1.8T turbo swap, K03S

[DaniS4]

Soooo... Can I just replace the stock K03 turbo (150hp) for a K03s (180hp) and thats it? (I would replace the TIP too for a high quality silicone one).

Is this as simple as that or should I change anything else?

Also: any reliable shop to get a new K03s? (not chinese copies, etc).

Thank you very much :D

p.s. my car is not chipped. 100% stock power and components.

[Ozone510]

From my understanding all B6 had K03S, if you want an upgrade that is juick and easy, grab a K04 and some injectors, I have a spare k04 for yah if you want it, just needs a rebuild.

Sent from my Pixel 7 Pro using Audizine Forum mobile app

[grayjay]

You can change to a slightly larger turbo without making other hardware or ECU changes and it will still function at the stock performance (boost) level. Performance is dictated by the ECU tuning, not by the small stock turbo. You cannot change to use different size injectors for more performance without also changing the ECU.

The small stock turbo and injectors would become a limiting restriction if you were to try to tune the ECU for power levels much higher than stock.

The KO3s turbo is still pretty small and will offer minimal upgrade tuning potential, not worth the cost if your intent is to also make the other tuning changes to increase performance.

[EuroxS4]

K04 would be an upgrade, However if going that route I would recommend audi tt 225hp fuel injectors and a different TIP. Note most of the TIP's i've tried fit poorly or came off and refused to stay on fitment wasn't the best of any of them. That includes samco silicone one as well. So just be ready to make things work a little bit. Of course any hardware changed required ecm reflash otherwise its pointless. Best of luck.

[Ozone510]

K04 would be an upgrade, However if going that route I would recommend audi tt 225hp fuel injectors and a different TIP. Note most of the TIP's i've tried fit poorly or came off and refused to stay on fitment wasn't the best of any of them. That includes samco silicone one as well. So just be ready to make things work a little bit. Of course any hardware changed required ecm reflash otherwise its pointless. Best of luck.

I've had the 034MS to regular sized MAF, worked well, slipped of once due to a leaky CHRA, and I've used the one that comes in Frankenturbo kits with larger MAF and those never slipped off once.

Sent from my Pixel 7 Pro using Audizine Forum mobile app

[egovreau]

Once upon a time, FCP Euro has a K04 for around $850...of course this was before COVID and double digit inflation.

Nice thing about FCP, lifetime warranty!

If you buy from BW, they insist on having a qualified shop install or their warranty is void.

I installed a Forge TIP and have never had a problem with it coming off. I did, however, have to cut it down to get it to fit behind the front clip and all of the smaller lines as well.

Sent from my SM-S918U using Tapatalk

[Kevin C]

I swapped to a K04-064 (turbo for the B7 2.0TFSI). On a stock tune no real difference in peak HP but the throttle response and low RPM TQ was a lot better than the stock K03 my 2003 came with. the swap requires an adaptor flange for the exhaust port, B7 TIP, bypass valve and a converter from a B7. Even the B7's K03 is a drop in and decent upgrade over the B6's K03. The split exhaust manifold design really helps with TQ. Also, the B7 turbo setup really simplifies the inlet setup with the bypass valve built into the turbo. Some small plumbing adaption are needed but it was not all that hard.

[canonball]

K04 would be an upgrade, However if going that route I would recommend audi tt 225hp fuel injectors and a different TIP. Note most of the TIP's i've tried fit poorly or came off and refused to stay on fitment wasn't the best of any of them. That includes samco silicone one as well. So just be ready to make things work a little bit. Of course any hardware changed required ecm reflash otherwise its pointless. Best of luck.

Seriously, what is the deal with this?! I went through two completely different TIPs and both fit like shite. I got so fed up with both of them and ended up putting the original back on.