Turbo Impeller Clearance

[Sowler]

I have few questions regarding turbos which are one my turbo CRX, I am no expert and I've tried googleing the answer to no avail.

I have two turbos. One was bought as supposedly as a ' Garrett Super 60' whether it is or not I have no idea. The other was an eBay special T3/T04E (I think)

Now the A/R specs of both turbos (housings?) are as follows:

Garrett
Inlet A/R 42
Exhaust A/R 63

eBay
Inlet A/R 50
Exhaust A/R 63

What the wheel trims are of either, I don't know.

Now I would really like to use the Garrett turbo as the spool on the eBay one is a little late for my likings and I am hoping, the smaller A/R of the Garrett will help this. However the clearance around the exhaust impellor on the Garrett seems rather large to me? But I am no expert. Thoughts.





eBay



Garrett



Regarding only one housing, the eBay one came with a 5 bolt exhaust housing, still a A/R 63 it fits exactly the same clearance wise etc as the 4 bolt one that came with the Garrett and my down pipe is 4 bolt. As you can see the Garrett is a little gapy IMO but whether this is a problem I don't know. The screwdriver is just gently placed in there as a size reference.

John

[Sowler]

stevieturbo said:

So you're trying to fit a turbine housing to a turbo core/turbine wheel it was never intended for ?

And as you see it does not fit correctly ?

The Garrett came (to me second hand) with the housing you see me putting on it! Ie the one with loads of gap.

Boosted LS1 said:

The blades should be as close to the housing as possible but not touching, otherwise air flow will most likely be crap. Imagine if your water pump had a massive clearance around the blades.

Yes I understand this, however what I don't know is what should the clearances be and what is normal.