Yeah, it should be around 850 hp or so. It ran 8.50 in my 2000lb altered at 5800 ft in denver. 8.11@163 with a 150 shot. At lower altitude you can figure .6 sec faster. Wish I would have went back to Kansas and raced it before I got rid of the car. It went 8.000 one time at great bend before I had the heads ported. Ported the heads before I ever ran at denver but it seems to have picked up .5 sec. or so. My buddy from there runs 7.70's in kansas and 8.30's when he comes to denver. May never get in the 7's now with a heavy old chevelle! Anyways, it seems I may not want to hit it with a 300 shot. I'd rather not blow it up and crash the car. Heads flowed right under 400 cfm after the port job, 310 cfm before! Just some junk old 305cc brodix -2's. Block is not a bowtie. Wonder why Shafiroff ever put these together without a dart block? Has anyone seen any actual problems with these or is everyone just worried like I am? Sounds like the cylinder walls are a bit thin is the problem.