Iar diferentele dintre tipurile de turbo K03, K03s si K04:
The Question Can the K03 turbo (5303 988 0011 or 5303 988 0053) be directly replaced by the
K03S (5303 988 0052 or 5303 988 0026) in terms of the intake and exhaust housing
dimensions?
Is K03S the correct designation for the latter turbo mentioned above?
Obviously if a K03S was fitted an engine map could be changed to suit, but would
a standard turbo map for the K03 be suitable for running a K03S on?
or would a loss of power be expected? and are the characteristics of the two
very similar?
I hope you can assist with the above and any information you could supply would
be gratefully accepted.
It's taken me a couple of weeks to get a response, but the response was well
worth it, I think y?u'll agree.
The Answer Dear Sir,
thank you for your interest in our products.
First of all, we don't produce any turbo that we call K03S. But I hope I can
answer your questions with the following explanations.
All the following turbos have the same installation dimensions and
thermodynamical performance. The differences are only in the actuator that
opens the turbine bypass valve:
K03-011 (5303 988 0011) 150 hp, 65 N actuator
K03-026 180 hp, 85 N actuator
K03-035 180 hp, 85 N actuator
K03-044 150 hp, 65 N actuator
K03-045 156 hp (Ibiza Cupra), 85 N actuator with 2 ports
K03-049 150 hp (Sharan/Alhambra), 65 N actuator
The 180 hp versions have an actuator with a higher opening force due to the
higher exhaust gas pressure (which is a consequence of the higher boost
pressure). Otherwise the valve would be pushed open by the exhaust gas
pressure.
The following turbos are a further development (since 2000) and have an
improved and slightly larger compressor while using the same turbine (still
with the same installation dimensions):
K03-052 180 hp, 85 N actuator
K03-053 150 hp, 85 N actuator
K03-058 150 hp/180 hp, 85 N actuator
Consequentially, putting a 180 hp turbo on a 150 hp engine will not bring
about any change in performance, but putting on a K03-052/053/058 instead of
the older versions will bring a slight improvement in engine efficiency.
Additionally, with re-mapping the ECU you can achieve about 215 hp without
danger of overspeeding the turbo. With the older turbos, 195 hp is the
limit.
With the K04 that's also commonly used (5304 950 0001) the power output
should not be more than 220 hp. That means, changing a K03-052/053/058
against a K04 does not make a lot of sense.
I hope that these details answer your questions. If you need more info, one
of our service distributors will be glad to help you. Their addresses are on
our website
www.turbodriven.com.
Mit freundlichen Grussen/Best regards,
BorgWarner Turbo Systems GmbH
And a post ....I've had a K03, K04 and K03S and the above comments just don't ring true. I don't want to get into the BHP numbers achieved other than to ask if the figures quoted are flywheel or wheel figures as most US tuners tend to only quote WHP.
The K03 and K04 are dated weak turbos in comparison to the K03S. The K04 can move more air than K03S at the same pressure, however the K03S is considerably stronger so can run higher levels of boost. From what I have seen comparing BHP figures there is usually only around 5bhp difference in peak power between the K03S and K04. The big difference is the K03S' stronger midrange and much higher torque. If the two turbo's rolling road graph's were compared the following would be observed:
K03S - Torque comes in early and with a big spike, holds well in the midrange but drops off towards the end. This is reflected in the power with a steep rise but flatenning earlier.
K04 - Torque comes in later due to later spool up, spike isn't has high but torque is flat and holds upto the higher revs. Power is more uniform upto the high revs.
The end result is peak power is about the same for both, they just get there in different ways.
As for the K03 it's a bit pants, low torque and not much happening after 5krpm. With just a remap they give about 185-190bhp with loads of other mods you should be happy if you break 200bhp.
