500 BHP with a K26/7????

[Costash]

I used a mechanical flaring tool that expands as you wind a tapered bolt into a section of wedges, sorry kinda hard to describe properly.

It was easy, took about five minutes. I used that hose as an experiment as it's a bit tatty so it didn't matter if I ball's it up but as it happened it worked just fine, main thing is to get the rubber just hot enough to stretch but not melt.

I get that ,what about the red hose in your pics how is holding on boost ?

[Quattronaut]

Right then it sounds like the "3071 O" is what I need to go for, 2.5 Bar @ 3300 RPM sounds awesome! Is that using 98 Ron fuel on a stock 2.2 or has he up capacity or used different cams?

Stock capacity, 98ROZ, no WMI or other "games", just boost. Cams were NM, 7A, and similar combinations, with similar results.

So far I've spent very little on the two turbos I purchased to make that hybrid with an #8 hot-side, I can probably recoup most of it on the remains of the Porsche K26 and the various oil and water pipes that came with it. Effectively making it free before machine work, balancing, the 3071 wheel and a rebuild kit which will add up but won't be as much as yet another turbo.

What turbos do you have? AFAIK one of the guys I know took exactly this K26/ 3064 "G" turbo you have as base for his one, and is was easy way.

[K Simmonds]

I get that ,what about the red hose in your pics how is holding on boost ?

That's my emergency spare RS2 turbo/inter-cooler hose, it won't be the one I use when I install the engine I'm going to build up over winter.

[K Simmonds]

Stock capacity, 98ROZ, no WMI or other "games", just boost. Cams were NM, 7A, and similar combinations, with similar results.


What turbos do you have? AFAIK one of the guys I know took exactly this K26/ 3064 "G" turbo you have as base for his one, and is was easy way.

Cool, I'm planing on using the original 3B cam's that came with that head, they were happy in there since the engine left the factory so I'd rather not disturb things. Can't see it making a lot of difference if anything they should pick up better low down than 7A items maybe at the expense of a small amount of top end.

I wanted to avoid WMI as it's more expense and if it goes wrong could spell disaster, plus the guy who's likely to be mapping the car doesn't like it.

I have the K26/27 '3064' hybrid in the photo's which has been recently rebuilt and came with a decent #6 hot-side housing fitted. I also have a Porsche 944 S K26 in great condition which I purchased solely for it's #8 hot-side housing. Got them both for very little money.

As you can see in the photo's the exhaust turbine has been back cut on the hybrid whereas the one in the Porsche K26 hasn't been touched and is in perfect condition. Which would you use, assuming the shafts are the same which they should be right?

[Quattronaut]

As you can see in the photo's the exhaust turbine has been back cut on the hybrid whereas the one in the Porsche K26 hasn't been touched and is in perfect condition. Which would you use, assuming the shafts are the same which they should be right?

The 3071O wheel is extremely stable in term of surge, but there was one guy who had surge problems. The manufacturer of his turbo could not solve the problem. At last, the turbo-guy I know had a look to the turbo and saw, that the turbine wheel was original KKK, but had this back-cut for more flow, done by the manufacturer of that turbo. He threw it out, and took a complete original one. No surge any more.
Back-cut may give a little more flow- but it decreases efficiency of the whole turbo, and in some cases, it may cause surge. To be honest- don´t you all think, a leading brand like KKK knows their own turbos best? They engineer it. If some back-cut will make the whole turbo better- they would add it themselves. IMHO it is the best way- keeping that turbo completely original.

[K Simmonds]

That makes sense, thanks for the advice. I don't want a problem with surge so I'll carefully strip the Porsche K26 down soon and use it's turbine and shaft, assuming it's in good condition of course. It should be as the turbo had covered 114K miles before being removed, has no shaft play and is nice and smooth and the car it came from was running fine.

I'll try and remember to take some pic's so other members can see what's involved.

[SteveH]

Ok, great you found the dimensions. The K26/27 naming is indeed crap- as if you say "I´m drivin a 5cylinder". It can be from 1,9 to 2,5L, NA or charged, 4 or 2 valves...

