Question: 1 :Inline 5 pot 2.5tdi volvo v70...audi/vw engine 98 plated, as i understand it so far a turbo has to spin up to speed before it kicks in, is the ratio between turbine and compressor the same, 1/1 or is that a variable,2: could i have two turbos of different size on one pipe, a small one that kicks in at low revs and a bigger one to take over on the higher rev band???