Need some input guys. I am currently running a mud bog truck in a class that requires you to pull 16" of manifold vacuum at 1000 rpms.I changed cams a couple of weeks ago and now pull 17".I have worked vortec heads with 1.5 rockers. Will changing to 1.6 roller rockers increase hp and tq? Will this affect vacuum?  

It's awfully certain that it will increase power, as it should increase lift by approximately .030", increase duration at .050" by 2-3°, and increase valve acceleration throughout the lift 'cycle.'

It's a little more uncertain that it will affect vacuum. Theoretically, it should decrease it slightly as it increases the amount of time both valves are open simultaneously (overlap 'triangle area'), but this may be nearly insignificant with only a tenth of a ratio. Increasing the rocker ratio on the intake side would also be beneficial here as most likely the exhaust doesn't need the extra help as much as the intake. The gains from added ratio to the exhaust valve depend on how far you are revving past peak power, as the gains can become significant here.  

What about switching to rollers? Staying in power band with peak revs at 5300 on sb 400. Truck runs great as is just looking for any possible gains.  

At 5300 rpm the more significant gain will be from upping the rocker ratio, not switching to a roller. I would guess that the roller rocker itself would be 4-5 horsepower.  

Thanks for the help GibTG think I will give it a try.Maybe it want effect vac and give me a little extra power.  

I think that is the best course of action here, just try it! I highly, highly doubt your vacuum will drop more than 1" Hg and if it does, just switch back to your old rockers.