MK5 Golf GTI

All Things Mk5 => Mk5 General Area => Topic started by: john87 on April 30, 2012, 12:23:48 pm

Title: Turbo in GTI - K03 or K03S?
Post by: john87 on April 30, 2012, 12:23:48 pm
I was having a glance through Car Mechanic magazine in my mates house the other day, and happen to turn to a page talking about turbo's. The article mentioned something about the Borg Warner K03 turbo running out of puff at 3500 rpm, and that the K03S was the improved model used in many VAG group cars that provides steady power up to 5500 rpm. Needless to say, this  :confused: me a bit as I was under the impression it was the straight K03 used in the GTI?

Just a talking point I know, but anyone info on this would be appreciated  :happy2:
Title: Re: Turbo in GTI - K03 or K03S?
Post by: sub39h on April 30, 2012, 12:38:31 pm
The K03S was only used on the 1.8Ts, and I suspect the article is talking about those.

The standard GTI does indeed use a K03, but people tend to report it running out of puff at 5000rpm or so. The Ed30/Pirelli use the K04
Title: Re: Turbo in GTI - K03 or K03S?
Post by: nezquick on April 30, 2012, 12:51:33 pm
Does that mean the k03s is a straight swap?
Title: Re: Turbo in GTI - K03 or K03S?
Post by: Tamiyoman on April 30, 2012, 12:55:12 pm
I believe the K03s is the same housing just different internals, my old 1.8T was K03s and My brothers 1.8T was an earlier K03, we both had them mapped and on same rollers, mine saw 203bhp and his saw 197bhp and he had the slightly more aggressive map it read 194bhp before tweaking it.
Title: Re: Turbo in GTI - K03 or K03S?
Post by: gazon69 on April 30, 2012, 12:56:17 pm
Does that mean the k03s is a straight swap?
From what i was informed a long time ago is that the k03 from the mk5 is the same as a k03s. They just called it the k03 because there is only two variants on the mk5 where as on the mk4 there was the k03, k03s and the k04 :happy2:
Title: Re: Turbo in GTI - K03 or K03S?
Post by: vRSAlex on April 30, 2012, 07:46:57 pm
K03s is only for the 1.8T.  The turbo is separate to the manifold on the 1.8T's whereas on the tfsi its an all in one unit.  The term K03s came from users rather than from BorgWarner who make the turbos.

There are many many versions of a K03 and K04 turbo used across many manufactures.  The number after the K03/4 defines the model.  So the K04-23 is for a 1.8T with the egt probe in the exhaust housing, where the K04-64 is the tfsi turbo.

Ford transits and Vauxhall astras also use a variant of a K04.