the compressor wheel is bigger on the gt 3037. i think the a ka24det will take a while to spool the 3037, the 2835 i think spools up a little quicker.. if im correct the hks s-15 silvia uses the gt30 on its drift silvia..
now wastegates and bov are two different things.. the bov protect against compressor surge.. so it vent the gasses into the atmosphere.. a internal wastegate dumps out the excess exhaust gass when the throttle plate is closed i believe.. so you cannot have one or the other get both!
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