Since people here LOVE to talk about upgrading to a ko3s and ko4, i thought you guys would like to actually see the size differences. That, and im sick of stating the differences almost monthly

Ko3 - 97-2000

COMPRESSOR WHEEL
Inducer: 33.6mm
Exducer: 46mm
Tip height: 3.7mm

TURBINE WHEEL
Inducer: 45mm
Exducer: 38mm
Tip height: 6.8mm
Blades: 11

Ko3S - 01+

COMPRESSOR WHEEL
Inducer: 38mm
Exducer: 51mm
Tip height: 4.4mm

TURBINE WHEEL
Inducer: 45mm
Exducer: 38mm
Tip height: 6.8mm
Blades: 11

Ko4-015

COMPRESSOR WHEEL
Inducer: 35mm
Exducer: 50mm
Tip height: 3.7mm

TURBINE WHEEL
Inducer: 50mm
Exducer: 42mm
Tip height: 6.4mm
Blades: 11


As you can see and have been told, the ko3s has a larger compressor wheel than both the ko3 and ko4 along with a more effecient design. However, the ko4 has a slightly larger turbine wheel which makes it able to flow the higher power made by chipping better. The best thing to do if you really want to go this route is to buy a ko4 AND used cheap/dead ko3s and swap the compressor wheel and housing to the ko4. This should net you a few more whp and tq

 

You're the mod, make it a sticky

Here's a cool sheet of what engines a K03s came on (by engine code):
http://www.qpeng.com/faqs/engine_faq...they_mean.html

 

Good info. Thanks again cincyTT.

 

This info has now been added to the 1.8t turbo upgrade thread in the sticky above. You can also have people search for this thread if need be.

 

would the inducer be the same as the inlet size?

 

No, the inlet can be tapered down to the inducer size. For instance, a gt30r can come with a 4" inlet but the inducer is a little more than 2"

 

"The best thing to do if you really want to go this route is to buy a ko4 AND used cheap/dead ko3s and swap the compressor wheel and housing to the ko4. This should net you a few more whp and tq"

Isnt this what Gpopshop does with their hybrid Ko4s?

 

Thats what i was thinking. Havent gone searching if that was the case or not. Should be cheaper and make slightly better numbers than a new ko4-015

 

http://www.gpopshop.com/kkkturbos.html thats there info, i don't think they do

 

thanks for the good info!