Metz also explained that a decade ago there weren’t chassis certifications, just a basic guideline of 9.99 type cage. As the cars got quicker and heavier, SFI mandated 25.5, 25.2, 25.1 and now 25.3. The SFI Foundation’s Jennifer Faye was another insider we contacted on the subject, “The need for such a spec did not present itself until a few years ago. Until then, the existing specs were sufficient. As technology of the equipment advanced, along with the talent of the builders, tuners, and racers, it rapidly became apparent that the heavier door cars would eventually break through the existing specs.” It wasn’t until such sanctions as the NMCA, NMRA, PSCA, and ADRL petitioned for SFI to start developing something that will allow these heavy cars to run at their full potential, while remaining within SFI’s specs.
Who Made 25.3 Possible?
Some of the country’s top chassis builders teamed up to develop this new certification, Richard Earle of Suncoast Racecars is the chairman of the committee. “While he may not be a primary builder of these cars, he was selected as chair due to his experience with the SFI process,” Faye explained. Other builders included Dan Neumann of Dan Neumann Race Cars, Chris Lundsford of Sheppard Race Cars, Mark Wilkinson of Racecraft Inc., Bryan Metz of Metz Performance, Gary Rohe of Gary Rohe Racecars, and Larry Larson of Larson Race Cars. SFI also appreciated the invaluable input from Trey Capps of ProMedia, Jim Collins of NHRA, and Roger Goode, who is SFI’s Professional Engineer.
Although we spoke with Bryan Metz of Metz Performance for this article, other chassis builders that helped develop 25.3 include the Chairman, Suncoast Racecar’s Richard Earle, Dan Neumann of Dan Neumann Race Cars, Chris Lundsford of Sheppard Race Cars, Mark Wilkinson of Racecraft Inc, Gary Rohe, and Larry Larson of Larson Race Cars. SFI also appreciated the invaluable input from Trey Capps of ProMedia, Jim Collins of NHRA, and Roger Goode who is SFI’s Professional Engineer.
This 25.3 chassis spec is intended to for OEM frame or OEM-modified frame door cars that are faster than what a 25.5 covers, but heavier than a 25.2. The sanctioning bodies, along with SFI quickly recognized the need for this separate spec. “What’s interesting, though,” Faye said, “Is that at the same time sanctioning bodies were requesting a new spec that would eventually become 25.3, car builders who were already familiar with working in SFI chassis specs were also calling SFI expressing their need to fill the gap between 25.2 and 25.5. They were looking for guidance in how to build these faster, heavy door cars with appropriate safety in mind.” According to Faye, other sanctioning bodies recently joined SFI such as PSCA, who were not members at the start of the 25.3 project, but are indicating that they are interested in using the spec as well.
What’s the difference from 25.3 to 25.2/25.5?
So the big question on everyone’s mind is, what are some major things that are different on a 25.3 spec compared to a 25.2 and 25.5 in terms of added bars? Faye elaborated, “Historically, when SFI chassis committees work on developing a roll cage spec for a performance range that grows out of existing specs, they keep in consideration that there may be cars in the field that need to be upgraded to the new spec. With that in mind, the spec is developed to meet the necessary safety parameters, but so that some existing cars can be updated to meet the new requirements. While not all cars can always be updated, some can.” She went on, “There is also standard precedent that must be followed for any chassis spec, whether it’s for a door car, dragster or funny car. For example, any chassis faster than 7.50 must be constructed of all round chrome moly tube.
In taking on the task of developing Spec 25.3, the committee used 25.2 as the basis and included construction requirements from 25.5 that pertain to OEM frame or modified frame cars such as the rear frame rails and rear braces, as examples. In Spec 25.3, you might see a little more detail in specific construction requirements than in other specs because in addition to the safety objectives, the committee took the perspective of providing builders with a more detailed guideline to building the chassis.” According to SFI you will see the major differences between a 25.3 and a 25.5 roll cage will be in the roof, door, and floor bars. Either additional bars or larger bars (or both) will be required. In some cases, there are options available to keep existing bars while adding support tube members to meet the new spec. These are only generalities, so a builder will definitely want to obtain a copy of the actual specification from SFI in order to have the
detailed requirements.”
A Chassis Builder’s Take on the Change
We asked Metz if he felt this upgrade is good for the sport, or just another thing to deplete a racer’s pockets. “For us at Metz Performance, we expect to see a lot of upgrades to this spec, I’m sure.” I think it’s good because now there’s a safe spec to allow anything quicker than 7.50 to run at 3,600-pounds. It really gives some racers a larger window there are a lot of cars out there that are chrome mol, but weigh too much. This will salvage this situation. We have three or four customers that weight a couple hundred pounds more than their cert will allow, now they have the option of getting those heavier car back on the racetrack and it’s a minimum upgrade.”