k i have a remus catback for my 2.8 coming prob within the next week. SO i just jacked up my car just to see what i was dealing with...and i dont understand. Can i do this myself? The piping is welded to the big cat, i thought i could just bolt this thing on, am i wrong?

can anyone gimme some insight while i still have my car jacked up?

What I would do is take your car (and cat back) to a shop, have them cut all that **** out from underneath your car and put in high flow cats. I think you might want the backpressure since 2.8's aren't turbo, otherwise you could just cut the cats out, and have them weld on the catback. There is welding involved so unless you have a TIG welder, you're kinda screwed. I was under the impression for a while that cat backs were "bolt on" because some exhaust systems have flanges that you can just unbolt and voila, bolt the new goods right up, but it's more like "weld on".

I would highly reccomend welding.. even if it was possible to bolt on.. just find a good muffler shop.. they wont charge you to much

****, and i dont have a new cat coming, i was talking about the stock ones. Damn it..i thought i could do this myself. Are Highflow cats CARB legal or whatever?

Yeah, highflow cats are carb legal I believe. You could just leave the stock cats on there, but there's going to be more restriction vs. a highflow cat. It will definately work and you probably won't have any problems, but I was just thinking while the car was on the lift have them replace them with something a little more HP worthy.

so where am i gonna find a highflow cat for the 2.8? I cant seem to find one..

A muffler shop should have them in stock, basically they just need to fit the inlet/outlet pipe and of course the overall size should be about the same so when you're car is dropped it won't drag on speed bumps.

k last question...how much is a highflow cat gonna run me, ballpark it.

Damn, I know for my 2000 GMC Sierra a high flow cat was like $120, but that thing was HUGE so for an A4 maybe $80-$100? The high flow cat is the way to go if you're going exhaust, you can def. get away without but it makes your exhaust sound a touch better plus a little less restriction = go faster haha. My truck had dual flow masters and high flow cats, it was loud as ****. Damn I miss that truck sometimes.