Are the Throttle body from 16vt and 20vt very different? Does the 20vt contain the maf sensor? Was offered a ported 20vt throttle body, but since mine is a 16vt, I'm not sure it will fit?

will not fit... totally different - TPS sensor mountin etc..

better way is to modify stock 16VT - thinned axle+ bolts or overbore up to 60mm..(be aware- needs some welding before machining, because of too thin wall)

I did both on mine 16V NA..

comparison stock vs 60mm(thinned axle)



60mm + thinned axle



stock (sligtly modified)

Thanks Honza! Nice work, by the way!