For what its worth, I've run those air filters on my blown small block street car (11.0@123). I also built a air filter base and top to run a 4"tall K&N. The triangle style with or w/o the foam and the K&N all run with in .05 of each other. Also for what it's worth my 1st pair of 10.5wx31M/T were 5 years old before I ever used them. 150 passes 60ft was still with in .05 best to worst at the end 2 years later.
Doug