Is 8 foot pounds normal for a new HW30S?

659 fps is a bit faster than my 1998 Beeman R7 (HW30) got with Super Domes.

Initially, I got ~582 fps with Super Domes. After a couple of years I installed a Maccari "Steelgate" spring together with some TLC performed on the internals. That increased my average to 615 fps with Super Domes.

Yours is a little faster but it does sound like a reasonable number to me.
 
I'm no expert, but I suspect it's a normal power level for HW30's in general. I bought a .22 HW30 about a year ago. Stock it put out about 7.5 foot pounds with most lead pellets. However, with the H&N alloy 9.56 FTT green, it got about 8.3 foot pounds (624 fps) at the muzzle. With a Vortek spring kit, that jumped to 9.5 foot pounds (672 fps). Amazing! But the FTT greens are quite expensive, so I only bring them out occasionally.
 
These HW30s I have in .177 and .22 have all been way beyond what my only R7 had done (I gave away the R7).

They are the pristine simple machine that all break barrels have. I haven't found better break barrels other than the gas rams by Theoben which I owned all calibers and kept one in .25.

I shot .22 HN FTTs after getting the results from AOA the velocity at the muzzle was 495 fps for those pellets. The target said a "20" yard velocity so I believed the around 500 fps for a relatively heavier .22 type of pellet--no express pellet.

Well! I just shot whatever I had in .22 anywhere through that HW50 .22 and could easily hit small sand pebbles at 25 yards in the open sights shot after shot.

It became my favorite HW30 but I gave it to another who wanted it.

I had the .177 HW30 brand new and also an older vortexed .177 I bought used many years ago because I fell in love with that old rifle right away and got it for what seemed the lowest effort! 

I gave away all my NEW HW30s and kept the really old vortexed one which still has the original spring wrapped inside an airtight bag. The "old" vortexed rifle is the best because it has a set back trigger too and trigger adjustments not as rough as out of the box HWs.

Anyway,

The HW30S whether it creates fps or ft/lbs up or down is really insignificant. THEY work.

The words of an airgunsmith to me were: Chronographs mean zero compared to what an individual wants an airgun for. A few more or less fps doesn't do anything to the accuracy or the hit on the animal.