Have question for Magnaflow owners

[awbrown]

I have flow masters on my 97 silverado with a stock 454 and they exit behind the rear wheels both on the pass. side.. you do get a lot of drone in the cab even at highway speeds... Afriend of mine and I tested 3 brands of muffler on the dyno in 2003 on a 470 inch BBC .. We had flowmasters ,spintech,magnaflows and borla .. the straight thrus were within 1 hp of each other .. the flowmaster was down a couple more , but the spintechs were down by 15+hp ,but they were the quietest ones also ...