i am about to recieve a .42/.48 t3, i want to have a little more top end so i was thnking about making it a .42/.63 with a .63 comp housing
will this be effective or do i need a bigger compressor whell too??

 

you need the wheel too

 

just the housing and wheel??
does the manufacturer of the turbo matter? ie: i have a garrett can i use a turbonetics housing and wheel




edite:
now i'm getting confused.......again

when talking about a/r 42/48, .42 is exhaust and .48 is compressor, right?

 

Usually .48 is the exhaust and .42 is the compressor.
And 63 is the exhaust and .60 is the compressor.

 

Im sorry I cant give you exact numbers but I can confirm Hybrid turbos when they work will blow your socks off.

This is what we did. Got a IHI RFB5 VI35. Hooked it up no boost till 6000 RPM.
Went to the junk yard and found the tinyiest little IHI RFB5 turbo we could find which turned out to be VI21 striped the exhaust housing off it. Tried to put it onto our turbo. The housing hole was so small the exhaust side blades where not even able to get in. We machined the ---- outa that exhaust housing. Till we got it over the Exhaust hosuing.
Now it has instant boost. It dosent feel scarry cause you have presure from the minute the engine starts. It hits max boost by 3000 RPM at which time the waste gate opens. If we disconect the waste gate we have hit upto 20 PSI at 5500 RPM.

If your going to swap ex. housing it will have to be off the same familly of turbos. Otherwise the bolt paterns wont line up.

 

makes more sense now. i would end up with a .60/.48

what would happen if i only swapped the comp housing and not the wheel with it

 

THere's not much you can do to make it spool up quicker

0.48 is the smallest turbine. Well, they make a 0.36 but that's too small for any serious power.
The 0.48 a/r turbine will spool up acceptably fast with as few as 100 HP before boost.

Compressor wise, Just select one that is the smallest possible while still able to reach your HP goals in his max efficiency zone.

For example, if you are looking at 200-250 HP, your t3, assuming it's a 50 trim, as it is, will be perfect.

if the t3 48/42 is spooling too slow, then you should IMO go with a T25, T28 or RHB5

 

i'm pretty sure the .42/.48 will spool just fine by looking at other dyno's. but i want to hit ~225 on my stock A6
and it looks to be a bit small to hit that mark on a stock MAP sensor. i know i'll still be pushing it but it seems to be a little more feasible with a .60 comp housing

 

cahnge the comp housing and comp wheel..you need the comp wheel..
and Turbonetics turbo's are Garrett type turbo's it will swap no problem....
I have a .36 housing on my T3/T4E 57 trim Spools really fast, but the boost does drop a bit at higher rpm's...
I got full boost at 3200 rpm's holds it to 6500 and after that boost drops with 1-2 psi..
It's on a ZC revlimiter at 7400rpm

 

Yeah! Semnos, AHAHAH!!! That's what I would expect from a 0.36 a/r turbine!! It is TINY!!! THe choke on this tubirne is so small, it doesn't take much HP for it to become an obstacle to power!

Racintweek, for 225HP, assuming your 0.42 a/r comp is a 50 trim, you cn give it a try. It will over heat more than a 60 trim t3 at this HP level but it would work... with an even quicker spool up.