View Full Version : KO3S VS K04 Why upgrade?
Petrina Polo
15-07-2009, 03:05 PM
I have been doing a little reading...
My understanding is as follows...
Borg Warner produce a K03 Turbo that is fitted to our cars. (Polo GTi) There are a few different types of K03 Turbo. Apparently an older version, known as the K03 with 12 blades and a revised version with 8 blades and different actuator known in tuning circles as the K03S (but not its official name).
Apparently the K03S can hold a little more boost and flow a little more air.
My reading leads me to beleive the Polo Gti has the more efficient K03S.. but the Mk4 Golf Gti also with a 1.8T the older K03.
My further reading suggests this K03S turbo is good for around 215hp (160kw) without overspeeding the turbo.. The previous version K03 good for 195hp (146kw). APR on its site has different outputs for Polo Gti and Golf Mk4 chipped. (does this confirm the K03 vs K03S)
My reading also suggest that the K04 Turbo which is considered an upgrade for our cars is only good for 220hp without overspeeding the turbo. The K04 has 8 blades of slightly different design which can flow a bit more air.
If what I read is true, what is the point of spending $3000+ to change our K03S Turbo for the K04?
jesum
15-07-2009, 05:07 PM
from what i understand after reading Guy's postings, the k04 is good for top end power. it keeps pulling till redline.
AGO41T
15-07-2009, 05:10 PM
from what i understand after reading Guy's postings, the k04 is good for top end power. it keeps pulling till redline.
i wish my K04 did that :duh:
decat
15-07-2009, 10:17 PM
try to get a K04-001
Gti Dave
16-07-2009, 01:48 AM
Not planning on doing this upgrade anytime soon and I see it as being pointless for my applications since I don't take mine to the track and since traction is already an issue.
Plautos
16-07-2009, 02:21 AM
The turbine shaft is responsible for give power and when it will be released.
You need to understand the exhaust manifold is pressurized, so the cylinder chamber is pressurized and if you have pressure inside the chamber there is some difficulty to make a cleaner air fuel mixture, because there are some remains of the previously burn inside the chamber contaminating the new cycle.
The K03S is saddled with a tiny turbine:
Inducer: 45mm => Area 1589,625 mm^2
Exducer: 38mm
Tip height: 6.8mm
Blades: 11
Compared to the K04 turbine:
Inducer: 50mm => Area 1962,5 mm^2
Exducer: 42mm
Tip height: 6.4mm
Blades: 12
We can see the k04 is 23% bigger, so roughly speaking it is capable to give 23% more power them a k03, because it is capable to do a better exhaust and therefore cleaner air fuel mixture will arrive.
But….
The compressor wheel is tiny, designed to work with a boost of 0,6kgf so it will give pressure soon and fast for the entire rpm range, but when we tune our engines and require more boost, the compressor wheel it is not capable of sustaining it for much long.
So we need a bigger compressor, found in the k04-22-25-29
The K04-001 compressor looks like this:
Inducer: 35mm
Exducer: 50mm
Tip height: 3.7mm
The K03-052 (K03S) compressor is a bit larger still:
Inducer: 38mm
Exducer: 51mm
Tip height: 4.4mm
compressor wheel RS4: k04-25
40mm inducer,
51mm exducer
compressor wheel RS6: k04-29
42mm inducer,
56mm exducer
Now is a question of flow. The right thing to do is research turbo maps and chose which compressor will sustain the pressure desired for the entire rpm range.
There is a lot of variables when you are going to tune an engine and choose the correct turbo, but this is a good start to understand if it worth or not.
In my case, I went for the k04-25, I had to machine the compressor housing to fit the new compressor wheel, in the end it looks just like a k03s and it is totally plug and play. Worth the cost paid.
Petrina Polo
16-07-2009, 11:10 AM
Thanks. Always a quality response from Plautos.
