AGreen

iTrader: (11)

Where can I find specs for rebuilding turbochargers? Specifically the stock one, but is there some sort of database for all (or most)?

By specs, I mean stuff like clearances, torque values, runouts, etc. Not trim, A/R, etc.

I was fiddling around with an old turbine shaft piston ring seal and a bearing housing, and decided that I'd see how much gap there was. So just like when rebuilding a piston engine, you have to gap the rings by putting them in the cylinders one at a time and measure the ring gap with a feeler gauge. I found that the turbine ring seal had about .004" of gap. That's great, but with no spec to compare it to I have no clue if it's good or not.

ScorpionT

iTrader: (3)

What kind of turbo?

Distributors and rebuilders should have this information. It all comes from the manufacturer.

AGreen

iTrader: (11)

I have a S5/TO4B hybrid, so everything should be the same since it's only the TO4B compressor on it. The only difference is that it has a 360 thrust bearing and dynamic compressor seal.

rxspeed7

iTrader: (5)

im also curious on this, i would def like to know what the clearance between the wheels and housings are.

ScorpionT

iTrader: (3)

Thats something you would need to go to the builder for. Manufacturer specs will be different from a custom unit.

For example, if you have a Garrett GT35R and you send it to Precision for a billet compressor, they have their own specs for clearance between the wheel and housing.

AGreen

iTrader: (11)

I don't know who built it. I bought it used from someone who didn't know who made it either. Possibly a panspeed or knightsports was what he said, but nobody really knows.

I found something from GPopShop. They apparently gave me a "how-to" sheet for rebuilding a garrett T3. I found it while rummaging through some of my stuff today.

Compressor Wheel
- Bore diameter .2498 - .2501
Backplate
- Piston ring bore diameter .4995 - .5005
Bearing Housing
- Bearing bore diameter .6220 - .6223
- Piston ring bore diameter .709 - .711
Turbine Wheel
-Journal Diameter .3997 - .4000
-Seal hub diameter .679 - .684
-Piston ring groove diameter .567 - .572
-Piston ring groove width .0645 - .0685
-Eccentricity .0005
Thrust Collar
-Bore diameter .2501 .2505
-Thrust bearing groove width .1740 - .1748
-Thrust bearing groove diamter .370 - .380
-Piston ring groove width .638 - .653
-Piston ring groove diamter .405 - .410
Clearance
-Radial bearing clearance .0030 - .0065
-Axial end play .0005 - .0040
Bolt torque specs
-Backplate 75 - 90 in/lbs
-Turbine housing 164 - 181 in/lbs
-Compressor housing 145- 165 in/lbs
-Shaft nut 28 in/lbs + 90 degrees



That's straight from GPopShop for the T3/T4 rebuild kit. I don't have anything for the piston ring gap, but I guess if the bore diameter and piston ring groove diameter fall within spec, then the ring won't allow any leakage.