Adam had a twin system from Pius at Bell Turbo that could not be fit in the over under config. He got it in using the alternative inboard/outboard installation. The turbos are getting so large that installation is becoming difficult.
The pic is of my first sys years ago when EE first began to do twins. In this inboard/outboard sys you could run a larger low pressure turbo.
The pic is of my first sys years ago when EE first began to do twins. In this inboard/outboard sys you could run a larger low pressure turbo.