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Can Someone Confirm This Is A 25det Turbo?

GTS4onP

By GTS4onP,
in Engines & Forced Induction

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GTS4onP Enthusiast

GTS4onP

Posted
Posted

hey, just bought a rb25det turbo and when i compared it to a spare 20det turbo it looks pretty much the same. the only difference I could see was that the compressor housing was twisted around (it was setup for a 180sx top mount)

have added some side by side photos, so hopefully you guys can tell me it is a 25det turbo and not a 20det :)

post-52314-1220139508_thumb.jpg

post-52314-1220139722_thumb.jpg

post-52314-1220139836_thumb.jpg

post-52314-1220140001_thumb.jpg

CEF11E Veteran

CEF11E

Posted
Posted

the numbers have been ground off the compressor housing so visually it's hard to tell.

there is a way to tell. take the elbow off that turbo and see if it bolts onto your rb20 turbo. if it does it is an RB20 turbo. if it dosent it is an rb25 turbo. cheers

Dale FZ1 Veteran

Dale FZ1

Posted
Posted

RB25 doesn't have the pressure feed on the comp housing for wastegate actuation - there shouldn't be a fitting there.

RB25 housing is noticeably (visible to the eye, and measurable) larger in cross section which means it has a larger A/R and flows more.

RB25 compressor impeller is larger in all critical dimensions - inducer and exducer. That means as you look into the throat of the compressor, it will look bigger. Verniers should measure up the throat larger too. If you pull the comp covers off you will see very quickly.

~R33AzzA~ Proficient

~R33AzzA~

Posted
Posted

Looks like an rb20 r32 to me.

As Dale FZ1 said "RB25 doesn't have the pressure feed on the comp housing for wastegate actuation - there shouldn't be a fitting there".

Was it a reputable seller?

GTS4onP Enthusiast

GTS4onP

Posted
  • Author
Posted

ok gay lol, looks like its a rb20det turbo as the turbo elbow bolts up to my spare one

and i bought it off my friend as he was told it was a rb25det turbo

QWK32 Veteran

QWK32

Posted
Posted

don't go off the vacuum line fitting on the compresser housing, when i've put rb25 turbo's onto R32's i've tapped a hole there to bo able to do this, so i'd think that other people would also do this. the two turbo's are almost identical in physical size so the only way to really tell is to pull off the compressor housings off both turbos and compare the compressor wheels, the RB25 one is slighly larger.

or do what CEF11E has said, the RB20 turbo elbow wont bolt onto a RB25 turbo without modification, and even then the flange face on the elbow is smaller than the flange face on the turbo.

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