Can I convert manifolded doubles to sidemount?

[gathan]

This is what I did; split up my worthington HP100s and fiited dive rite left and right hand valves on them. The cylinders trim great.

 

[Dive-aholic]

I guess / assume that the best cylinder size has something to do with the position of the cylinder base in relation to the knee and the cylinder weight, and not the width...
I just don't know.

No, it doesn't have anything to do with the base in relation to the knee. It is dependent on the buoyancy characteristics and the distribution of the weight along the cylinder. IMO, Faber 95s are great sidemount cylinders, as long as you don't let the pressure get much less than 1800psi/122bar (keep in mind I get cave fills). Any lower than that and the bottom starts to get too positive. However, Worthington 95s are heavy cylinders and require a lot of air in your wing to counteract the negative buoyancy. Worthington 85s are also great SM cylinders, but Faber 85s start to get positive at higher pressures. Worthington HP100s are also great cylinders, but ASAHI HP100s are very bottom heavy and require a lot of trim weight. Again, not all cylinders are created equal.