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emoore924 · Joined: 13 Apr 2004 Posts: 2822

Like the subject says...

What does the 4.10, etc. mean exactly in the K26 turbo specification number?

steeny · Posted: Fri Feb 23, 2007 9:38 am Post subject:

have you tried looking in the thread directly below this one? i think its titled : all the k26 stuff you could ever want to know

cheers
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1978 924 N/A
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flosho · Posted: Fri Feb 23, 2007 1:18 pm Post subject:

"R" - still unsure about this...
"6.10" refers to the turbine wheel, there's no rhyme or reason with KKK's numbering system here. For example a 5.10 could be larger than a 6.10 which could be larger than a 4.10. Stupid engineers...

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emoore924 · Joined: 13 Apr 2004 Posts: 2822

Steeny, you might notice that I've contributed to that thread on several occasions, so I've seen the content there. Unfortunately, the thread you reference DOES NOT address my question. What does 4.10, etc., mean *exactly*. Does 4.10 mean a 55mm turbine wheel or a 48? Does 6.10 mean a 52? I want to know what size turbine wheel is installed on a K26 with a 4.10, 6.10 or 8.10 designation, not just that they're different or that the numbers aren't relative...

I intend to add the facts to the other thread once they become known, rather than clutter it up with investigative discussion.

462avi · Posted: Sat Feb 24, 2007 1:41 pm Post subject:

Emoore924

That might be a good question to ask the companies that rebuild these turbos. Maybe they can assemble any size turbine/compressor combo we want. I think we should contact that company in seattle and see if they have any info on the turbos we have.

Geoff
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2002 grand cherokee with 4.7L

Tigger937 · Posted: Sun Mar 04, 2007 4:09 pm Post subject:

You might also check with Charlie at Evergreen Turbo in FL as he rebuilds many of the KKK units.
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1981 931 (Concours)
1982 931 (Daily Driver)

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gegge · Joined: 27 Jul 2007 Posts: 1124 Location: Sweden

I found three explainations, but I am not sure which is correct:

"The #4, 6, 8 and 10 numbers reflect the turbine scroll volume in cubic centimeters, the bigger the better for higher exhaust gas flow and thus HP but very big also means slow spool-up and lag."

"8cm^2 is referring to exhaust discharge area in the turbine housing. More specifically, it is the smallest cross-sectional area of the scroll, turbine housing. Very similar to Garrett turbo's A/R. The smaller number means faster spool-up but more back pressure at higher rpm. Bigger number means longer spool up but less back pressure, thus more top end power."

"Looking through KKK tech papers this number is the A/R of the housing. So a K27 9.11 housing with a 9 stamped on the inside of the housing is a .9 A/R"

I was told that the number after K26 is turbine nozzle area in cm2?
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Carl Fredrik Torkildsen

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