bingo... we have a weiner
yeah tho your colors are around the wrong way
are you going to use a new pipe to the throttlebody or re-use the factory cross over pipe?...
i am using 2 1/4 piping front turbo, flares up to 3" intercooler inlet exits at 3", tapers down to 2 1/4, joins a step up pipe that is 2.5" then joins the factory cross over pipe.
i dont know any real pro's or con's of my method, but it was suggestted by 2 workshops and my brain... and it works fine for me.
Having said that.. after going flat out for a while, parking the car.. the pipes heat soak abit, but within 40seconds of driving inlet temps are back to 23-25deg