The SFI Spec 25.5 has been revised, effective May 12, 2015. The newly revised version is designated as SFI Spec 25.5C and is for Full Bodied Car Stock or Modified/OEM Floorpan and Firewall with OEM Frame or Uni-Body Construction – 7.50 to 8.49 Seconds; 3,600 lbs. Maximum.
This revision clarifies the use of OEM rear frame rails in Unibody cars under certain conditions. To download a PDF copy of a summary of the revision, click here: SFI 25.5C Revision Notice 05-12-15. Previous Chassis Spec Revision Notices may also be found on our Tech Advisories page.