Hybrid K04 R&D

beachbuggy

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So there have been a few threads recently on Hybrids, good and bad results have been had, inconsistencies in production to name a few.

What was a good hybrid 2/3 years ago before the High flow tubular manifold, "welly" cooler, mapping improvements now it seems it's quite cutting, part of the issue is that the gap between a stock K04 and Hybrid is getting smaller. Your stock K04 can get upto 300bhp while the Hybrid K04 still has yet to be surpassed at 344bhp and somewhere in between there are supposed to be a stage 2 and stage 3 version...

So can the 344bhp be beaten? and can 344bhp be beaten without WMI? is it really worth trying to do it when a GT28 or GT30 will do it without issue? and is there now still a market for it?

Where am I going with this , well I have no intention of going BT so thought I might have ago at beating 344bhp and aim to develop a bigger and better hybrid.. Question is though , when is a hybrid not a hybrid, well I think that as long it can fit in exactly the same place a stock K04 can fit then it can be classed as a hybrid.

At present we are limited by the compressor housing and turbine housing, but with making these bigger we introduce new issues such as lag, which is one of the Hybrids benefits, in so much lag is kept to a minimum compared to say a Gt30 turbo, making it more drivable ( open to debate )

My aim is to build a more powerful turbo, in a K04 frame.

So there is the first version and please bare in mind this is development item, it is fully functional and is going to fitted to an Audi TT for testing. I am open to all and any comments and don't expect it to make mega BHP from the off but be a start to a finished item even if it is concluded the current hybrids are the best option.
Billet GT35 compressor wheel on a K04 bearing housing with RS6 turbine
photo-144.jpg


Fitted inside a heavily modified K04 compressor housing
photo-150.jpg


GT35 compressor next to a stock K04
photo-145.jpg


Mocked up on the Relentless manifold
photo-148.jpg


GT35 compressor V Billet 2283 compressor wheel
photo-143.jpg


Now this first version was to see if a Garret compressor wheel could be sucessfully mated to RS6 turbine wheel and installed on the CHRA of the K04.

The compressor wheel was machine so that a sleeve could be installed inside the compressor so that it could be put onto the original turbine shaft. as the compressor wheel is held in place in part by the fitting over the shaft but mainly by the clamping force of the nut on the top and the thrustwasher washer. As you can see it doesn't look pretty but it fits, it was send off and fully balanced, twice, to ensure that it would survive spinning at high speeds. Although the compressor wheel is considerably larger that the stock wheel the billet wheel means that it is light and weighs only slightly more than the original stock cast k04 wheel.

In order to get this wheel to fit the compressor housing the original inlet was completely machined out and a new billet inlet was machined. This was then Tig welded up to ensure that it was secure for when the inside was machined and also to allow the radius of the exducer to remain.

Now my intention with this version is to prove the GT compressor wheel can be used, I'm not chasing the numbers here but would like to get over 300bhp at relatively low boost. I am aware that balance needs to be found between compressor and turbine specs. That just because it's big doesn't mean it'll work...

I have also heavily modified the turbine housing to aid flow, I will post some pictures .

Any comments welcome.
 
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I will be keeping a close eye on this thread, that looks awesome mate
 
Love it mate, if you are capable of getting 350bhp onwards from your hybrids i think id be happy togo down the hinrid route again and fit one of these rather than the smaller bt route ive been looking into. Top work man.
 
Sounds good Dan!

I think the key is in the turbine housing though personally, the 2283 is known to flow 370bhp + on the TFSI engines, and it's usually EGT's that stop play on current hyrbids.....

I'd like to think mine could potentially make over the 344bhp if pushed, as it's very similar to Wellys, only optimised further in spec.

We shall see. I think you could have an issue with thrust bearings too, my 2283 turbo has far more in/out play on the thrust than I'd like after just 4000 miles use....
 
Surely the issue here is that you NEED boost because the turbine side is restrictive?

While that compressor will happily flow a zillion horsepower, to get 340hp from a K04 turbine housing, your going to need upwards of 20psi into the inlet manifold, and i suspect that you might be hitting the surge line of that compressor trying to get 20psi?

An Actual GT35 would make 350hp with low boost, because the massive turbine means the engine flows a lot better?
 
