I'm looking to do the intake, headers, and cat back exhaust. Most people here with those mods are putting out numbers close to 500hp.
here is an isf with intake, headers and exhaust. 416whp= 492hp
hope that helps you decide to keep your car.
the new m3 is only a 4.0 liter engine. its already putting out 100hp per liter. you dont have to much more room to play with that car and make it more powerful.
the isf is 5.0 liter. therefore it has more potential than the m3 if your looking to fix it up. bigger motor= more potential power