Bench Racer Challenge.

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Black_Betty

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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:
 
I don't "think" 516s will support 600 HP. Especially on "just" a 383.
 
Believe that story as far as you can throw that motor.

For example, making over 600hp at the tire at average A body weight you will go around 130mph. That's enough for a 10.0-10.3 give or take a little. No way that head and cubic inch is doing it.
 
I have, in the past, posted the dyno results from a 440 with mildly ported 516 heads and the Mopar 509 equal of that camshaft.......449HP. If we bump the compression on the 440 from about 8:1 to 10:1 we would see, maybe, 485HP. Perhaps the 383 felt like 600HP but it wasn't making 600HP.

If the Dart only weighed 2500# and the 383 made 460 FWHP..........maybe the ET claim is accurate.
 
Good mention. The HP to weight factor is missing. Though I have found it all most amazing that a stock head can churn out low numbers/high speeds.

Everything is in the set up, not just the engine alone.
The old adage still applies. Big engine/light car = go fast.
 
to give you an idea of what it took to run 10.1@131 in my mates '69 Dart at 3150lbs..

440, 12.7:1CR, Eddy heads [email protected], DC. 590 solid flat tappet cam, Victor int., 1050 Dommy, 2" hdrs, 1.39 short time....N/A
13x31's, 4.56's and a 5000 Utimate verter.

So I think you got the idea about that 383.......BS.
 
Wow. Thanks for all of the fantastic input! Lots of very good points made.
A couple things that I forgot to mention. The intake manifold and 650 DP it came with don't work together because the carb is a spread bore while the intake is a Weiand 7501 square and also wouldn't support that much power. So... The mention of having forgot the nitrous may be a legit comment! IMHO, I think he kept his converter, trans, intake, NOS, and carb and threw in a bunch of random things to sort of complete the package.
If he stripped out his car, had 4.56 gears, slicks, and the rest of the correct parts on the engine, I would be able to see 10's but 600 HP, is a pipe dream. In its current setup, assuming the carb and intake worked together, I would be happy with a 12.99.
 
The motor built as described is not even in a catagory to run low 10's! Another member gave the recipe for what it takes to run low 10's, and this motor had none of the items needed for that kind of power! And yea, sounds like he took the good stuff and threw a bunch of junk on it to make it "complete"!!!
 
Well it sounds like the engine may be exactly what I was looking for. It's going into a 68 Dart GT convertible and too much power would tear it apart. It is supposed to be a driver, not a race car. So, it'll probably sound the part, but be more drive able than it sounds. Thanks for all the input. It just confirmed my suspicions.
 
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