i looked for a sticker and no dice.... there isnt one there. I did alot of looking and i think i probably have the 2.73 gears.
Would a tune be premature at this point? Like a canned tune from Diablosport or somthing?

 

Try this. Assuming you have the stock tire diameter. With the a4 in drive or 4th gear overdrive and you are traveling at 70 mph your engine rpm will be,

2:73 = 1675

3:15 = 1950

3:42 = 2100

3:73 = 2300

3:90 = 2400

4:10 = 2525

My 04 coupe has an automatic with the 3:15 differential. I have a Z06 muffler, x-pipe and a Vararam intake. The x-pipe is there because I put a B.B. PRT exhaust on it and the drone was over the top. I added the x-pipe in an attempt to mellow things out and it helped but not enough so I put the Z06 ti muffler on it and left the x-pipe. The x-pipe and the Vararam really don't add much in my opinion and I consider my car to be stock. The biggest difference came from having my car tuned. I use a Diablosport inTune and had my car tuned on a dyno by a tuner that tunes with CMR program. The tune is stored in the tuner and I can put it back to stock and put the stock air filter back on when smog test time comes around. The transmission tune and torque management make the car so much more fun to drive and the engine is obviously making more power. I have had my car on the drag strip 2 times since having it tuned. Every pass has been under 13 seconds with a best of 12:87 @ 111 mph. on street tires. Any 12 second car on the road feels pretty strong to the average driver.

If you have the 2:73 rear axle ratio any other mods like an air intake or exhaust will be barely noticeable. They will make noise but your car probably won't be much quicker. Even a tune for that matter. Get the gears first. You can find good 3:42 differentials in the for sale section. The gears will make a dramatic difference. Way more than any muffler or air filter. Then go for the tune. If it isn't enough, then start looking into adding power and be careful there because in my opinion air intakes and mufflers are expensive and really don't do much for power. Long tube headers are good if you can go with no cats or even high flow cats but I think you are in California and those will not work out well for you unless you don't mind taking them off every two years.

I like the inTune and yes, it could be a starting point. You can get a good tune from this guy, Lewis Eaton, diablo.help@gmail.com for a about $135. Again the biggest gain will come from the changes he can make to the torque management and transmission tuning.

I just wanted to say that I do not work for Diablosport but I have had great results using their products. Lew is a good tuner and a good guy to work with.