XE282S in my 408??? Big enough or bigger?

Latest thoughts are use the XE282S with 1.6 rockers. Swap to 3.23 gears and not sure on stall. 2800ish??? Or will that not be enough. I know the 3800 behind my 340 acts well, but that is a 7500 RPM engine and has 3.91s. The 408 wont see more than 6000