ok so i got a used Greddy turbo kit for my d15b. it came with everything including intercooler ect. now i have been reading and that "elbow" that greddy uses to connect to the downpipe just robs power....can i use a 5 bolt downpipe from like ebay on it? its a 15G turbo(small

) what bolt pattern would i need?
actually i think its a 4 bolt