Maybe subject already beaten to death. Just curious if anyone knowns how much HP a factory production Hemi stock block has made ?
Including Nitro, Alcohol, gas..

Allan G.

Are we talking vintage or new?

I used one new 426 Mopar brand hemi block, not sure who made them then, it was not a World block. (It was purchase before the world blocks were offered) It was a 4.180 unbored non siamese block that we sonic tested and ended up boring it to 4.250 because it was not real thick in the cylinders like it should have been We bought a used Crower 4.375 stroke forged blower crankshafts with the center counterwieghst I used that block to build a blown motor with a 10.71 Littlefield blower with two 1050 blower Dominator carbs, custom ground solid roller cam , Oliver billet steel rods, custom blower pistons with 9.7 to 1 comp. ratio, it was going to be a pump gas street motor, and some other good parts like Stage V ported heads, Landy roller rocker arms and so on. The motor made 925 HP at 7300 RPM with 7.5 lbs of boost on pump gas with 33 degrees of toatl timing and 1027 HP at 6500 RPM with 12 lbs of boost on race gas with 25 degrees of timing, I should have ran less timing than 25 degrees total with the incrreased boost but we ran out of dyno time and the customer said that was enough HP for his street car That customer never drove the car on the street after the dyno session He sold it

My pops old KOS car had a new mid 90's street hemi block. 484ci, early dart/stage 5 heads. quite a bit of nitrous, enough to go 8.2 something at almost 170 3450lb cuda. I think with the newer technology (digital 7 boxes etc.), and so much better converters and nitrous tune-ups it could go high 7's with ease nowadays. Block had hundreds and hundreds of passes and still is in the car right now, but hasn't been run since 2002.

They used to claim around 2500 HP from a nitro engine back in the 1960s. That was iron heads, 6-71 blower, etc.

A good friend was the crew chief on the Bob Banning funny car back in the early 70's. The most runs they got out of a stock block was about 70. He said the block would split straight up from the main web to the cam and when he had to chisel the main bearings out because they flowed into the crack too far, he knew it was time to trash the block. Heads didn't last anywhere near as long. They use to send him pallets of heads