im still fairly a new-b when it comes to mods. My next mod will probably be cat back exhaust(injen) most likely. After that im not sure. I know about plenum and headers but what about the following: what does a 3.9 final drive thingy do? and how bad is this for a car, and how expensive, same goes for pulleys, what does changing the clutch do? are test pipes illegal in ny( i thinky they are) and if so will they make me fail an inspection? Thanks for the help guys, and no flaming! everyone was a new-b once

 

I'm not too knowledgable about thefinal drive. the pulley's are usually lighter so they will spin easier/faster. A clutch is usually only needed if you drive your car very hard, lots of burn outs or if you have FI and need something that will hold more torque. Test pipes will not pass a visual inspection. You might be able to get away with high flow cats. If you know someone that does inspections though, it becomes very easy to pass lol. Those are my thoughts

 

Check out 350evo.com for info and pricing on the final drive. As far as bad for the car, prob. bad on gas mileage, but not a big deal besides. IIRC, the 3.9 comes as standard equipment on the 5AT cars. Can't speak to legality of test pipes in NY, but I would think if you kept your stock cats around and swapped before inspection, you should be fine.

 

The AT5 DOES NOT come with a 3.9 final drive . It comes with a 3.30 [ or close ] The MT6 comes with a 3.5 final drive . The 3.9 is good for coming out of corners and for off the line . It will keep rpms higher and great worse gas MPG

 

I stand corrected! Sorry for the mis-information...