This is getting very interesting....Love it! This motor I built is from a 310GX(us version so this was badged as 310GX and was front wheel drive)and really all that was retained was the short block. The head is a true GX head from an unknown origin, meaning I got it while swapping parts and can't figure out what it really is other than it has dual valve springs and oval ports, water jacket ,and dual SU manifold and carbs came with it. Also have GX header(I was told anyhow by a few 1200 nuts that I showed it too at the time)It is shorter than the headers that dimlight65 posted pics of.There is a head pipe that came with it with a three bolt flange and two to one collector.Btw..when I was comparing motor parts to the a14 it seems like the rods were the same but the pistons had the wrist pins in different places to achieve the shorter length with the longer stroke. Actually this is fitted into the a14 block as it was in better shape after sitting around waiting for me to put the parts together. Both blocks measured the same deck height. A 1200 racer told me he used the A12A since it pulled harder out of the corners so this was my thinking in using the A15. Sorry for the long post but I've been the lone 1200 here for too long and it gets lonely