Alright...one would look at a compressor map to determine whether or not a particular turbo is going to give them the airflow they need at a desired pressure, but how do you figure out if the turbine wheel or housing is holding you back?

For example, how do you figure out if you should step up from a t3/t4 to a straight t4?

So, if someone can point me in the direction of this knowledge, I would appreciate it

 

So, does anyone have info on choosing a turbine size/housing size?

 

It's all about the maximum HP you want to make and the spool up desired.

Most people choose a turbine just by getting information from other users, and their own predicted goals.

This is what i use (that doesn't mean its correct):

.48 - 300hp and under (street/occasional drags)
.63 - 300-500 (built street cars/serious drag racing)
.82 or T4 - 500-600+ (all out street car/Drag only)

Of course spool up will depend on engine, bore, CR, Manifold design ect. This is why it's best to ask people that have the same(or close to it) setup that your looking into already.

 

So, the turbine size/style doesn't matter?! I'm looking at a .64 a/r turbine housing, but there are t25's/t3's and probably even t4's with that a/r...so, there has to be another variable...

 

So, does anyone put any thought into what turbine wheel/housing they use? Or, should I just ask what's the best turbo kit for my car?

 

I have been pondering the same question and legendboy and I have come to the conclusion that for me, the .48 housing was too small and too restrictive for my h22a1. So I'm looking for a .63 turbin housing now. With the .48, I would get good power until vtec or around that range and then it felt as if the power band just flattened out. Legendboy contacted garrett and they said that the wheel on the .48 was the exact same as the .63, only difference was the bigger housing. On a civic I think the .48 would be a good size cuz I installed a t3/t4 in a friend's d16z6 and his car picks up at the end. It takes a while to spool but when it does, it really goes. which reminds me, does anyone have a .63 t3 turbine housing they want to get rid of?

 

Make sure the .63 turbine you find is designed for a stage 1 wheel. If it's designed for a stage 3, it will not fit correctly.

Ion:

Many turbine's have the same "AR" because all it is a ratio. I can't remember what exactly is accounted for in that ratio. This is why many small and big housings can have close AR's.

just like

6/3 = 2
8/4 = 2

same thing.

What style of turbine are you looking for? you can't just say I'm looking for a ".64" turbine.

Most people utilize the T3 turbine as it can flow enough for 500+hp, yet spool up very fast on most honda engines.

What is your:

Engine
Goals
spool up desired
?

These are the questions that will help decide what turbine to choose.