Just bought stock evo 8 and am wondering if i fit HKS GT3037S turbo upgrade, what extra horsepower can i expect and if i will suffer any turbo lag? Do I need modifications to computer?

 

Check out RNR, AMS, ATP etc....

 

well you have the dual vane type turbo manifold so, look around on what type of turbo you want, the match a manifold to go with it, now dont forget about the turbo dump (elbow). The clearance is also something to think about. The size of the intercooler is something also, the more you cool the air the better for an upgrade since the compressor section heats up a lot also. The ecu wont really be necessary if youre not going to push above 400. Id say the turbo youre thinking of will prolly be around 300 to 350, not sure on the figures. If youre still thinking about a bigger turbo, make sure that the stock internal, and gaskets can handle the boost... Well I think i said enough. Check to see what everyone else have to say about this, im prolly missing something...