The bolts that hold the carriers are the same spacing. The spindles that the rockers ride are not. Just because it bolts on doesn’t mean the spindles are the same spacing.
1200
1000
All it takes is a toothpick to compare the centers and you will see, they’re different.
The shorter length pad-side will cause huge lift of intake valve and even more on exhaust valve. Actual true measurements would have to be done with something in the hydraulic actuators to keep them at where they will be when pumped up.
I believe it will be nearly half an inch of lift, much more than 1000/1100.
As per timing, the cams will need to be advanced on the left side to lift at the proper time. (About 2 teeth on the gear as I recall) and retard it on the other side. I could get the left side to have decent compression. I could not find a spot where the right side would clear. As I mentioned with adjustable cam gears it might be made to work. My brain can’t process it all.
They bolt on and turn over like they’re okay, but crank it up, let the adjusters charge and you’ll have contact. As I mentioned, you can get a spot where they’ll all clear, but one or two or four will have low to no compression. The hydraulic rockers block vision of when valves are opening or closing.
The way that might work was hinted at by desertrefugee. The 1500 valks had solid lifters. I don’t think they will work because the valk uses the same arm on both intake and exhaust. The four cylinder Wings had rocker A and rocker B slightly offset between adjusters and pads.
One thing I found odd last summer was the greater exhaust lift. I just went and looked and now know why. The exhaust spindle is closer to the head than the intake spindle.
The 1200 valves are the same length, springs are the same, the difference is in the keepers. You could use the 1200 exhaust valves in the other heads as long as you use the same keepers. I did it.
I looked a bit for other crossover rockers but that’s a needle in a haystack. You would also need custom or crossover springs. It will turn over, but I’m not comfortable with seeing what would happen as they heat up.
