L series would be great for outright power and striaght lines in most cases but from our Datsun runs, i always see the Boof mobile way way ahead of the L series magic of the Pigdog mobile (when it was on 4 cyl

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I have and still am considering an L16 conversion just due to availability of lseries parts over a15 parts but my a15 has heaps of live and fun left in it for my tight a$$ budget at the moment.
All depends on what other mods you plan on for the car to handle the power plant, brakes, suspension diff etc.