Those of you who have had the chance to drive the M5 on the Nürburgring Nordschleife, have probably noticed that it understeers terribly resulting and poor laptimes, awkward balance and excessive wear on the outside of the front tyre.
The other was I was advised to use 3 bars in the front and 3 - 3,3 bars rear - I tried with 3 front and rear, the results were mindblowing.
It feels like a different car, the understeer is almost gone, it only really understeers when it has to, there's no wear on the outside of the tyre and when it understeers you can feel what is going on. The rear of the car is way more stable then before, at highspeed or over crests it would become unsettled. Just by upping the tyres pressure I felt more comfortable driving the car at higher speeds and cornered way better, it all resulted in be able to shave off 15 seconds on a lap, BTG 8:35 mins (previous 8:50).
If you take your car on track, especially if it resembles the Nordschleife a little, you should try upping the tyre pressure, it makes a world of difference.
I'm now interested in knowing if it's actually safe to run high pressure in the front tyres, the rear should be fine. It's only slightly more than what's recommended anyway.
Don't know what 3 bars is in PSI, silly measurement anyway
I assume the Ring M5 has OEM Dunlops or Pilot Sports? Jeff
__________________
2003 M5 LeMans Blue/Caramel/Walnut
Dinan S3 Includes all Dinan S3 Mods With JRZ Sruts/Shocks, Oil Cooler, Monoball Links
StopTech 4 Wheel BBK With Red Calipers And Slotted Rotors
Axxis Ultimate Pads
M Enhanced Audio
Park Distance Sensors
Two Sets Of Dinan Lightweight Forged Wheels
Winter Tires - Michelin Pilot Sport A/S - 275/35ZR18(Y) (F); 285/35ZR18(Y) (R) (Not Sure If They'll Survive The S3)
Summer Tires - Toyo RA1s- 275/35ZR18(Y) (F); 275/35ZR18(Y) (R)
Dual, Front Mounted LE30's With Custom AIDesigns Kill Switch/LED Panel
Valentine V1 With Stealth One
UUC Short Shifter With DSSR
Oil - BMW/Castrol 5W30 Changed and tested every 3000 miles.
After a little bit of experimenting i use 3,0 bar front and 3,2 bar rear.
In stead of air i use N2, it has less presure raising at high temperatures.
I tried the standard Dunlops, the Michelin PS2 and the Toyo Proxes T1-S.
Dunlops were too soft in de side wall.
Michelin PS2 have superb grip but are a bit unstable on the straight.
Toyo's feel fine but have much less grip and are fun for going side ways :-)
After a little bit of experimenting i use 3,0 bar front and 3,2 bar rear.
In stead of air i use N2, it has less presure raising at high temperatures.
I tried the standard Dunlops, the Michelin PS2 and the Toyo Proxes T1-S.
Dunlops were too soft in de side wall.
Michelin PS2 have superb grip but are a bit unstable on the straight.
Toyo's feel fine but have much less grip and are fun for going side ways :-)
I'm planning on trying it out with N2, I just need to find out if I can run the tyres at 3 bars constantly, off the track that is .. if not, then it'll be a pain in the hole having to swap air/N2 every few weekends.
For street usage i have the same demands as for track usage, i like to have sharp steering, good grip, not too mucht outside wear on the front tires etc.
I used to have air in my track E30 325i tires, cold they were 1,6 bar, on track temperature they were 2,1 bar, the desired pressure for the type of tire i use.
With N2 the difference is not that big.
Interesting that the door jam on my M5 says 44f/48r. If I did it correctly, 3.2=~46.2psi.... after much street experimentation, I run 42/44. I will up the pressure's in accordance with these findings and see what happens.
Thanks for the info.
__________________
All the best,
Jerry 00 Z8 Jet Black/Red Sport / some others
Last edited by MEnthusiast; 25th May 2004 at 13:54.
Linear Mode
