hi guy's .
i did couple of mods in my car with turbotrix. i want to install crank pulley from perrin to gain hp little bit more ...Now they told me i should change my high- flow cat to test pipe, because my ecu don't like the cat ,also when it is warming up i actually loosing some hp.what you guys think about it? how much hp can i have with this changes ? it is worth to put the test pipe on it? it is too loud?
thank you!
