I have a 06 5AT coupe pretty much stock except for a 5/16 motordyne spacer, and ztube, I have about $1600 to spend and I really cant decide what to buy.

Its between the transgo **** kit, motordyne tdx v2 exhuast, or just the art pipes, I have thought about coilovers but my driveway is steep and at stock height it scraps the bumper. Any help or other mods please help me decide.

I'd get the TDX, transgo kit would be awesome but probably also voids any warranty you may have on your transmission.

coilovers, get boards for your driveway.

The Motordyne spacer is a great mod and his exhaust will be a great addition and sound way cool. Then you can decide if you want to keep it legal by going with his ART Pipes or opting for HFCs for the best sound on the planet....Gary

+1 for the HFC!!! You would also feel the gain right away.

ART pipes or HFC and tune. It'll feel like a brand new car

Good luck with your modding, I have a 06 5AT as well lol but I would deffinetly get an exhaust system and like they said HFC or Test pipes if you don't mind the sound. I am going to get a X pipe for my X02 HKS replica soon if you ever wanted a deeper tone I would go with a x pipe.
Make sure to post some pics for us

new tires, new brake pads, and some track time.

Cars come and go, but driving skills / car control stay with you.

I read that most of the restrictions are in the stock cats so really thinking about purchasing art pipes and some other goodys.

Well if you get the hfc/tp and a full exhaust you would love your car all over again.

All these are great mods so it's really what you're looking for. My friend just had the transgo kit installed and it was an amazing upgrade for the automatic. But the exhaust puts a smile on your face every time you start the car.

Perfect response....^....get the Motordyne exhaust, you'll thank us when you do! The OE cats do have a lot of restriction but installing ART pipes will make your coupe illegal and you won't like the major stinky exhaust. HFCs will make your exhaust sound incredible and give you another 8 RWHP....Gary

@ alxn91 - I also have a '06 G35 AT. Mods are currently - MD 5/16 Spacer, ART Pipes, SxExCx grounding kit & shift ****, TransGO kit, XYZ Y-pipe, b2autodesigns 25mm spacers, CF z-tube, and pop charger - I just recently installed my XYZ and well i love how hard my G pulls right now.. Lol.

So in my opinion, you could spend all $1600 on exhaust.. but you could do the TransGO kit (about $600 part/install), ART pipes ($500~), and some other goodies..

Of course, you can take all the recommendations with a grain of salt.. And getting a tune wouldn't be necessary until after complete bolt-ons, just wouldn't be cost effective. Well good luck modding bro!!

I'd personally try and make coilovers work for your car, even if you lower it just a little bit.

HFC/Exhaust gets my vote

I fell in love with my car all over again when i put my EVOTT on ....and then again when i put my Berk HFC's on...and then again when i got my osiris tune