Cateva informatii despre cum afecteaza distantierele stabilitatea si comportamentul masinii:
Changing wheel offsets will change the Scrub radius. The scrub radius is the distance between where the tyre centre line (vertical...from front view of car) meets the ground.......and the king pin inclination or steering axis inclination line meets the ground.
If the KPI line hits the ground inside the tyre centre line, that is negative scrub radius.
If the KPI hits the ground outside the tyre centre line, this is positive scrub radius.
Negative scrub radius is usually found on FWD cars......and the amount effects the steering weight. The more negative scrub radius there is.....the heavier the steering. This would be the same if wheels with no offset was fitted.
But if there is too much negative scrub radius on FWD cars.....torque steer and bump steer become apparent. This again would happen if wheels with less offset than standard are fitted.
Negative scrub radius is good on FWD cars with split diagonal braking systems. If one side is to fail.....thus leaving only one front brake and the opposite rear brake then under braking, the steering is stable.
If positive scrub radius was used in the above situation......the steering would pull sharply in the direction of the braking front wheel.
Si despre cum afecteaza dimensiunile jantelor si indirect a anvelopelor stabilitatea masinii:
For a 6J rim......to keep the sidewalls a bit tighter.....so quicker responding, a 175 tyre would be an advantage......though 185 is OK but will be SLIGHTLY less responsive.
On the 106Rallye S2 a 6J rim was used and Peugeot fitted a 175/60 tyre.
For a 195 tyre a 6.5J used to be the best for steering response. And depending on the width of the particular 195 tyre it may still be. But all tyres seem to be getting wider than their marked size would suggest.
Again a 7J rim for a 205 tyre.
Remember a tyre with better spread sidewalls will have better steering responce. But will also break away quicker and sharper on the limit of adhesion.
This is why most vehicle manafacturers will use slightly narrower rims for a given tyre size......than what is actually ideal...depending on what they are trying to achieve.
Quite often, a 6J rim will be used for a 195 tyre and a 205 on a 6.5J rim. This would slow the steering responce....but also make the car less agressive on the limit.
Also it will be an advantage to try and find out information on a particular type of tyre as they will all have different strengths of sidewall.
The Toyo Proxes tyres have strong sidewalls where as the Goodyear Eagle F1 GSD2 had a soft sidewall......so the width of tyre/rim can be altered accordingly.
Imi cer scuze fata de cei care nu vorbesc engleza.
Puteti citi aici un articol foarte bun despre suspensiile la autoturisme scris de un inginer care proiecteaza asa ceva:
http://forum.205gtidrivers.com/index.ph ... opic=13120Cu alte cuvinte m-as gandi de doua ori inainte sa pun distantiere la roti sau sa pun body-kit custom. Am un prieten aici in Cluj care face asa ceva si mai stiu pe cineva in Brasov care face chestii custom, dar toti care si-au pus body-kit-uri custom pe masina le-au dat jos si au readus masina la stock dupa cateva luni. Fie le spargeau tot la o saptamana din cauza gropilor sau a bordurilor, fie crapa fibra la imbinarea cu plasticurile sau tabla.
Bafta