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)

Dave...I would have sent my new Victor up for Kevin to test against his M-1...That would have been cool!!

Ted; If we'd had it there we'd have certainly tested it. I wish I was financially independent, all I'd do is help friends with their motors and projects. (Along with mine too) Work keeps rearing it's ugly head though so most times my time is limited. Dave

Dave....I would have sent it up on my dime...No problem!! I just think it is cool what you are doing!!

Dave sure enjoys what he does and he does not give up when faced with a problem; he likes little challenges. Without the dyno and his expertise I would've probably ruined the motor if I'd done the break in in the car. Lesson learned; carb was supposed to be ready to go (don't assume anything, check it yourself) Again, thanks a bunch Mayor Dave!!!

621 ft-lbs at 3666 rpm
562 hp at 5551 rpm

That is a low rpm torque monster. Very street friendly.
Ofcourse I would have put more cam in it, the 512 CID would still have more torque than the tires will handle on the street.

Enjoy!

Thanks 440Jim, I am going to run it a while and maybe upgrade the cam later. I know from past engines I've built these big inch mopars will take a lot of cam and still idle well.

Excellent Post... Just what I wanted to read. I will be attemting to do almost the same engine here in the future for my 70 Coronet.

World Iron Block 4.395 Bore, Callies 4.250 Stroke Crank. Pump Gas is a must. Still undecided on the Heads and Cam. Hydraulic Roller or Small Solid since I have bushed lifter bores.


What oiling system are you running on this? Transmission upgrades? Rear end? and if you could change anything (or things) what would it be? AndyF and Scotty Brown are both huge helps with these combos.

Thanks for the post.

I am running a 3/8" pickup with a milodon 6 qt hemi pan. The world 1/2" adapter would not clear the rods as I am using Mopar size rod throws. I would've preferred to use the Chevy size throws but K-1 were out of them, then I could've run a bigger pickup. But this engine wont see much more than 5500 rpm. I have an external pickup setup in the box but with the stock motor mounts it would be a chore to route the line around the mounts and the power steering box. I also am going to change the dist to an MSD unit as there is no adjustment, short of disassembling the firecore dist. The advance is only 14 degrees and to get the 36 total I had to set it at 22 degrees initial and it wanted to kick back a litte on startup. I was going go with a vacuum advance dist but they would not clear the Indy EZ heads, so you are stuck with a mechanical or take the chance and mill off some of the head for clearance. I don't have a transmission yet but put a 3.55:1 8 3/4 rearend in the Coronet.

Excellent... Thank you.

you're gonna need a bigger tire...