I just bought an 03 A4 3.0L I was wondering what I should do first.
Whatsthebest way to increase thecars performance without spending tons of money?

 

Not much for 3.0/NA engines
Exhaust would be your best bang for the buck. Check out our forum sponsors on the right or the audi links link for places to buy from. Or go custom.
You could always supercharge it, thats not cheap at all though, but very cost effective and great bang for the buck.
and always use this for the basics: https://www.audiforums.com/search.asp

 

Exhaust would be good, and someting else small could be a drop in K&N filter, or you can buy a cold air, fairly low cost.

 

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