No it does not, unless someone put them on it, Not factory on that year.
The impala ss LT1 did not come from the factory with roller rockers, they came with stamped steel rockers. If you are installing roller rockers in yours, the common advise is to go 1/2 turn after 0 lash, when the pushrod no longer moves up and down.
Wikipedia shows the Toyota AR engine with roller rockers started in 2008. This particular engine has many low friction benefits to it.
Yes There is Less Friction More performance, and flat lobes are a thing of the past. Really want to make a difference add roller rockers not aluminum kind but the stainless steel needle bearing rockers . Less wear & tear on valve guides and valve train over all.
It's not really about what rockers you run. If you have guide plates, you need hardened push rods.
No it does not. Unless someone else installed them. Was not factory.
yes
Take off one of the valve covers, if the rocker has a roller tip on the side which it touches the valve spring then its a roller, if no roller tip is present then its a normal tappet rocker.
If you have a 2001 or newer engine, it comes with roller lifters and roller rockers from the factory.
yes, with roller rockers.
Not if you did it right the first time.
They can be ordered with 3/8" or 7/16".
The cast of The Rockers Are Alright - 1994 includes: Roger Daltrey as himself John Entwistle as himself Pete Townshend as himself