I've been trying to figure out a couple things about turbos. I'd really appreciate it if I could get some flame-free responses.

1. What on earth does T3 and T4 mean? Im thinking its the sizes of a turbo? Why are there T3s, T4s, and T3/T4s? Any others?

2. I did a little research on what a wastegate is/does.. it quits boosting the engine at a certain RPM, correct? Where does it bolt on, what does it look like, whats the difference between a 40 and 35 wastegate, is Tial a company that makes them?

3. I've gathered from searching that not all turbo kits allow u to keep your a/c. Is this because of the manifold? Is it a clearance issue?

4. I've seen some manifolds with all these funky curves in them.. is there some advantage to having curvy manifolds?

5. How does a blockgaurd help anything?

6. What does it mean when someone says "I didnt use a cheated downpipe"?

7. What is a/r and trim when referring to a turbo? Im really lost on that.

****, if anyone can help me out with atleast one of these questions, I'd appreciate it. Im trying to learn something.

 

Since its christmas and all. ill awnser you one question.
a wastegate is set by a spring. once you reach a the predetermine ammount of boost it will release exhaust gas out of the wastegate. 35 and 40 mm are the sizes. there are internal and external wastegates. when you look around at peoples set ups you will notice an external wastegate on the manifold. yes tial is a company who makes them.
Happy holidays to all.

 

1. T3 T4 are sizes... a T3/T4 is a T3 turbine (hotside) witha T4 compressor (cold side)

2. already answered.. bolts to turbo manifold... 35/40 is the size of the hole it bolts to, i.e. size of wastegate, bigger lets more exhaust out... they work by having a spring that has say 7 psi of tension, you run a boost referance to it and when your boost hits 7 psi the spring is pushed open letting exhaust go through, which doesnt go through the turbo anymore, so then your boost stops raising.. if boost lowers past the spring rate the wastegate closes and boost rises again

3. yes

4. the theory is to time the exhaust pulses to hit the turbo one after the other in a series without hitting eachother so much in the manifold. a in a honda 2 cylinders fire at a time so with a short log manifold the turbo is being spun by a big rush of air then a wait then a big rush of air when the other 2 fire... it all happens verry quickly though, that is why it still works. The benefit is faster spool time, the downside is cost, and clearance issues

5. your pistons push sideways on the cylinder becuase it is being spun around a circle (crank) when you start making power and spinning the motor fast this force which is called sideloading can break the side of the cylinder/sleeve because it is not reinforced from the factory. a blockguard is suposed to support the cylinder at the top, protecting it from sideloading... the downside is reduced cooling capacity.

6. ????? never heard that ?????

7. a/r is a ratio of the size at the outlet of a turbo and the size where the tunnel hits the compressor... if you look at a turbo as it goes around in a circle it gets bigger.. this is what a/r refers to... if you have a .50 a/r your outlet is twice as big as it is at te compressor... in the hot side it is the same, except the exhaust goes in through the big part and is reduced smaller before it hits the turbine...

Merry Christmas!

 

thanks for the help guys, It wouldnt let me reply to this post earlier.. dunno why. Would you mind posting a pic or two of what your wastegate looks like?

Merry Xmas