what is the down side to using 2.75" vs 3" piping on the throttle body side of the intercooler?

Problem is I cant find any local place that can mandrel bend 3" piping.

this is for my soon to be custom AA stage 1 at 8psi

There is no problem to using the 2.75" or even 2.5 " all around.

Just make sure the pipe from turbo to intercooler is 2.5" :)

thanks

Just call www.stainlessworks.net and tell them what you need.
1) 3in 45 degree mandrel bend with a 10in leg on one side and a 3in leg on the other.
1) 90 degree bend
1) 90 degree bend with 6in legs on both sides of the bend.
Thats all you need for the intake side...should cost only about 80.00