I don't know if this will help but i found this on the net

This same turbo was bolted to a K04 manifold

IMG_20110823_084056.jpg

20120308_092311.jpg

20120308_092304.jpg



I don't know what exhaust housing it is but if you can find out it may be a good option for a cheaper BT
 
It's really good to see someone really trying to break the mould and experimenting with these turbo'd be it a success or not :)

Will be following this closely and I'm sure it will benefit everyone with the research....take my hat off to you mate ;)
 
The thrust bearing isn't the issue its the thrust washer it's pathetically small and narrow. build one with a bigger collar and the pressure gets spread over a larger area rather than the 1.5mm it is in stock form.

I dropped one off at the machine shop today, along with the thrust bearing and oil thrower and hopefully they are going to be able to machine a bigger collared thrust washer to help stop the same issue you've had.

With regards the turbine housing,

Here's an eliminator housing I got hold of. It's for an 81mm garret bearing housing and Gt30 turbine, but I think and insert can be made to house the K04 CHRA and also an insert to reduce the internal bore down to K04 size. If I can then find a foundary that can make these up then potentially problem solved.

photo-147.jpg


On this turbo, I have heavily ported the housing, re profiled the exducer port and generally tried to make it flow better. It's never going to flow 350bhp off the cuff without high EGT's but it's worth seeing if it can make a difference.
 
Andrew

I have one of those exhaust housing, bought from a ASN member.
 
Surely the issue here is that you NEED boost because the turbine side is restrictive?

While that compressor will happily flow a zillion horsepower, to get 340hp from a K04 turbine housing, your going to need upwards of 20psi into the inlet manifold, and i suspect that you might be hitting the surge line of that compressor trying to get 20psi?

An Actual GT35 would make 350hp with low boost, because the massive turbine means the engine flows a lot better?

Yes Kev you are right. however if this setup works in so much it boosts, holds boost, and doesn't self destruct then the plan is to work on the turbine housing for the exact reason you are giving.. I could have used a gt28 or gt30 or IHI compressor it was just I got hold of this and thought if I can get this to fit and work then a more sensible Gt28r compressor might be a more realistic option...
 
k04 eliminator from dan's dead 2871

luvin the work dan..

dyno available for your testing foc if you want access to it
interesting evolution
 
Nice work Dan, great to see "out of the box " thinking and could potentially make you a very rich man...:arco:

I will see if my foundry contacts would be interested, but i fear numbers would have to be great...:unsure:
 
all i can see is big respect mate, ill be keeping a close watch on this thread honestly hats off to you... great innovation hope it all pans out fine
 
Interesting stuff again Dan!"

A quick thought for you: I believe when Dan ran that eliminator kit on his LCR it only made around 340bhp at Bills.

I'm not saying 340 is in any way bad, but it is the same as a good hybrid, and I believe it took considerably more boost too. if the 2871 is said to be good for ~370ish then I wonder what was holding it back?

I seem to recall at the time Dan said he thought he had simply reached the limit of flow through the standard ko4 collector flange. How do these compare to larger GT units?
 
Top work and will be keeping an eye on this for sure :)
 
Interesting stuff again Dan!"

A quick thought for you: I believe when Dan ran that eliminator kit on his LCR it only made around 340bhp at Bills.

I'm not saying 340 is in any way bad, but it is the same as a good hybrid, and I believe it took considerably more boost too. if the 2871 is said to be good for ~370ish then I wonder what was holding it back?

I seem to recall at the time Dan said he thought he had simply reached the limit of flow through the standard ko4 collector flange. How do these compare to larger GT units?

Collector flange or Exhaust manifold? Was Dan running a stock K04 manifold or a custom built one as I don't think the Renlentless ones where out when he was using it...
 
Assuming we are talking about the same dan, Dan1720v, he was using a v2 relentless manifold. I think he was implying that the flange of the collector on the relentless manifold (the same size as the inlet to the ex housing) had reached it's upper limit of flow at 340bhp. it is only about 44mm isn't it?
 
Wow this is awesome mate, even if your R&D comes up with a decent spec hybrid K04 which is reliable every time unlike some of the turbo hybrids you hear about. That would be good!

Top work!
 
Loving the fact you want to push the K04 to new limits. I for one am very interested in how this works out!
 
The biggest issue with the K04 is the heat it generates due to the amount of boost people run to achieve the figures they want. A hybrid that can produce nice figures with relatively low boost (low for a K04 anyway) will be a winner. It should make for a more reliable setup that wont trigger EGT protection every time it spools up.
 
