Hi...I would like to say thanks to synapse.turbo.com ,and credits to Mmailto:Morgan@synapsemotorsport from honda-tech.com who shares this most useful info to us all. The above pictures are the differences between Borg warner S256 and Garrett GT3076. S256 has bigger shaft dimension to withstands the centrifugal force during high RPM. eventhough GT30 has 1mm bigger inducer, how ever s256 has bigger exducer which 85.95mm while GT is 76mm. ETT stand for extanded tip technologies which introduced by Borg warner giving more spooling and compression capabilities, some other people say better than ballbearing. S256 is journaled bearings providing user to rebuild or upgrade to another stage like installing billet impeller or compressor. U might also change to bigger inducer like the one u find on s258 series.
Borg Warner S256: .50 A/R compressor housing Compressor Inducer 56.0mm Compressor Exducer 85.95mm Turbine 75-76mm (odd number of blades couldn’t put a caliper directly on it just a ballpark figure)Turbo with .70 A/R 4 bolt housing: 21 lbs Turbo with .85 A/R 6 bolt housing: 23.2
GarrettGT3076r Compressor Inducer 57.0mm Compressor Exducer 76.14mm Turbine 59.90mmTurbo with .63 A/R 4 bolt housing 15.0 lbs.
i would recommed for u guys to have a look at his forum site becouse he shows both turbo tested on his own vehicle http://honda-tech.com/showthread.php?t=2220363
Now I would like to share mine s256 but non ETT. I brought it on january this year but under certain circumstances I had delay the installation to my engine. In order to fit it in I have to make few changes examples new exhaust magnifold, oil feed line, intercooler piping, radiator fan and down pipe.
this picture shows modified radiator fan. i have cutted at some area near to turbo housing it's a DSM flanged