older article but some good information...enjoy!
A quick synopsis is below:
Regular High Rigidity Enkei GTC-01 18×10 +22: 23.76 lbs.
Specially Lightened Version Enkei GTC-01 18×10 +22: 19.8 lbs.
The weight of the lightened version was reduced by 3.96 lbs. Both used Advan A048 (265/35-18 M-Compound). Testing was performed at Ebisu East Circuit using MCR’s Z33 driven by Kobayashi and under the same specs (ie., tire pressure, # of laps, etc.)
Regular High Rigidity GTC-01
Best Lap: 1 min. 4.646 seconds
Top Speed: 147.16 km/h @ 17.83 seconds
Specially Lightened GTC-01
Best Lap: 1 min. 5.045 seconds
Top Speed: 141.46 km/h @ 17.74 seconds
A very rough and quick recap: The surface temperature of the tires for the less rigid, specially lightened GTC-01 were higher overall with extensive wear on the outer portion while not enough contact/usage on the inner portion. The high rigidity regular version GTC-01 showed even usage throughout the inner and outer parts of the tire. Also, the low rigidity, lightweight version wheels gave/bent when taking aggressive high speed turns even affecting the height of the car which even led to scraping and alignment problems. Furthermore, the lighter version accelerated much quicker, but ultimately did not lead to faster times. In summary, Kobayashi expressed that a balanced wheel with both rigidity and lightweight characteristics is important, but he never imagined that the effects of rigidity played such a large role.
