Hey,
There is a brand new K04 turbo on my craigslist locally. It is selling for 350 dollars and comes with all gaskets and hardware for install.

I know I can not just put this on my stock ultrasport and run it. I know I need injectors and a tuned ecu but I am having trouble deciding what to do. Any help would be greatly appreciated.

 

Are you running tiptronic or manual tranny? Besides the price is there any other reason you want the K04?

 

Only reason I ask is because not a lot of people are fond of the K04's harsh torque spike.

 

Make sure that ko4 is in a good condition and for our 1.8t engines, not for TT or VW.

 

I have a manual (6sp).... I just want some more power. I heard the K04 upgrade was the easiest and least expensive turbo upgrade. I have looked around and I think it is the best thing to do. What do you mean by torque spike? Just to much torque for the stock transmission?... Or?

 

Ko4 is an upgrade if you have a b5 with a ko3. You have a b6 with a Ko3s, which is basically ko4 guts in a ko3 housing. Its not really an upgrade.

 

How the hell do you figure that the K04 is an upgrade for a B5 and not a K03s?? My B5 came with a K03s and doesnt mean theres a power difference between mine and a ATW or AEB engines. Once tuning is calibrated to the stock turbo the difference is ~5chp, which is hardly noticible on a butt-dyno. And it is a an upgrade even on a AMB engine. HP is up to ~250 and torque at ~280 with supporting mods. What Kwik_shift is talking about is that there have been cases where the K04, being such a small turbo spools very fast thus creating an insane torque spike which have been known to snap connecting rods which result in a open head surgery. For the $$$ and time spent on a K04 i'd rather get the APR 1+ and have little less power but more reliability for less $ and headaches. The only reason I would get a K04 is if my K03 sh*t the can and I needed a cheap replacement (not upgrade). The K04 can be ran w/o software but you won't see any gains since the mapping is still being sourced for a K03. BTW, what brand is that K04??? If you would STFA a little more, you would find out that the K04 sucks if you're looking for more power and the best thing for the $ and practicability for a new enthusiast is the GTRS. Great quick spooling turbo with mediocre high end. Puts you easily at 250awhp. All be had for under $3,000 too. The K04 moderately built will be around $2,000 either way

 

Wow... Thanks guys for the information. I think I will stick to my stock turbo for a little while then. I think for now an ecu, intake, exhaust, and new diverter valve would be fine. But I might consider buying that turbo just in case.

 

Euro2nr,fore you continue to jump all over my ****. We weren't discussing the final model year of the b5 which did come with ko3s. We were discussing ultrasportdemons B6. If you did some research before asking me how the hell, you would find that you could get damn near the same power out of the ko3s and the power comes on much smoother. The ko3s is not the same as the ko3. I just think its a pointless waste of time, money and effort. Its not just me that thinks so, our own newb guide states as much.

From our own forums newb guide:

K04- easiest and most reliable replacement turbo. It is a direct bolt on replacement. You don't need to replace anything but it is strongly recommended that you get new programming. The most popular is GIAC and with it you will also need a 5 bar FPR. GIAC also offers 3 aggressive files PC-16 for Pre '00, J31 for '00, and Hammer for '01. They are each different but all require an adjustable FPR, bigger injectors, fmic, and you will most likely need a new clutch soon after. If you have a B6 or B7 A4 the k04 is a pointless upgrade. You will only gain a 5-10 hp because of the k03s. It has a 1mm bigger wheel shaft, and more aggressively angled fins on the compressor wheel so it can hold more boost more efficiently. A big injector file for the k03(I'm sure whoever wrote this post meant ko3s) will put out almost the same numbers as a k04 setup. k04 will max out around 250hp

So like I stated in my first post, if you have a Ko3s(which all 1.8t B6's come with stock) the Ko4 isn't really an upgrade.

 

Thank you! That is what I wanted to know. If it will not be worth the money I will just go with upgrades on the stock turbo for now. I don't want to waste that much money on a turbo upgrade if I don't have to. But I do have another question. If I upgrade my injectors and fuel pump on the stock turbo with the ecu, intake, diverter valve, and exhaust... will it have an effect or should I just not do it and wait for a new turbo?