Tech Bulletin G60 Tire Bristol Dirt Nationals 3/4

On February 24-25, 2021 testing was conducted at Bristol Motor Speedway in preparation for the Karl Kustoms Bristol Dirt Nationals March 15-20, 2021. A number of items were looked at including safety, tires, gears, and track prep.

Due to concerns of potential competitive advantages between the IMCA Stamped G60 and Unstamped G60 Hoosier Tire, testing was conducted with both compounds. The conclusion was that the Unstamped G60 had a .7 to 1 second competitive advantage at Bristol Motor Speedway. It was determined that asking a potential 500+ racers to purchase would be detrimental to the event and participants. In addition, supply is not available of the Unstamped G60 in those quantities.

From Hoosier Tire:

“Find below the lap times and comments from the G60 comparison evaluation we did at the Bristol test day on Feb. 24th. I feel this was a fair comparison test as we mounted new sets of both stamped and non-stamped G60’s, left them both unaltered, ran them back to back on the same car, and used the closest tire settings as possible. Kyle Brown drove Mike Van Genderen’s IMCA Modified for this test.

IMCA G60

20.99, 20.21, 20.28, 20.33, 20.21 – average 20.404

Comments – consistent, on the chip at the start/finish line, RF didn’t steer in well but recovered well on exit

Non-plated G60

20.59, 19.93, 19.92, 19.66, 19.57 – average 19.934

Comments – better traction, did not hit the chip, RF can steer through any tightness, could run 50 laps with that set of tires.

In addition to the performance discrepancy, inventory availability of the non-stamped G60 tire for such a large event could have been a concern. In order to assure everyone has the same opportunity to buy tires as their fellow competitor, utilizing only the IMCA stamped G60 is the best solution.”

The Modified, Sport Mod, and Stock Car divisions will compete with the traditional IMCA Hoosier G60, siping allowed, similar to an IMCA sanctioned event (Note: BDN is not sanctioned).

The Unstamped G60 will not be utilized for this event in any division.

Hoosier Tire South will have tires available at the event.

**SWIPE TO SCROLL ON MOBILE**

ClassSanction RulesetTires AllowedGrooving and SipingPosition
604 Crate Late ModelFASTRAKHoosier FT 200 or FT 400NONE FOR THIS EVENTAll 4 corners
604 Crate Late ModelCrate Racin' USAHoosier Crate D21 or Crate D55 or Spec/HTS 1350 or Spec/HTS 1600 - no steer tiresNONE FOR THIS EVENTAll 4 corners
604 Crate Late ModelAmerican Crate All Star Series Hoosier Crate D21 or Crate D55 or Spec/HTS 1350 or Spec/HTS 1600 - no steer tiresNONE FOR THIS EVENTAll 4 corners
602 Crate Late Model602 BanditsHoosier Crate D21 or Crate D55 or Spec/HTS 1350 or Spec/HTS 1600 - no steer tiresNONE FOR THIS EVENTAll 4 corners
602 Crate Late Model602 AllstarsHoosier Crate D21 or Crate D55 or Spec/HTS 1350 or Spec/HTS 1600 - no steer tiresNONE FOR THIS EVENTAll 4 corners
602 Crate Late ModelCrate Racin' USAHoosier Crate D21 or Crate D55 or Spec/HTS 1350 or Spec/HTS 1600 - no steer tiresNONE FOR THIS EVENTAll 4 corners
Super Late ModelsALLHoosier 1350/21 or 1600/55 or American Racer SD48 or MD56Any allowedAll 4 corners
HornetsSCDRADOT Street Legal Tires ONLYAllowedAll 4 corners
HornetsIMCADOT Street Legal Tires ONLYAllowedAll 4 corners
Open ModifiedsUMPHoosier M30 or M60Siping onlyM60 RR only
Open ModifiedsUSRA/USMTSHoosier M30 or M60Siping onlyM60 RR only
Open ModifiedsWissotaHoosier M30 or M60Siping onlyM60 RR only
Open ModifiedsIMCAHoosier M30 or M60Siping onlyM60 RR only
Stock CarsIMCA Stock CarsIMCA STAMPED Hoosier G60Straight siping onlyAll 4 corners
Stock CarsUSRA Stock CarsIMCA STAMPED Hoosier G60Straight siping onlyAll 4 corners
ModifiedsIMCA ModifiedIMCA STAMPED Hoosier G60Straight siping onlyAll 4 corners
Sport ModsIMCA Northern Sport ModsIMCA STAMPED Hoosier G60Straight siping onlyAll 4 corners
Sport Mods602 ModifiedsIMCA STAMPED Hoosier G60Straight siping onlyAll 4 corners