512 "Street Motor" Dyno Results

I built this low stressed motor for the street to run on pump gas and to be installed in my 67 Coronet. So be easy on me fellas, this is not a race motor; I just wanted a good 500 hp motor. It is a World cast iron block, 512 with 4.375" bore and 4.250" stroke, Diamond dish pistons with Indy EZ heads (75cc) ending up with a 10.2:1 cr. Scott Brown hyd cam int: 245@.050" ex: [Email]254@.050" with .565" lift. Johnsosn anti- pump up lifters and Indy 1.5:1 roller rockers. Indy dual plane topped off with a 850 Mighty Demon carb. Firecore coil and mechanical dist. (last pull was @ 36 degrees total)

I want to thank Dave's Performance (QUICKD100) for helping me out and operating the dyno and doing a lot of adjustments/troubleshooting for me the last couple of days also to Maximus_Wedges and ANDYF.

Saturday we installed the motor on the dyno and after having Some timing, fuel and Demon carb issues we finally fired it up and broke in the cam. This morning (Sunday) we pulled the plugs, changed and inspected the oil filter and inspected the rockers. After a couple of great pulls with an 850 Holley, Dave went back and setup the Demon with baseline air bleeds and richened up the primary side.

We ended up with 600 ft lbs of torque@3200 rpm and peaked at 621 ft lbs@3666 rpm and stayed around 600 all the way to 4750 rpm and not dropping off much all the way to 5500 rpm(535 ft lbs). HP numbers were 562hp@5551 rpm. Needless to say, I was very pleased with the numbers. I will try and cut and paste the numbers tomorrow. This has got one flat torque curve and should be fun in my Coronet.

nice little tq monster,should be plenty for sat night cruising

that's a great street combo. you'll have a lot of fun with it. we've done dozens of similar combos like that for street use. i hope the rest of the drivetrain is up to the challenge of that torque.
should also be very easy maintenance.

Here are a couple of dyno sheet numbers

Great street moder!! Ol Mayor Dave is doing a good job on that dyno!!

Another

NIIICE job, buddy!

You'll have a lot of fun with all that torque.

Excellent choice of components, everything works together really well.

You probably have another 20+ up top with just a bigger carb, especially with that awesome indy Dual plane. My old (and very similar) 508 loved a pro-systems 1000hp.

does the dyno have any other info like bsfc, scfm, etc? would love to see it if it does. (most do)

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NIIICE job, buddy!

You'll have a lot of fun with all that torque.

Excellent choice of components, everything works together really well.

You probably have another 20+ up top with just a bigger carb, especially with that awesome indy Dual plane. My old (and very similar) 508 loved a pro-systems 1000hp.

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The motor only was using [Email]756cfm@5900rpm.[/Email] I wasn't real happy with the BG carb, it was supposed to be tuned for this combo when Larry recieved it. The air bleeds were WAYYYY off right from BG. It was dead lean, I replaced the bleeds and installed sizes listed on their website. The carb still didn't want to run. I ended up completely disassembling and cleaning it. The primary block was screwed up from BG, looked like someone had missed the center drilling a hole and decided to try again. They ended up with a figure 8 on one side. We screwed around fighting carburation for a day. I'm quite sure we could have found some more power with more time on the dyno. We met and exceded Larry's goals for the motor though. Larry did a great job designing this little street terror.
We did all the pulls on 110race gas as we initially got a bad batch of 91. Maximus Wedges, Kevin, was kind enough to run home 30 miles and bring some 110 race gas back to save the day.
With the torque the motor makes Larry will be buying alot of rear tires this summer. Dave