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Falken RT660 Info Needed


TMO Intermediate
The 660 was bench marked to perform at the RE71 level and wear better. It really is up to what you want out of a tire.

Just getting started and care more about turning laps than being fast and street drive alot: Hankook, Nitto

Intermediate who wants to set the fast time with your buddies but will sacrifice wear in HPDE: RT660, RE71R, Rival S

Chasing a lap time instead with a large tire budget for the year: Yokohama
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TMO Race
Tire Rack has the 315/30-18’s listed now, ETA Oct 16th. Big price difference between this and what America’s Tire (Discount Tire) has them listed for on their site ($293). My guess is that America’s Tire is an error?


Bill Pemberton

0ld Ford Automotive Racing Terror
Blair, Nebraska
W2W Racing
20+ Years
Call TireRack and plug in Ext. #4362 ( Luke Pavlik ) as he has been there well over 20 years. Find out about the price difference and if there is an error? Have seen advanced pricing wrong over the years , but sure does not hurt to verify .


Cones - not just for ice cream
20+ Years
275/35-18 RT660 next to a 295/40-18 RT615K+ both unmounted.
On section width, they're about the same. But if you look at the tread surface, the RT660 (on the right) is much more rounded overall and falls away at the shoulder; while the RT615K is flatter across with a more square shoulder. So some of that apparent width is lost at the contact patch, unless it has a much stiffer sidewall and you can run a lower pressure to get the carcass to deform flat across.

To me, the RT660 looks to be designed to work better on camber-challenged cars. Instead of rolling onto the edge of the square shoulder of the RT615K and wearing down a narrow stripe, you'll roll onto the curved outer portion of the RT660 and have more total contact patch and support. But I'm not a tire engineer.

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