I know this is not a new concept. I have already clarified the rules with ROAR where they only set maximum wheel dimensions, there are no minimums.
Current 2WD carpet tires are now based on a "Slim" design which shaves off a significant amount of weight (i.e. rotating mass).
So I decided to do a side by side comparison with a set of 4WD ProLine "Prisms" versus Raw Speed "Fast Forwards" on my 13.5 wheeler where anything you can do to reduce rotating mass is essential in being competitive for stock racing.
4WD Prisms weigh in at 216g
Fast Forwards weigh 153g
That's a total of 63g shaved of rotating mass!
Tire Diameter from left to right in following pic:
PL Prism (Rear) = 86mm
RS Fast Forward (Rear) = 82mm
PL Prism (Front) = 84mm
RS Fast Forward (Front) = 76mm
Average temps coming off track after 9 min with Prisms was 160°F
Average temps coming off track after 9 min with Fast Forwards is 120°F
Note that acceleration is notably more powerful and I had to adjust my ride height (and gearing) to account for the new diameter in wheel sizes. Grip was amazing with a very stable and easy to drive, the 2WD wheels are a pinch less "twitchy" than traditional 4WD wheels, but lap times are faster due to the improved acceleration. Most importantly, there is no detectable loss of punch toward the end of the run due to improved efficiency as well.
I made it a point to test 2WD wheels where Raw Speed tends to offer a little more lip in the hex than other brands of 2WD wheels where I have had issues with stripping out 2WD hexes on the wheels in the past which is why I stopped using them. On the current set of Raw Speed 2WD Slim wheels I have a combined total of 45 min of track time with plenty of wall taps and hitting pipe at full throttle as seen by the scuffs on the wheels in the photos to confirm no stripped hexes yet!
Current 2WD carpet tires are now based on a "Slim" design which shaves off a significant amount of weight (i.e. rotating mass).
So I decided to do a side by side comparison with a set of 4WD ProLine "Prisms" versus Raw Speed "Fast Forwards" on my 13.5 wheeler where anything you can do to reduce rotating mass is essential in being competitive for stock racing.
4WD Prisms weigh in at 216g
Fast Forwards weigh 153g
That's a total of 63g shaved of rotating mass!
Tire Diameter from left to right in following pic:
PL Prism (Rear) = 86mm
RS Fast Forward (Rear) = 82mm
PL Prism (Front) = 84mm
RS Fast Forward (Front) = 76mm
Average temps coming off track after 9 min with Prisms was 160°F
Average temps coming off track after 9 min with Fast Forwards is 120°F
Note that acceleration is notably more powerful and I had to adjust my ride height (and gearing) to account for the new diameter in wheel sizes. Grip was amazing with a very stable and easy to drive, the 2WD wheels are a pinch less "twitchy" than traditional 4WD wheels, but lap times are faster due to the improved acceleration. Most importantly, there is no detectable loss of punch toward the end of the run due to improved efficiency as well.
I made it a point to test 2WD wheels where Raw Speed tends to offer a little more lip in the hex than other brands of 2WD wheels where I have had issues with stripping out 2WD hexes on the wheels in the past which is why I stopped using them. On the current set of Raw Speed 2WD Slim wheels I have a combined total of 45 min of track time with plenty of wall taps and hitting pipe at full throttle as seen by the scuffs on the wheels in the photos to confirm no stripped hexes yet!
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