Man! You really need to make up your mind and stick to it once and for all, DOHC, DOHC, SOHC and now DOHC!
Ok, here's the deal:
- You'll need to swap in the complete wiring harness and ecu from a twin-cam G13B.
- You still wont be able to rev it as hard as a stock twin-cam G13B (im thinking 6.5K at the most) since the bottom end from a 1.5/1.6 G-series isnt as strong. (The G13B came with forged connecting rods)
- The head would only do you good upto 6-7 psi boost after that you'd need to reprogram the ecu for sure to accomodate the vast diff in ignition & fuel maps due to the flow characteristics of the wide-angle head.
- The oil pump would probabaly need rebuilding as well.
- You'd need to get a new belt.
- Fabricating a custom timing belt cover would be required.
- People have done this swap before but not really sure if they gave any attention to the slight diff in bore. G15A bore=75mm, G13B bore=74mm
All in all, do you really think it'd make a diff if you couldnt really utilize the extra revs the head was designed for? It'd be a diff story all together had you opted for the G13B DOHC motor itself and built on that. Much stronger internals!