I look forward to seeing the results

Im a believer of making the engine more efficient with head work, cams, inlets etc anything to increase flow. Has any done lots of head wok added cams etc and still using a hybrid ko4
 
I look forward to seeing the results

Im a believer of making the engine more efficient with head work, cams, inlets etc anything to increase flow. Has any done lots of head wok added cams etc and still using a hybrid ko4

My AEB head only had the usual refurb work and I kept the BAM cams for it. Unfortunately all the info around N/A cams and piston compression ratios came up on this forum after I'd done my rebuild. I will get a better idea of what my K04 can do in 2 weeks time when it gets remapped for 550cc injectors and all the flow mods i've installed.
 
Will be keeping a close eye on this thread...

Keep up the good work and thanks for sharing :)
 
Heat issue come from not getting the air in but out the other side. You are forcing the air in through an ever decreasing scrol in thè turbine housing, as the exhaust gasses slow down, the expanded and thadds lows flow and the backup adds heat. Put your finger over a bike pump and it gets hot as you squeeze it. For the engine to make the same power at lower boost it needs more a larger amount of air.

Now I may be wrong but to make say 340bhp you need x amount of air, whether that be high psi/low volume or low psi/high volume the amount of air in the cylinder will be the same. When that's compressed the result is the same.this is why the agu large port makes the same power from less boost. Please correct me I'm wrong.

The turbine housing I'm using on this one has been , probably or ported and reprofiled possibly to its detriment but the idea is to get the gasses out with less restriction .

Benefit of low boost/high volume flow is lower temps which equals more timing.
 
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So basically "flow" is the order of the day! We have seen great leaps in performance over the last 12 months with the introduction of the XS maifold, 3" DP, and 3" TIP. The Large port head then improves flow even more, leaving only the turbo as the main restriction. Open that baby up and we have some nice gains to be had.
 
To add a little perspective to this...I am currently running on actuator pressure (15psi give or take) and getting 256gs at 7.4k rpm from my GT30... thats 320hp worth of air... however you will loose out on torque without running the boost on a little 4 potter....

<tuffty/>
 
To add a little perspective to this...I am currently running on actuator pressure (15psi give or take) and getting 256gs at 7.4k rpm from my GT30... thats 320hp worth of air... however you will loose out on torque without running the boost on a little 4 potter....

<tuffty/>
Cheers tuffty, That's good to know. would be interesting to see that if I can get similar airflow from similar boost whether the egts would be the same as running the same airflow from a 2283 compressor at 21psi.
 
Cheers tuffty, That's good to know. would be interesting to see that if I can get similar airflow from similar boost whether the egts would be the same as running the same airflow from a 2283 compressor at 21psi.

Mine are low 700's on full chat measured in the DP just past the turbine so in relation to a K04 then this would be around 50-100 deg lower than having the probe where it is in the K04 housing...

<tuffty/>
 
40mm diameter hole to flow all of this....
csa of 1256mm^2mm

Anyones who listened to my boring mantra, will know its one of the key things I work towards.... "Its all about the flow" not about the boost per say

52mm Tial hotside on GT3x turbos in comparison, csa 2122^2mm
(I am flowing 12psi on hybrid GT35/62 - 360bhp, 22psi-460bhp, 26psi 580bhp thru this 52mm diameter tial hotside)
 
sorry to be a dunce , by CSA do you mean curved surface area? and is the 40mm in relation to the stock k04 housing?
 
sorry yea, cross sectional area I meant.. my bad..
40mm measures stock k04 hotside and relentless collector bore internal diameter
 
dan your like the gandalf of turbo's, keep up the awesome work man!

i still need to get you an email with the power graphs in, i will get on that for you as soon as!
 
40mm diameter hole to flow all of this....
csa of 1256mm^2mm

T25 flange internal csa being 2092^2mm

52mm Tial hotside on GT3x turbos in comparison, csa 2122^2mm

T3 flange internal csa being 4080^2mm
 
40mm diameter hole to flow all of this....
csa of 1256mm^2mm

Anyones who listened to my boring mantra, will know its one of the key things I work towards.... "Its all about the flow" not about the boost per say

I said that yesterday Bill, but I'm far less important than you so nobody listened to me :laugh:

Interesting that the difference in csa is quite that much!

he was implying that the flange of the collector on the relentless manifold (the same size as the inlet to the ex housing) had reached it's upper limit of flow at 340bhp. it is only about 44mm isn't it?
 
40mm diameter hole to flow all of this....
csa of 1256mm^2mm

T25 flange internal csa being 2092^2mm

52mm Tial hotside on GT3x turbos in comparison, csa 2122^2mm

T3 flange internal csa being 4080^2mm

Oh thats interesting didn't realise the tial one was that small?

Did you notice it create much back pressure on the badgerwagon and effect egts compared to the T3?
 

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