If you can get an orig 1600 L16 bottom end and have full sleeves installed
you should go for a L16 with L18 crank and no pollution gear required.
Full sleeves are 130-160aud each inc bore and honing

modded LD28 or FJ20 conrods 140mm c-c and honda K24 cast 90mm pistons
500-600aud

Factory ka24de head make 150hp yet with restrictive exhaust and cams.
Cleaning up the slags port castings, some match porting you have a head
capable of 180-200hp if 10.5-11 to 1 comp, cams, exhaust, 45-47mm carbs.

Also if getting billet cams you can get the ends after last lobes taken off
they seem to serve no purpose except for timing on fwd ignition pickup sensor.
8500rpm with good valve springs should be no issue with L18 78mm stroke.
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