Bench Racer Challenge.

Here's the game. I have some info, am missing some info and am asking for some info.

What I know: 1966 383 that is .030 over. Double roller chain. Flat top Pistons with no valve reliefs cut. The cam is a Comp Cams PP292H part number 21-672-4 with a stock stamped 1.5 ratio rocker setup. The heads are a 516 casting that have been port matched and mildly ported. Double valve springs are installed. The transmission that I got with the engine is a 727.

What I was told: engine and trans were run in a 69 Dart. I believe this because it has the oil pan for an a body to clear the idler arm. The converter was a 4500-4800 (not the one I got with the trans) and here's the big one... APPARENTLY the engine has 4 passes on it. Best time was 10.20. MPH unknown. Boasted HP was 600...😕

What I am clueless on: (among other things lol), rear end gears that were run, anything else about the donor car.

What I'd like to know: Assuming the things I was told are true and the things I know, is it even possible for the car to have run what they say. The guy who drove it said he wanted 9's so he went 440. He has since passed away.

I have doubts mainly because I don't think that those heads can flow enough. I'm sure there are some great opinions here. BTW, the combo didn't cost me anything, so I won't be hurt if it isn't true. Relieved actually. :happy1: