you could see nearly 400 with a 34/63 and a set of 55lb blacks and a easy 340 on greens with the right chip

i use MSD chips and although my lumps done 110k still produces 332 bhp on a std lump with a T34/48 my m8 done 347bhp with the same spec turbo and greens

Get the chip checked before you use it you could damage your fresh engine

Hope this helps

Paul