bebolagalas,
hehe, i've read from the US forums, generally loads of US people r very knowledgeable in their car mod, just send ur TD04 to Turbo One and tell them u want to upgrade the compressor fin, might as well do the service at the same time, Turbo One will port the compressor housing a lil to make clearance for the bigger compressor fin, i only upgrade from 13G to 15G, a TD04-15G is almost and very near the same power produced by TD05-14, it's a good option considering there's practically no lag at all.....
but u need to do some research for ur own engine, different engine different requirement, and even same engine but different mod bears different requirement too, pls check the info below for max CFM flow :
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