How to tell if T28 is ball bearing or not

COPY PASTING FROM POST I MADE ON ZILVIA.NET

NEED HELP FIGURING THIS OUT…

caps over.

Sooooo…

not all S14 turbo’s are ball-bearing
not all S15 turbo’s are ball bearing

how does one tell if the turbo is ball bearing or not?

are there physical differences? and if so what are they?

currently this is not easy to figure out, but this should eventually be as well documented as the 300z brake caliper info because as it stands alot of people cant even get that right.

i cant imagine how many people out there bought S14 and S15 turbo’s thinking that that are BB when they actually are not.

this is the info i have so far, the part numbers are different on the BB and non-BB turbo’s.

Turbo
Jap PS13: 14411-50F00 (non BB)

AU/NZ S14/CS14: 14411-75F00 (non BB?)

Jap S14: 14411-69F00 (non BB?)
Jap CS14: 14411-82F01 (BB?)
Jap Autech/NISMO 270R: 14411-RP801 (BB, same turbo as early S15 MT but different part no)

Jap/NZ S15 early: 14411-91F00 MT (BB) and 14411-69F00 AT (non BB?, same as Jap S14)
Jap/NZ/Au S15 late: 14411-75F00 (non BB?, same as NZ S14 and same for both Auto and manual)

above info was copy and pasted from an australian site where a nissan employee got the part numbers at the dealership there and another guy did some diggin with some guys in the know. he was unsure if the [ Jap CS14: 14411-82F01 (BB?) ] was BB or not hence the (BB?)

link is:

http://www.nissansilvia.co.nz/phpBB...der=asc&start=0

from this info is it logical to assume that zenki T28’s are non-bb and kouki T28’s are BB? and that late 1998 to early 2000 S15’s are BB but 10/2000+ S15’s are non-bb.

i would also assume that in order for the T28 to be ball bearing the second part of the part number would need to read one of 3 of the following:

82F01
RP801
91F00

this one might also be BB - 69F00

all part numbers start with 14411-

it also looks as though almost half of the the T28 (S14 AND S15) are NOT ball bearing.

this needs to be clarified so that we can determine which turbo’s are BB and which are not.

some more stuff i am finding:

“5 hex bolts on the exhaust side for a ball bearing.”

"The BB aspect of the turbo is not determined by how many bolts hold the dum pipe on, it is determined by how many bolt hold the turbine housing to the core of the turbo.

If there is 6 then its BB.

If there is 4 then is NOT BB."

all unconfirmed

spin the exhaust and the inlet in opposite directions…if it works…they are ball bearing…if they are a fixed shaft and only rotate in harmony then they are non ball bearing…prolly the easiest way to figure that out…im guessing???

what if i were buying them internationally and couldnt get them in my hands.

i would need to go by pics and or part numbers i guess.

with Z calipers there are difference that you can detect by a photo to tell what year they are etc.

there should be subtle differences for the turbo’s that would be equally telling.

we need to do a side by side.

haha that doenst work buds, BB or not the shaft is solid, otherwise the exhaust would just spin faster than the compressor all day long and it wouldn’t work!

ball bearing just refers to the bearing the shaft rotates on, either oil lubricated like engine main bearings, or oil lubricated ball bearings (which have less drag obviously)

I’m really not sure how you’d tell the type of bearing of a turbo, i guess you could take it apart and you’d quickly see

Bing, I have a S14 BB and SpecR S15 inconel turbine with the WG cast divider.

On the compressor side, there should be a discription after the GARRETT wording.

S14 - A/R60 M24 1-1
S15 - A/R60 M24 1-2

vince, take a few solid side by side shots of them…