Bboy_Sparx
16-07-2009, 12:53 PM
Holy crap! Talk about a response!! Hahaha
pogo_55
16-07-2009, 02:51 PM
As street cred seems to be high on your list of priorities, you definitely need to get a K04 regardless of how much more/less power it makes than stock.
The problem with the K03s is it has a silencer built into it which all but removes the turbo whistle. The K04 hasn't and has lots of whistle audible at low revs.
Fully sik man...... If you like that sort of thing.
The turbine shaft is responsible for give power and when it will be released.
You need to understand the exhaust manifold is pressurized, so the cylinder chamber is pressurized and if you have pressure inside the chamber there is some difficulty to make a cleaner air fuel mixture, because there are some remains of the previously burn inside the chamber contaminating the new cycle.
The K03S is saddled with a tiny turbine:
Inducer: 45mm => Area 1589,625 mm^2
Exducer: 38mm
Tip height: 6.8mm
Blades: 11
Compared to the K04 turbine:
Inducer: 50mm => Area 1962,5 mm^2
Exducer: 42mm
Tip height: 6.4mm
Blades: 12
We can see the k04 is 23% bigger, so roughly speaking it is capable to give 23% more power them a k03, because it is capable to do a better exhaust and therefore cleaner air fuel mixture will arrive.
But….
The compressor wheel is tiny, designed to work with a boost of 0,6kgf so it will give pressure soon and fast for the entire rpm range, but when we tune our engines and require more boost, the compressor wheel it is not capable of sustaining it for much long.
So we need a bigger compressor, found in the k04-22-25-29
The K04-001 compressor looks like this:
Inducer: 35mm
Exducer: 50mm
Tip height: 3.7mm
The K03-052 (K03S) compressor is a bit larger still:
Inducer: 38mm
Exducer: 51mm
Tip height: 4.4mm
compressor wheel RS4: k04-25
40mm inducer,
51mm exducer
compressor wheel RS6: k04-29
42mm inducer,
56mm exducer
Now is a question of flow. The right thing to do is research turbo maps and chose which compressor will sustain the pressure desired for the entire rpm range.
There is a lot of variables when you are going to tune an engine and choose the correct turbo, but this is a good start to understand if it worth or not.
In my case, I went for the k04-25, I had to machine the compressor housing to fit the new compressor wheel, in the end it looks just like a k03s and it is totally plug and play. Worth the cost paid.
Yip correct!!
The PGTis KO3s is almost the same as a K04 001. The KO4 0032 is the best in the range, the same that comes in the S3 and Seat Cupra...
Pgtis use the K03s
MK4 K03 - 110kw K03s in the 132kw
MK5 - K03s, some BWAs rumoured to have K04.
I had the complete list... ill try to find it.
http://www.vwwatercooled.com.au/forums/images/imported/2009/07/Enginecodesandturbosizesver1-1.jpg
mikepologti
24-07-2009, 01:57 AM
has anyone else managed to fit a k04 25? or anything else for that matter ?
Petrina Polo
24-07-2009, 09:07 AM
Which K04 does APR fit in its turbo upgrade package?
jasn78
24-07-2009, 09:16 AM
petrina i think you will find its the 001
mikepologti
28-07-2009, 01:01 AM
yeah it is the k04 001 im pretty sure. i hear some of the brits atach garrets to theres, cant see the point personally wayyyy to much wheel spin.
Petrina Polo
28-07-2009, 08:44 AM
I read that a Ko3S as in our Gtis and a Ko4-001 is bugger all difference. more lag, questionably a bit more top end.
pogo_55
28-07-2009, 10:06 AM
OK I'll bite.....
Here is the dyno results for 3 polos at a dyno day last weekend.
Anthony Clelland(Polo GTI) - 149.6hp (K03)
Kenny Greig(Polo GTI) - 167.5HP (K04)
Shane Bromage(Polo GTI) - 169.3HP (K03)
So there you have it - bugger all difference, in fact the K03 is more powerful.
Happy Petrina??
But it's not so simple........ You need to compare apples to apples.
