I have a 99 2.8 b5 a4. Any recommendations on ways to increase its acceleration, handling and overall performance (other than turbos and supers)? I know there are a lot of options when it comes to small performance upgrades but I'm not sure what's worth doing and what I shouldn't bother with

 

Not a whole lot you can do for that car in an N/A setup. Intake and exhaust for the most part. I don't know if a cat delete/straight pipe setup would be worth the time and money, but I know a tune is only going to give you about 15 more HP.

G/L

 

Would getting coilovers, better wheels and tires, upgrading the mounts, getting a performance camshaft and high flow cats change much overall?

 

Personally, I don't think coilovers are necessary, unless you're either racing your car, or making it a show car. If you did a cat delete, cams and a tune, you could probably get some decent power. That's probably the best thing to do (that I can think of). I bet you could get some nice numbers with that combo.

Better wheels and tires will look good and give you better handling & traction, but more rolling resistance (which won't really effect anything at this level).