I'm planning my rebuild for late summer, and i'm still in the stage of deciding which direction to go... I have to send my irons out to be lapped, an I dont think i want to try the porting myself.

I have an s4 TII block, and I like the idea of a half bridge.

I am thinking... A nicely sized turbo- like a t66?

How do you think this would run at about 10psi?

Just looking for opinions and ideas. Oh btw i'm going to run water injection, just because i'm excited to try it.

 

If your doing something like half bridge and t66 then why are you going for such a low boost level?

 

bigger turbos flow more efficiently, even at low boost levels because of the increased volume...

Is that too big? I asked for what you think about the setup and what you think i should change.

Besides, maybe i'll want more boost later, or to turn it up for races and such.

 

Not for all cases, you have to check compressor maps for efficiency islands. (If you did check, disregard this statement )


If your going to port, better off porting before lapping.

 

Yes, a bigger turbo will flow more then a smaller turbo, however you need to take efficiency into account.

a T66 at 10psi is being lugged around....its not even cresting the bottom of its effciency range.

What are you using the car for?

 

Its NOT a daily, but I plan to drive it in town occasionally. I guess i should look for quick boost because i'm going to autocross as well.

I suppose i need to learn alot more about turbos before trying to decide which one to go with... compressor maps are pretty confusing to me.

That's why i'm here though, I cant even figure out how to use a turbo calculator!

 

want to learn how to read a compressor map and choose the right turbo? Check out maximum boost by corky bell. Should be a must read for anyone lookin gto turbocharge any car.


BC