Question
 

does anyone know the measurements for the coupling that attaches the Greddy aluminum S pipe to the inlet on the stock intercooler?

http://www.hosetechniques.com/catalog_search.tpl

2.75"

thanks but do you know what the lengh is?

AFAIK, they're all pretty standard length...3" inches. I had to cut btwn 1/4 to 1/2 inch off, I just "eye-balled it". Otherwise the coupler will push out against the lower bend and leave it too close to the crank pulley. Cutting will leave some frayed threads, but they can be trimmed with sharp scissors and you can't tell. :)
I used these:
http://hightempsilicone.com/product/HTS2754T3RD

thanks alot for the info. theres a hi performance tuning shop near me and they sell silicone couplings by the length and ive used those for the y pipe to crossover and crossover to s pipe and have worked great for the 5 or 6 months i have had them so i;ll just one more from there