Bill,
I did some math on this a little while back also. I don't know how you got 115lbs, but it sounds right. I did a quick figure and going from a 1.5" bore cylinder to a 1.75" bore at 600PSI would take the cylinder from exerting 1060 lbs to exerting 1443 lbs. So, yeah.... 1/4" makes a BIG difference! Anyway, I was running numbers the other day for this 582D project I'm working on and planning on doing something similar, and I found that even if I ran 2 QL cylinders for the 3PT it wouldn't exert the same pressure as 1 '82 series cylinder. Now, we both know you can do a lot with leverage, after all, I'm not sure there is much lifting difference between the QL's and the '82 series, they just used a longer arm with the smaller bore cylinder. In all the research I've done, it seems all the GT manufacturers used that cylinder off the '82 series in their tractors. (JD, Bolens, CCC even some of Jacobson and Ransomes) So finding a cylinder bigger than that will be tough. Finding one between the two..... I haven't yet. So, I think the best bet (and my plan) is to try and use either 2 QL cylinders, or 1 '82 series. You just have to adjust the rockshaft arm that attaches to the cylinder to compensate for the bore and stroke difference. Or, you could go to a hydraulic shop and have them make you a cylinder......
I have a shop that does that. It's not as bad as you might think ($$$ wise). But still will be FAR more than using one already in production. Just my
