and on a 4 cylinder engine it would be that much more expensive to do........not worth the money for the overall outcome......unless you want to do it to stand out........then it could be worth it to you
Actually, the twin turbo cars run two same sized turbo's, just vacuum pressure for one to spool earlier in the RPM range... hence, "twin" turbo. Bi-Turbo like on some Audi's use two different sized turbos...
I think the greddy Profec-B will allow you to set two sepcific boost settings for different gears, for example, 5 PSI @ launch, and then 15 once you hit second gear or something.
Just a thought, cheaper than a TT setup.
What you described is called "sequential turbos". Two differents size turbo; 1 small to get boost faster and to prevent the long lag of the bigger turbo and 1 bigger to boost on top-end at high exhaust flow. Supercharger can also replace the small turbo... some setup have SC and turbo working sequantially.
Something like on the Z or the GT-R TT is not sequential. Both turbos are the same size and they boost half of the engine on their own.