The stock turbo porting thread, or make your K03 suck a lot less.

[gdoggmoney]

/* WARNING IF YOU ARE RETARDED DO NOT DO THIS */

That being said, it is labor intensive, tedious, requires a good eye and hands as well as an understandnig and feel for the 1/4" die grinder spinning at 30,000 RPM. You also have to get the turbo off your car, probably cut off some of the rusted in bolts keeping the CHRA attached to the turbine housing, and not get crap into the oil/water ports etc.


Materials:

1 K03 turbine housing in good shape. They all crack in the center, don't worry just port it.
2 Carbide Burrs, I prefer Titanium nitrided units. They last longer
1 bottle of cutting oil/wd40/whatever kind of lubricant
1 1/4" die grinder, air or electric.

Since this creeps up occasionally, we might as well have it out here. This is the third turbine housing I have gutted and ported. My logic has changed each time, and so have my results quality wise. THIS ABSOLUTELY MAKES A HUGE DIFFERENCE. Anyone saying you gain .5hp obviously has not done it. I put down 230whp on E85 years ago with a high flow manifold and a gutted k03 pushing 20psi with boost oscillating. It had a lot more timing and boost left in it. The dyno is here and the curve was very nice. Shifting your powerband higher is a good thing, these cars lack serious top end as the honda folk call it. This is 100% how this casting should have come from Borg Warner/KKK and how it should have been stock on these cars. Look at the thing and see how much time machining would add to the cost of each turbo, bear casting limitations in mind and then understand why your stock turbo sucks so bad.

First one I did? Measure thrice cut once dummy. I took too much out the wastegate and it did not shut without a gap. In retrospect I would run it because now I want to get as much exhaust out of the half dollar size restriction and into that 3" downpipe no matter what. Also, these things spool so damn early I don't think you can do too much harm, and only gain powerband up high. Second one I took too much off the inside wall closer to the CHRA. It was semi ugly, kind of lumpy but made a huge difference.


This is the third one. I have spent about 8 hours on it total. I am extremely happy with the results. No lumps, very smooth. In these pics it needs sandpapering yet just to smooth the surface some.

I started by simply using a burr to open the inlet to gasket size about a little over a quarter inch in. Then I started raising the roof of the wastegate hole, blending it so the turn over was smooth with no edges, and getting rid of the giant lip in the wastegate. Some castings are worse than others, which is probably why some cars have boost spike issues and others not so bad. The wastegate can be opened DRAMATICALLY allowing more exhaust out, allowing you to run a good bit more boost and not have excessive EGT's.










Stock junk!

[bagtf3]

I'm interested in this. Does the k03s casing suck as bad as well? or just the k03. What about k04 frames? I am assuming there is something to be gained on all the stock framed turbs.

Could you post some graphs or anything boost levels vs rpm, egts, etc?

I want to take one of these to the shop and chop it out with a cnc and see what it can do.

[gdoggmoney]

I'm interested in this. Does the k03s casing suck as bad as well? or just the k03. What about k04 frames? I am assuming there is something to be gained on all the stock framed turbs.

Could you post some graphs or anything boost levels vs rpm, egts, etc?

I want to take one of these to the shop and chop it out with a cnc and see what it can do.

\



Don't have a pyrometer/gauge, or anything to log with. My VCDS went with the last laptop. This is a k03S casing by the way. I think the k03s and k03 use the same hot side wheel and housing.

You do gain some boost approaching redline with this. The other thing is my flash tune used to spike 22psi and then 19psi. Now it spikes 19 settles down lower to 15-16. No logs of requested vs actual and etc.

I'm adding an MBC to fix that inline with the N75.

[l88m22vette]

Because if he breaks **** it doesn't matter Good work man, and seriously, 8hrs?! Commendable, I have a hard time doing anything for 8 hours aside from sleeping

[groundupjetta]

Nice thread

I'll be doing this to a k03s that I'm on the process of rebuilding right now. Thanks for the pics bro

[bootymac]

Nice work. For an idea of gains, here's what Eurotuner dyno'd with the Kinetic high-flow manifold on a K03S with GIAC software and bolt-ons:


http://www.eurotuner.com/techarticle...18t/index.html

[Cryser]

One thing to add to this is watch out when wastegate porting and using off the shelf tunes.

I know my K03s wastegate was opened a lot and I had to lower EGT threashold valve a good amount to avoid running lean for about 300-500rpm after the load stabilized(so no more fuel enrichment or accel fuel) but the full lambda map wasn't triggered yet it would try and target 14.7 with 20PSI leaning to 15.5-16 AFR actual. That would be the case for about 300rpm then the target and actual would drop like a rock, since lowering my EGT threshold I've gotten it to the point where is only gets to about 13.8 so I'm slowly lowering it a few degrees between being able to get a full throttle run data logged.

just something to think about.

But some things I noticed with porting the turbo is the ability to hold more boost in the higher RPMs. I don't have a spike like I did with the k03 when it wasn't ported, I'll hit 22PSI and have it slowly taper to about 15PSI at 5K then down to 13 at 6.5K but never is it the fast drop off like the stock port k03.

