I am thinking of taking the high flow cats off and retune the car on the dyno.The car has kook headers and nitrous.so what i want to do is only use 110 octane and advance the timing as much as i can without using NOS.The car put down 445hp to the wheels and 392tq to the wheels.My question is would there be a big gain on doing this.Car runs 11.80@118 and 11.0@128mph with nos.I just need your 2 cents guys. Thanks. how much HP and TQ would I make

 

I wouldn't expect too much. From everything I've ever read on the subject high flow cats don't really restrict that much (I would guess <5 HP). The main reason why people go ORY is because they don't want to pay the price for the cats when they don't really add to anything power wise

 

i gained about 7/7 after a tune which isnt anywhere near stock and not stock cubes.