KKK names it´s turbos after turbine inducer. K26 "family" is 64,4mm. K24 is 59mm. BUT: every turbine is available in different "contours", or shapes (mostly there are 4). Exducer diameter is signifantly important for flowing capacity.
S2 turbine for example is "countour 3", which inducer/exducer ratio is 74%, giving 59mm/~43mm diameter. Good for spoolup, bad for high power numbers. RS2 turbine also is K24, but "contour 2", the biggest one, with 89,5%, making 59mm/53mm diameter. The commmonly used K26 wheels are "countour 1", with 87%, making 64,4mm/56mm. You see- K24 RS2 turbine exducer is nearly as big as the K26 one, but the wheel itself is much smaller and lighter (226g to 291g), giving it faster spoolup with nearly equal flowing capacity.

The K27 compressor wheels are the 3" ones, 76mm. And even there are several ones.
K.Simmonds, your 76mm/48mm wheel is the old 3064"G" wheel from the BMW 745Diesel, designed in the 70s and debutated in 1981. It can flow 0.27m³/s air, exactly the same amount of air as the 2672"G" wheel from the RS2 turbo can flow. It does not give you an advantage to the RS2 turbo, but is heavier and more laggy.

SamSam´s 3071 "G" is the same style wheel, but bigger, it can flow 0,315m³/s. Able to do 430-440hp, as he told.
Modern 3071 "O" style wheel: 0,355m³/s, able to do 470-480 hp.

I would not try the 337 and 3375 wheels, I think your housing is too small, and your turbine, too.
I´d try the 3071 "O" one. I know a guy who´s driving that combi with 2,5bar@3300 rpm and around 450hp.

Sorry for the thread hijack

I have the old Svensk TurboService KX500 26/27 like Sonic. The specs are:

inducer diameter 54.8 mm.
back wheel diameter 76.0 mm.
Compressor trim 72% (0.5 to 1.50 Bar)
Compressor house outside diameter of 170.0 mm.
Single Flow entry turbine.
Turbine Wheel: Exducer diameter 54.5 mm.
turbine: Size 10.0 cm2. (No 8)

The compressor wheel is old school and could really do to be a billet item with a modern design.

http://i.imgur.com/fNbiBS6.jpg

When Albert was supplying 26/27's he suggested something like a billet item IN 56mm, EX 78mm, TIP 81mm would fit.

Any suggestions for this hybrid and where I might source parts??

[vidar skotheim]

I do have some billett k26/27 in stock . With #6 housings . I run k26 from 10v on my s4 . Rebuilt with larger komp wheel , nice for road use .

[Quattronaut]

Sorry for the thread hijack

I have the old Svensk TurboService KX500 26/27 like Sonic. The specs are:

inducer diameter 54.8 mm.
back wheel diameter 76.0 mm.
Compressor trim 72% (0.5 to 1.50 Bar)
Compressor house outside diameter of 170.0 mm.
Single Flow entry turbine.
Turbine Wheel: Exducer diameter 54.5 mm.
turbine: Size 10.0 cm2. (No 8)

The compressor wheel is old school and could really do to be a billet item with a modern design.

http://i.imgur.com/fNbiBS6.jpg

When Albert was supplying 26/27's he suggested something like a billet item IN 56mm, EX 78mm, TIP 81mm would fit.

Any suggestions for this hybrid and where I might source parts??

If the svensk compressor is KKK (don´t know the company and what they work with): should be the "3072 "G". Flow up to 0,350m³/s air, enough for ~460hp. The turbine seems to be normal K26 one. I don´t understand that "10cm²/Nr 8" thing. A "8" hotside has got 8cm², and a "8" is embossed the turbine entry, a "10" housing is with 10cm² and the "10" embossed there. Both match the compressor somehow, the 8 is for better spool with bit less peak power, the 10 would give more peak with little more lag and later spool.

Sorry, I don´t know Alberts wheels, I don´t know any of the own- built and own-distributed wheels from this forum or somewhere else, I just know a little about some single KKK wheels.

[K Simmonds]

Sorry for the thread hijack

I have the old Svensk TurboService KX500 26/27 like Sonic. The specs are:

inducer diameter 54.8 mm.
back wheel diameter 76.0 mm.
Compressor trim 72% (0.5 to 1.50 Bar)
Compressor house outside diameter of 170.0 mm.
Single Flow entry turbine.
Turbine Wheel: Exducer diameter 54.5 mm.
turbine: Size 10.0 cm2. (No 8)

The compressor wheel is old school and could really do to be a billet item with a modern design.

http://i.imgur.com/fNbiBS6.jpg

When Albert was supplying 26/27's he suggested something like a billet item IN 56mm, EX 78mm, TIP 81mm would fit.

