I rode 27" on one bike for over 30 years. When I found a such-a-deal on the right set of 700c wheels, it opened up a new world of tires and changed the nature of the bike.
Have to agree the Paselas are currently the single best choice in 27" but they run best at high pressure and all you gain is bad handling by lowering the pressure. They're 66 tpi, which is kind of burlap casings.
Better tires (only in 700c) are 100-320 tpi (linen). They spread the heat and the shock better through the tire carcass, and roll efficiently over a wider pressure range.
you're going to need to lower your brake pads by about half-a-centimeter to fit 700c - just check to make sure you can do it.
(they also make some offset pad holders, but I wouldn't recommend it, because lengthening your calipers is making them squishier.
Last edited by bulldog1935; 07-24-16 at 03:34 PM.