Hey,Recently purchased a 2006 Audi A4 2.0T Q S-Line. Loving it so far but i can barley hear the blowoff valve if at all. So i am in the market for the loudest blowoff valve. I realize its a very tiny turbo but id still like to hear it and maybe even turn some heads. If anyone can help me out i would greatly appreciate it. Thank you
The reason for this is because the car has a stock diverter valve in the car. I would not even think about putting a blow off valve inside of this type of car. This is because the car will be running to rich off of the blow off valve. This can cause a malfunction in the computer system in your car. This also will cause a check engine light which will not be able to come off unless you take out the blow off valve and replace it with a diverter valve. A diverter valve takes the air in from the turbo then recycles the air back into the turbo to give it more power. The blow off valve gets the air from the turbo and pushes it out which is why you will get the swoosh noise. There is a type of valve that will allow you to pick what you want whether you want a swoosh noise or to keep the air. You can choose the percentage and I would put in 60% divert and 40% blow off if you really want the swoosh noise.
The 2.0t uses a recirculation valve that's incorporated to the turbo. Don't get a typical blow off valve as this will not work for your car. It is also solenoid operated so it wont be what most tuners are used to when it comes to blow off valve. You will get some extra sounds when under part throttle but this is due to the way Audi designed their car. This helps eliminate turbo lag by already having some pressure in the intake track even when not needed. By venting this to the atmosphere (BOV instead of recirc valve), you may reduce the engines ability to produce boost from part throttle to full throttle. This will cause an increase in turbo lag. This isn't all that noticeable though. As far as the loudest, they're all gonna be about the same. There is only so much that can be done on an internally regulated recirc valve to make it a real blow off valve. Most are going to be a spacer plate that has holes in it to allow for pressure loss to the atmosphere when activated. There are some companies that have relocation kits that allow the use of a typical mechanical type blow off valve. ATP turbo has one for the A3 but I don't think they have one for the A4 yet. Do some research before you buy and if possible, try to get a sound byte on the net to see if its exactly what you're looking for.
first off dude, it comes stock with a diverter valve. ive been doing research and so far the best thing ive found to get it loud is to upgrade the diverter valve and get a spacer (all forge) if you dont wanna spend that much then idk what to tell you. chipping your car improves boost so that would help too, also a cold air intake could improve it. all together and youll turn some heads. i have the same car just not s-line mines quartz grey :) good luck bro rick from philly
