PRODUCT BULLETIN: Next Gen RCES is Slated for 2027

Lakeville, Indiana (November 12, 2026) - After collecting valuable data and feedback from the racing community on the RCES spec tires, Hoosier is proud to announce a few refinements to this product line that are intended to further optimize balance and longevity within respective NASA spec classes.

Beginning January 1st, 2027, Hoosier will be launching a new Spec E46 tire, and a new 17” & 18” tire for American Iron (AI), Spec Iron (SI), and Camaro Mustang Challenge (CMC) NASA classes.

The new Spec E46 tire will be a “P235/45ZR17 RCES” size and benefits from a taller diameter (approximately 1”) to keep cars off the rev limiter at longer tracks, such as VIR. The construction of the tire is the same as the previous P245/40ZR17 RCES. The compound has been slightly enhanced to produce even more consistency and increased longevity when compared to the current Spec E46 tire. The spec table below compares the dimensional differences between the previous P245/40ZR17 and new P235/45ZR17.


The AI, SI, and CMC classes will have the option of fitting a newly constructed P275/35ZR18 or P275/40ZR17 RCES on their cars in 2027. This advanced casing is designed to provide more sidewall compliance and lateral grip at higher air pressures through footprint optimization. The benefit of using higher pressure is that it increases stability in the tire and allows drivers to use more of the tire’s contact patch on the rear axle, which is camber limited. Hoosier has also taken this opportunity to wrap the new casing with a more heat tolerant compound that elevates the consistency in performance throughout a race stint. Both compound and construction changes are intended to improve wear resistance, increase the number of usable heat cycles, and widen the working window of the tire.

The physical dimensions of the new P275/35R18 RCES and P275/40ZR18 RCES will remain the same as their predecessors.

The new line of RCES tires for NASA Spec E46, AI, SI, and CMC classes will bear the “H” DNA logo on the tread, signifying the latest generation in spec tire performance.

Due to the changes in both construction and compound, the new P275/35ZR18 RCES and P275/40ZR17 RCES should not be mixed with their predecessor tires on the same vehicle. Competitors should run a complete set of either the new-generation or previous-generation tires.

For more information or to place an order, please visit www.hoosiertire.com for a complete list of distributors.