The 2 apples are Anthony's car and mine. In fact Anthony's car has a Forge tip and other engine hoses which mine doesn't. Anthony's car has from what I understand the "vanilla" flavour Custom Code map, which is equivalent to any of the other "one size fits all" maps you get from the other chip suppliers.
So the K04 provides my car with an extra 18bhp, which is exactly in the range of 10-20bhp that is often quoted for this turbo.
Now the question is why does Shane's car have an extra 20bhp over Anthony's one. Well this car has 2 relevant differences. A light weight flywheel and a "custom" custom code mapping. Gavin and Jimmy have put a lot of time and effort into tweaking the map to match Shane's engine. I think it is fair to say that some of the parameters would be too close to the edge to be seen as possible or prudent in the "one size fits all" maps you get from the other suppliers.
So with these 2 changes applied to my K04 car I think you would see the difference restored.
As to feeling the difference Anthony has driven Shane's car and I'm sure that he will confirm you can feel 20bhp difference.
I would love to know exactly how much of the 20bhp is obtained from the lwfw. This just might of highlighted a bolt on component which offers a decent power gain.
Anyway, congrats to Shane, Jimmy, Gavin and Custom Code. This must be one of the most powerful K03 Polo's around.
Jimmy, Gavin if I have stated things that are wrong or misleading about your product please correct me. I can assure you it wasn't intentional.
Kenny
Petrina Polo
28-07-2009, 11:33 AM
Not sure if Im happy yet..
did they have exhausts, dump pipe FMIC..
Is your car just Ko4 and nothing else?
Your Ko4 equates to about 126rwkw... Ive heard of a few cars doing mid 135's (ko3s)
pogo_55
28-07-2009, 11:39 AM
They all have the same mods apart from where stated.
Seat intake, Panel Filter, Dump pipe, FMIC.
You can't take dyno figures out of context. The cars with mid 135's would probably equate to Anthony's car on that dyno on that day.
A blufin chipped Golf got this: Steve Wheeler (Golf GTI) - 174.4HP.
Look in the clubs, meets and Events for Brisbane for the full story. Someone was complaining of "losing" 30+ bhp on this dyno.
Petrina Polo
28-07-2009, 11:55 AM
fair enough though... high or low, its relative speaking..
VWindahouse
28-07-2009, 02:42 PM
It was a great exercise for comparison and research purposes!
Same day and back to back DYNO's (same ambient temps) with the same operators. And all the info you supplied Kenny is true and correct :biggrin:
h100vw
28-07-2009, 07:56 PM
It was a great exercise for comparison and research purposes!
Same day and back to back DYNO's (same ambient temps) with the same operators. And all the info you supplied Kenny is true and correct :biggrin:
Anthony's car had the basic Phase 2 loaded on Saturday morning. This is the same point that we started with on Shane's car.
After taking logs of the boost and lambda that were acceptable, we added more timing with the Custom Settings utility. Until the ECU reacted to there being too much and began pulling some back.
I think that with a bit longer to adapt in the car and some extra timing, Anthonys car will produce closer numbers to Shane's.
I don't know that all the 20hp difference is down to the LWFW but I would say that it is responsible for the steep gradient on Shane's plot compared to the other 2 Polo's.
Kenny's plot was pretty 'plump' in the mid range and that has to be the K04.
I did think that the mk5s would have been further ahead of the Polo's. 2 litre engines and 200hp to begin with.
I don't doubt there would be a few more horses in your engine Kenny, with a bit of fine tuning.
Gavin
Without doubt Anthonys car will be up around there, considering it was reloaded 40 mins before its run it did very well IMO. Ask him at the end of the week how it is. With some of the other thigs that has been done to the car in the way of chassis and brake man itll handle something serious. Putting that power on the ground is the big thing , all you Pog pilots will agree with that.
It was great to see 3 Pogs together for comparisons sake. All were run straight after each other thanks to the operator for that. So temps werent in question, it was very interesting to see the drops on the 2nd and 3rd runs with the heatsoak.
Jmac:)
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