Not sure why he keeps saying "can bore to 4.250" 4.20 is max on the block, a 4.250 bore will leave only .105 between cylinder bores......Not good even for siames blocks....... bottom end of the block is thicker where the Main studs go in no "shelf" tpe casting... still only two in the cap and two cross bolts....the ONLY 6bolt G3 (4 cap ,2 cross) were the Mclaren Alum block for the ill fated 5.0 liter program in 04-06 ...

There are some big advantage with this block
1) it has two extra Head bolts , per cylinder one @ 12 o'clock and one @ 6 o'clock. Like some of the Aftermarket LS blocks........ it's a true 6 head bolts per cylinder can you say 30+lbs of BOOST
2) the Water Jacket it's more like the BGE/Hellcat and less like the Eagle 5.7 and the 5.7/6.1 block.
3) the Lifter oil galleys(passages) connect all 8 on the same bank...the OEM blocks are split in to 4 sections of 4.
4) unlike the BGE block is it a true siamese bore, BGE block has a ridge from the floor of the water jacket up to about an inch in height connecting the cylinders.
the deck is .10 thicker then the 6.1 block @ the 9.25 deck height and .135 thicker then the stock BGE at the 9.285 Height.

Bad news...it's still tight in the crank area for anything over 4.125 stroke....4.08 still needs a little notching for the oil cross passage on the passenger side rear oil drain back and major surgery for the 4.125 and larger stroke.

for the NON-VVT crowd it's basically a BGE version of the old 6.1 block.....Better cooling, thicker deck and cylinder walls that don't move around above 18lbs of Boost. .(it's the Block you Need Dragula for your Eddelbrock heads)
HP wise...BGE's will go 1500 with good caps. and 4.10 max bore, 1300/1400 with 4.125-4.165 before the break...these should go 1800 at least with a good tune and 4.10 bore..not sure how well they'll take a 4.20 bore and BIG boost.

BMP Alum Block is going to drop some time around late October and early December....that will be a real game changer .......I haven't talked to Darren @ KB in a while I know they are close to releasing their block.
Future is looking a little brighter for the G3 crowd.......there will be 4 Alum block options this time next year...now how long will they stay in production.....I don't know.

Next up is a Head that'll flow....VERY well....I mean VERY well...Think AJPE or Frankenstein P48 Hemi well....and true 6 bolt around the cylinder and uses 5.60-5.80 length valves......Not 5.14