or PM me if you are interested get this second hand set from me. URL: http://www.bmwclubmalaysia.com/foru...-H-amp-R-sport-springs-for-F30&referrerid=895

 

[alantiong]

good stuff!

Hi F30 folks, Im letting go of my set of H&R sport springs since Im now on M Performance Susp. See the ad in the classified section or PM me if you are interested get this second hand set from me. URL: http://www.bmwclubmalaysia.com/foru...-H-amp-R-sport-springs-for-F30&referrerid=895