I have a 2001 A4 1.8t. I was just wondering what direction I should go with, when I get a new exhaust. I have the ECU upgrade from APR and I'm planning on getting the KO4 turbo upgrade. And what do I have to worry about when getting the KO4, if anything?

Any help is appreciated, thanks

 

You probably should look into a bigger intercooler with the bigger turbo. And as far as the exhaust, leave the cat on, remove the factory mufflers and either run a straight exhaust with a couple of glass packs or put a high flow muffler on in place of the rear muffler if you want it to be a little more quiet. There are plenty of cat back exhausts and exhaust mani's, new cats and stainless steel pipes you can buy, but for the money I'd just remove the factory mufflers and get a high flow for the back.

 

Probaly would want to upgrade your bypass/diverter valve.

 

new beefier clutch would be a good idea as well. you don't want to put big turbos and not be able to drive your car cuz you fried the clutch.

 

get a new downpipe (leave the cat on since i have to breath the air) but then just put a glasspack on. thats what i have on my T3 equipped 1.8t. also the whitsle form the turbo is ULTRA LOUD AT IDLE when using the glass pack. mine exits right in front of the driver side rear tire. just like Pobst

 

breathing is overated but some states carry severe fines if your caught without your cat I was told by a mechanic in mass that its a $10,000 fine or some crazy **** like that... but Id check your local laws

 

Welcome to the forum jamie1256 !

Your upgrade will require an upgraded DV, exhaust system, and intake. Many of the kits include somne of what is required, but not everything. Upgrading the clutch and brakes are a subjective issue. If you want to drive the car extra hard from that point forward, then it may be wise to upgrade those components, too. It would be very wise to get a boost gauge as well.