Originally Posted by Omniscient
You have quite a bit on your plate. A lot to think about. For the money spent rebuilding the d16 to get reliability and power, it would probably make 1/2 the power you would make using the money to swap a bigger motor in and modifying it. Maybe it's not your cup of tea, just an idea to think about. Either way you're going to have to pull the engine out.
Well, obviously your not going to get as much power with a built D over a built B, but parts are a lot more expensive for B series. Also, IMO you will have a lot more fun with a boosted D. Virtually both motors have no torque to begin with and very little whp difference. So that means it really comes down to what your budget for parts is, and if you want to be known as having a DOHC over a SOHC.