Club G40 Forum

Technical => Turbochargers => Topic started by: vwmk3jon on February 16, 2015, 01:59:54 pm

Title: K03 part numbers
Post by: vwmk3jon on February 16, 2015, 01:59:54 pm

need a new turbo as im pretty sure mines now goosed after it was rebuilt (not by me i may add) and now only boosts at 0.5bar

anyway... i see turbos listed as K03-*** with three numbers. what do these mean and which is best?

cheers

Title: Re: K03 part numbers
Post by: Andy on February 16, 2015, 06:19:17 pm

From memory:

K03-005 - the most common 150bhp 1.8l 20v turbo from a Passat or A4.
K03-029 - turbine side is larger than above, so boost threshold is higher but flows better at higher rpm than a -005.
K03-073 - from a 190bhp A4, is a -029 turbo with a larger compressor. Kind of a 'K03s' for the longitudinal engines.

With the 268° turbo cam I think the common K03-005 is a great all rounder. The -029 is handy if you're happy to sacrifice a touch of responsiveness for a few more bhp and I quite liked it. The -073 is what I run now, biggest issue I have is getting the Forge actuator to control boost properly at 21psi without creep.

Title: Re: K03 part numbers
Post by: vwmk3jon on February 17, 2015, 05:15:42 pm

Thanks Andy ;)

mines not boosting at all well now. still sits at 0.5bar boost and sounds as tho its loosing boost (leak) somewhere but ive checked the pipes ive removed and theyre all tight as hell so im putting it down to the turbo being royally fubared.

Title: Re: K03 part numbers
Post by: GR40 on February 17, 2015, 11:33:42 pm

Did u check the small pipe under the black plastic tube leading to the idle valve? I once forgot to put a clamp on that and the car would stay exactly at 0,5bar no matter the rpm. I could hear it hissing from inside the cabin and took me a while to figure out where the leak was cause it was under the manifold where I couldn't reach or see!