It's less work and less money to get a 20b to run turbo'd than setup a whole N/A 20b. It involves rebuilding the motor with different rotors, custom manifolds, replumbing just about everything. Why bother if you're going to eventually go turbo anyways. What I did is just start out with the motor and get it running good with the twins before going all out. When you get it running good and all the bugs fixed with the stock motor, then you can start going big.
I see too many people dump tons of cash into a big project either to find out they didn't have too or that they still can't get the thing to run right after hours of tuning. I don't know the exact percentages, but most projects get scrapped before they even start.
If you do go through with the swap, think about how much money you think you're going to spend and then triple it. Thats how much you should have in your bank before you even pull so much as a spark plug wire off your existing motor.
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