EFI Performance LLC is a late-model GM, Ford, and Chrysler dyno tuning and performance automotive specialty shop.

February, 2017 - We have added a line of pigtails and adapter harnesses to products; check them out!

May, 2016 - Mail Order Tuning has been moved over here from TunedbyFrost.com but can be purchased through either site. We hope to have our product listing updated within the next few weeks. Thanks for reading.

LS1 3 wire MAF to Delphi 5 wire MAF Harness WITHOUT IAT plug LS1 3 wire MAF to LS3/LS7 5 wire MAF Harness with IAT plug GenIII 12200411 "411" 512K Bead Blasted Certified PCMs