I bought a CX racing Fmic piping kit for a MKIV supra to use with my precision fmic.
The kit has 3" piping all around except for the 2.5" pipe that connects to the turbo. They gave me 3" hose with 2.75" couplings to fit the 2.5" piping (pipe 1), 3" hose for the 2.5" to 3" & 3" & 2.75" couplings (pipe 1 to pipe2), & 3" couplings for the 2.75" inlet/outlet.

As i tried to tighten the 2.75" coupling to the 2.5" pipe with the 3" hose the pipe is super loose.

Is this correct? they said they sold many kits with the same pieces with no complaints about the coupling and hose sizes.

 

I moved the thread here. I believe you will get more hits for the question you are seeking.

 

You will need a 3" to 2.5" reducer coupling.

 

thats what im telling them.
eyesoarer was a name i used in another website....haha!

 

What engine and what turbo? For the 1JZ you need 2.75" to the throttle body and 2.25" to the turbo. I'm not sure with the 2JZ, cuz it's been a while. You'll just have to order the correct silicone coupler.