Intersting info on K03/K04 Turbo's

jezyg

Active Member
Feb 21, 2003
2,323
21
Derby
This is from a post on Audi-sport that I am sure many of you would find interesting of a question sent to Borgwarner who make the K0 series of turbo's



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 yóu'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 Grüßen/Best regards,
BorgWarner Turbo Systems GmbH
 

BeezerDiesel

Minus a Diesel Beezer
Aug 3, 2002
1,852
0
Exeter
Visit site
What a really useful reply! Plain English and very helpful, obviously they are the 'tolerances' that they would recommend but funny how they mention re-maps quite openly where as you get used to car manufacturers getting (understandably) arsey about such things.
Well done for posting it up.
 

LEO LION R

if you need to ask . . .
Mar 25, 2002
5,653
0
on the edge
I take in all of that they are only referrring to the KO4s use on a stack 150 or 180 engine, when they say it should not go above 220. Some folks also have said they have 240 from a KO3 ? :cheers:
 

Zamot

Full Member
Jan 11, 2004
152
0
Edinburgh (Norway)
www.zamot.tk
Why do people refere to K03s?
And why is it that some cars come with the socalled K03s, and produce more pressure at higher revs (and mor torque)? A guy (www.tsracing.no) her in Norway who as A LOT of expierience with Audi and the 1,8T engine, says sometimes there is K03s (K03 "shell" with K04 inside) and sometimes K03, but he hasn't figured out why some cars have K03 and some (same car/enginge type) has got the "K03s". He also says you won't know which type it is before you look inside it, because they hav the same VAG ordering number..

Where do I find the number (e.g K03-052) on mye car/turbo?
 

dangel

Nuclear Banana Boy
LEO LION R said:
I take in all of that they are only referrring to the KO4s use on a stack 150 or 180 engine, when they say it should not go above 220. Some folks also have said they have 240 from a KO3 ? :cheers:

Like me? :) It's a bit confusing that reply - not really sure what to make of it. He seems to be saying changing to a K04 doesn't make sense, but we know of one guy on here with 250bhp as a result of doing just that.
I thought there was a K03S - there's quite a few cars post '03 which are chipped to circa 230bhp whereas older cars seemed to produce less?
 

Shock_Xe

Guest
dangel said:
Like me? :) It's a bit confusing that reply - not really sure what to make of it. He seems to be saying changing to a K04 doesn't make sense, but we know of one guy on here with 250bhp as a result of doing just that.
I thought there was a K03S - there's quite a few cars post '03 which are chipped to circa 230bhp whereas older cars seemed to produce less?

:D

He reffering to the K04-01 which is a hybrid of K03 K04 and was not used on production Vags, APR/AMD/Star performance offer this as an upgrade but is very similar to k03s making only 5bhp or so more, however sometimes less as the exhaust outlet is smaller and its more fragile turbo.

the K04's used on vag cars are the K04-20, K04-22, K04-23 higher number being the later/newer models.

I posted this reply on audi-sport also to clear it up and I posted what was said in another thread on here before seeing this.
 

Shock_Xe

Guest
Andy blunt on here has a A3 1.8T 180bhp quattro and just changed his turbo with one I supplied for him, when we took it off it Wasnt a K03s!!! A boggo K03, As suspected by myself as there are only 3 models of K03s as they stated which I myself am using/selling, Found this out 3/4mths ago through various sources. Nice that its confirmed!
 

IbizaCupra1987

SilverIbizaCupra
Jun 8, 2011
91
0
Blackburn
This is from a post on Audi-sport that I am sure many of you would find interesting of a question sent to Borgwarner who make the K0 series of turbo's



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 yóu'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 Grüßen/Best regards,
BorgWarner Turbo Systems GmbH

Further to the question/answers above which of these "so called" k03s is the best option to choose for my ibiza cupra upgrade...thikin the -052 variant but anyone with greater knowledge could clear this up :think:

K03-052 180 hp, 85 N actuator
K03-053 150 hp, 85 N actuator
K03-058 150 hp/180 hp, 85 N actuator
 

Tr1ck

Active Member
May 13, 2011
236
1
Cornwall
This is interesting!they say the ko3 can take upto about 215bhp yet alot of stage 1 or custom remaps say they can take the 180 bhp models to around 225 and still be in safe operating zone of the engine and its components! But does the ways the car is driven also gave an impact on this?
 

LEE69

Stage 2 Revo'd
Dec 10, 2004
21,262
74
C\UK\Devon\Torquay
This is interesting!they say the ko3 can take upto about 215bhp yet alot of stage 1 or custom remaps say they can take the 180 bhp models to around 225 and still be in safe operating zone of the engine and its components! But does the ways the car is driven also gave an impact on this?

The original post is 7 years old, i guess mapping these cars as progressed in that time ;)
 

Tr1ck

Active Member
May 13, 2011
236
1
Cornwall
The original post is 7 years old, i guess mapping these cars as progressed in that time ;)

haa i only just realised that.. must have been as i clicked on new posts at the top of the screen and it was there as the guy above me posted. :rofl:
 
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