

Up to 320 PS (235 kW) with your A4 in 3 tuning stages
Here you’ll find everything you need to exploit your Audi A4’s full potential. Our tuning guide for 1.8T engines with code BEX is divided into three clearly explained tuning stages, which tell you all the necessary parts and most important tips. This is the way to a safe and long-lasting boost in performance.
Engine Code:
BEX
Installed in:
Audi A4
Year of manufacture:
2002 – 2004
You need this extra to make it last:
Chip tuning is a lot of fun and you don't necessarily need any additional components. However, you shouldn't use longlife oil, but rather Castrol Edge 10W-60 oil.
BAR-TEK® tips
As always at this point we recommend 102 octane as fuel. This makes the engine knock less and gives you more performance. Turbo and engine should be in good condition and not too old.
BAR-TEK® tips
As always at this point we recommend 102 octane as fuel. This makes the engine knock less and gives you more performance. Turbo and engine should be in good condition and not too old.


Immediately ready for shipment!
You need this extra to make it last:
Here you should urgently upgrade to a sports clutch, as the original clutch cannot transfer this power. For the conversion to K04-015 turbocharger you should use a racing catalytic converter and our upgrade air mass meter.
If you have already installed a sports cat, an intake hose and an upgrade charge intercooler, you can simply continue to use them. The sports cat is very important for the 1.8T engines in the Passat and Audi A4.
If you have already installed a sports cat, an intake hose and an upgrade charge intercooler, you can simply continue to use them. The sports cat is very important for the 1.8T engines in the Passat and Audi A4.




Immediately ready for shipment!
You need this extra to make it last:
320 PS is a good announcement! To be able to drive this power, you should replace your connecting rods with H-beam connecting rods. Now a sports clutch kit is absolutely necessary. For the exhaust you should use a 76 mm exhaust system.
A good software tuning of all components is required for this conversion. For this you can send your control unit to us or have your car tuned by us. Another tip from us: You should convert the downpipe to 70 mm, as the Passat and Audi A4 have a very narrow body at the bottom of the axle beam. You should move the catalytic converter downwards. This will reduce the exhaust temperature and protect the turbocharger!
A good software tuning of all components is required for this conversion. For this you can send your control unit to us or have your car tuned by us. Another tip from us: You should convert the downpipe to 70 mm, as the Passat and Audi A4 have a very narrow body at the bottom of the axle beam. You should move the catalytic converter downwards. This will reduce the exhaust temperature and protect the turbocharger!




Immediately ready for shipment!
These values are based on our own experience, but can vary depending on the vehicle. Since each engine is different and the maximum power depends on several factors, we can only give tendencies. If you want to know exactly what power your car is capable of, you can have it tested and tuned on our 1000 PS power dynamometer.
Questions about your 1.8T tuning?
We look forward to hearing from you and will be happy to answer your questions! Call us or send us an e-mail!