Hey all,

I bought a 2008 Infiniti G35 from a friend. It has the 3.5L 35HR motor, Berk High-Flow Cats, aftermarket dual exhaust (I believe also Berk) and some sort of large bore mufflers. When I first got the car it ran incredibly well, over the next few months I experienced minimized power and throttle response. I don't know the age of the plugs/coils and fuel injectors, but would this be the first stop on the replacement list? Also any decent tunes I could add to improve engine performance without causing damage?

Thank you for any and all replies!

Best regards,
Poe