KO3 or KO3S ?

[GT3]

Can anyone confirm 100% whether the Polo GTI has a KO3 or KO3S turbo? I've come across information that says the Polo Cup GTI has the same engine as the Audi TT 180HP (fitted with KO3S turbo), but the Polo GTI has the 150HP engine/normal K03. Can we confirm the Borg Warner product codes and work out which is which?

[Quest]

Here is what you want :

[GT3]

what is the serial code on the sticker in your other photo?

[RhysQ]

As far as i know (obvisouly not 100%), the Polo GTI CUP just has a re-mapped ECU from the Polo GTI, no different turbo or anything. That's just from the reviews i've read anyway.

I know that the KO3 is in the Golf IV GTI and we are at the same kW but 10 more Nm (different intake and running gear would cause this) as them so i'd imagine we'd have the same turbo.

The old Audi S3's (~MY2001) run the KO3S and they certainly have more power then us (154kW/270Nm)

[RhysQ]

putting that 5304 101 5089 code into google though brings up many results indicating it is the KO3S....i'm confused??

EDIT: i just looked at his thread on this site, it appears there are some knowledgable people here that have confirmed it is the KO3S - http://uk-mkivs.net/forums/t/71172.aspx

[GT3]

i just looked at his thread on this site, it appears there are some knowledgable people here that have confirmed it is the KO3S - http://uk-mkivs.net/forums/t/71172.aspx

I've read that and none of them are certain.

I've tried Bog Warner's site and it doesn't display anything for 5304 101 5089. What we need is the OEM part number - that might do it.

[VW GTI]

I thought we had the k03s, the MKIV has the k03.

[GT3]

I thought we had the k03s, the MKIV has the k03.

we all thought that, but may not be the case. as soon as quest confirms the OEM sticker number, we'll know.

[VW GTI]

we all thought that, but may not be the case. as soon as quest confirms the OEM sticker number, we'll know.

Aren't you the only one questioning it?

Why not share the information (or source) that is leading you to believe otherwise.

[GT3]

This is a popular and well known quote:

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 http://www.turbodriven.com.

Mit freundlichen Grüßen/Best regards,
BorgWarner Turbo Systems GmbH
Sales IDS - Technical Support
Christian Seibert