[All_Euro]

One thing to add to this is watch out when wastegate porting and using off the shelf tunes.

I know my K03s wastegate was opened a lot and I had to lower EGT threashold valve a good amount to avoid running lean for about 300-500rpm after the load stabilized(so no more fuel enrichment or accel fuel) but the full lambda map wasn't triggered yet it would try and target 14.7 with 20PSI leaning to 15.5-16 AFR actual. That would be the case for about 300rpm then the target and actual would drop like a rock, since lowering my EGT threshold I've gotten it to the point where is only gets to about 13.8 so I'm slowly lowering it a few degrees between being able to get a full throttle run data logged.

just something to think about.

But some things I noticed with porting the turbo is the ability to hold more boost in the higher RPMs. I don't have a spike like I did with the k03 when it wasn't ported, I'll hit 22PSI and have it slowly taper to about 15PSI at 5K then down to 13 at 6.5K but never is it the fast drop off like the stock port k03.

This is interesting - I've recently ported mine… not the wastegate thought… but what are your EGT's and how are you adjusting things?

I've noticed stronger low/mid level pull but currently boost requests aren't being met up top - it may be the wastegate actuator needs adjusting as a different one went on with the ported hot side.

Considering how cheap these turbos are this is a good way to free up some power and do some experimenting. Having an extra turbo lying around as a backup doesn't hurt either

[All_Euro]

Actually, I've got a bunch of pictures too - here are a few…


Loose mani & turbo bolts before I even started… good thing they were coming out.


Hotside after porting - decent for a first try but more material could come out & could be smoother.


Housing comparison. I had the ported housing ceramic coated since it was already off & inexpensive. The coating really exposed the flaws in my work!

[Cryser]

I have maestro so I'm adjusting through that I believe I'm down to 414.5*C as the threshold.

[Big_Tom]

that k03 was opened up a lot

[All_Euro]

I have maestro so I'm adjusting through that I believe I'm down to 414.5*C as the threshold.

Ah… I thought as much but thanks for the threshold temp

that k03 was opened up a lot

Haha, I just gasket matched the opening actually and then shaved off the blob of metal you can see in the OP's second last pic


To the OP - did you happen to take any measurements of how much material you took off?

[Rivals Inc]

I am planning on doing this to my turbo in the summer. I have already ported and polished my intake manifold. I am just wondering if this is the same way as far as doing it. Does it matter how much you take off to the fact when is too much? How far are you suppose to go in? and what kind of tools did you use? I assume the same as for the intake, but maybe not.

[gdoggmoney]

I am planning on doing this to my turbo in the summer. I have already ported and polished my intake manifold. I am just wondering if this is the same way as far as doing it. Does it matter how much you take off to the fact when is too much? How far are you suppose to go in? and what kind of tools did you use? I assume the same as for the intake, but maybe not.

Basically, you can do it by eye, and the only pitfall is to avoid opening the wastegate hole too much so that it will not sela or there is not enough lip to seal.

I used TI nitride coated rotary bits and grinding stones, as well as flapper sand drum rolls to finish out rough gouges.

[Rivals Inc]

Would it make sense to use something like a micro meter?

[badger5]

the actual k03s hotside wastegate opening is 29mm. bigger than k04's which are 24mm

I run a special hybrid k03 on our test car, stock k03s hotside, but with RS6 k04 turbine wheel in there.. and billet 2283 comp wheel in a k04 comp housing with k03s outlet elbow welded to it.
332bhp from 21psi...

I left the k03s hotside bog stock as a test to see how it went.. surprisingly well as it turned out.
EGTs are high when running >21psi, in the 950'c zone measured in the collector. Ex manifold it sits on currently being one of dougs big bore ones.

Makes me wonder if I tickle the hotside on our test one, what might be gained.. Hmmm.

[Rivals Inc]

I have a Ko4 running 24 lbs of boost. But from what im reading when you do this you get a better high end gain. which mine could use since all my power is low to mid range.

[gdoggmoney]

the actual k03s hotside wastegate opening is 29mm. bigger than k04's which are 24mm

I run a special hybrid k03 on our test car, stock k03s hotside, but with RS6 k04 turbine wheel in there.. and billet 2283 comp wheel in a k04 comp housing with k03s outlet elbow welded to it.
332bhp from 21psi...

I left the k03s hotside bog stock as a test to see how it went.. surprisingly well as it turned out.
EGTs are high when running >21psi, in the 950'c zone measured in the collector. Ex manifold it sits on currently being one of dougs big bore ones.

Makes me wonder if I tickle the hotside on our test one, what might be gained.. Hmmm.

332bhp, so crank not wheel? Either way, that is pretty impressive. When I did this each time it felt like I shifted the power band higher super slightly, but more than that it sort of made it no fall off a much, with a super barely noticable hit at like 1500rpm-1700rpm where full spool begins stock.

It's been a while :x

I have a 230whp dyno from one of these on an APR 100 tune with a 3" maf and 630cc injectors and adaptation channel fudging. From before Uni stage 1/2 with exhaust were getting a good bit over 200whp.

[Rivals Inc]

I have ported mine. I will post pics later and i have the ko3s. Im trying to fix a stubborn exhaust leak.