Any suggestions for this hybrid and where I might source parts??

No worries on posting up the details of your turbo on this thread Steve, hardly a hijack, I was hoping this would turn in to a useful discussion on K26/7's and their capability's.

I'm yet to start 'shopping' for the 3071 O wheel but there's a few vendors selling billet wheels on-line, here's the first one that pop's up on a google search, they seem to sell pretty much everything turbo related and have a baffling array of billet wheels available.

http://www.turborebuild.co.uk/shop/s...hbutton=Search

[SteveH]

If the svensk compressor is KKK (don´t know the company and what they work with): should be the "3072 "G". Flow up to 0,350m³/s air, enough for ~460hp. The turbine seems to be normal K26 one. I don´t understand that "10cm²/Nr 8" thing. A "8" hotside has got 8cm², and a "8" is embossed the turbine entry, a "10" housing is with 10cm² and the "10" embossed there. Both match the compressor somehow, the 8 is for better spool with bit less peak power, the 10 would give more peak with little more lag and later spool.

Sorry, I don´t know Alberts wheels, I don´t know any of the own- built and own-distributed wheels from this forum or somewhere else, I just know a little about some single KKK wheels.

Thanks for the reply. Definitely a No8 hotside as I've seen the stamp on it, so I think their description of 10cm2 must have been incorrect. The compressor backplate has 5327-5785 075.6/13 k etched onto it too.

[SteveH]

No worries on posting up the details of your turbo on this thread Steve, hardly a hijack, I was hoping this would turn in to a useful discussion on K26/7's and their capability's.

I'm yet to start 'shopping' for the 3071 O wheel but there's a few vendors selling billet wheels on-line, here's the first one that pop's up on a google search, they seem to sell pretty much everything turbo related and have a baffling array of billet wheels available.

http://www.turborebuild.co.uk/shop/s...hbutton=Search

Great link, cheers

[Quattronaut]

Thanks for the reply. Definitely a No8 hotside as I've seen the stamp on it, so I think their description of 10cm2 must have been incorrect. The compressor backplate has has 5327-5785 075.6/13 k etched onto it too.

That´s sad. OE "10" hotside housings from KKK were only produced as prototype series in the 90s, and AFAIK MTM bought the complete bunch and used it for some really big K26/27 hybrids. TTE in Germany revived these again a few months ago, so you can order them now again, but you don´t wanna know, what they call up for them...
But the "8" ones are still rare and great stuff. Take care of it

[twoqu]

It does seem that the KX500 was basically a MTM 428PS replica! Essentially the 3072 Comp wheel with the larger K26 turbine and #8 housing which apart from the centre housing was all Porsche based. The compressor side from the 7200 911 and the turbine shaft/housing from the 944T 250 bhp version.
There appears to be both Turbonetic and presumably KKK #10 housings. The KKK one appears to have a rectangular entry rather than the familiar to us round one.
Whilst not wishing to put a downer on this project, the problem is going to be who you are going to trust to do the machining of the compressor cover/backplate to match whatever wheel you are going to choose, apart from the balancing issues and the precise measurements needed to assemble and even attach the comp wheel to the shaft.
Having said that even you you bought a turbo with a warranty and it went pop, undoubedly they would blame you for its demise anyway!

[SteveH]

It does seem that the KX500 was basically a MTM 428PS replica! Essentially the 3072 Comp wheel with the larger K26 turbine and #8 housing which apart from the centre housing was all Porsche based. The compressor side from the 7200 911 and the turbine shaft/housing from the 944T 250 bhp version.
There appears to be both Turbonetic and presumably KKK #10 housings. The KKK one appears to have a rectangular entry rather than the familiar to us round one.
Whilst not wishing to put a downer on this project, the problem is going to be who you are going to trust to do the machining of the compressor cover/backplate to match whatever wheel you are going to choose, apart from the balancing issues and the precise measurements needed to assemble and even attach the comp wheel to the shaft.
Having said that even you you bought a turbo with a warranty and it went pop, undoubedly they would blame you for its demise anyway!

Hey Robin, I though this thread would be up your street! I'd agree, the more I've looked into this turbo, it does appear to be a Porsche-based item. I have no idea who to trust with matching a new wheel to the housing and undertaking the machining AET, Turbo Dynamics, Owen, Craig at TDI, etc....