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Dyno results on my '70 ' Cuda

Started by usraptor, May 04, 2020, 04:40:20 PM

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usraptor

Took the Cuda to Horsepower Unlimited in Clearfield, Utah today to have the carb adjusted and have it dyno tested.  Unfortunately when it got up to 4850 RPM, at 130 MPH on the dyno, it developed a very significant vibration and Don didn't push it any harder not wanting to have something come apart which I appreciated.  As you can see in the video the rear tire is balling up and that's probably where the vibration was coming from.  I guess those BF Goodrich TA radials aren't "Z" rated, LOL.  As you can see by the print outs the engine still made 556.3 HP at the crank and recorded 708.5 ft. lbs. of torque at 4850 RPM.  He explained that the computer sort of guesses at the torque figures and it was actually probably closer to 660 ft lbs.  The Cuda registered 483.8 HP and 616 ft. lbs. of torque to the rear wheels.  Don said if we could have run it to 5,500 or 6,000RPM it would have gone over 500 HP to the rear wheels easily.
For those that are interested, the engine is a 440 block, bored .030 over.  440 Source 512 stroker crank and rods with Diamond pistons.  Bullet hydraulic roller camshaft, Promax (formerly Patriot) aluminum heads, Holley dominator aluminum intake, Quickfuel 880 CFM carb, electronic ignition, TTI 1/78" headers, TTI 3" "X"pipe exhaust with Dynomax Super Turbo mufflers.  Stock A833 4-speed and Dr. Diff custom 3.23 gears in a Dana 60 rear end.

https://youtu.be/fBSuG9EXb-c

gzig5

That's impressive.  Surprised you only hit 4800 @130 without an overdrive.  Seems like I'm at 3500 or so at 80 and I've got 29" tall rear tires on it.  Was the speed reading coming from the dyno or the car, I wonder if it was slipping.  But you're right, those tires are not going to do you any favors.

usraptor

#2
The speed reading was from the dyno.  What gears are you running?  The 3:23s made a significant difference in my RPM readings compared to the 4:10s.


Msbaugh440

Well done! Who did your motor machine work and assembly? Curious if it was someone local in Utah. I'm looking at a very similar build and would like a machinist who has done one or two of these 440s before

usraptor

Bart at C&T Automotive in Orem did mine.  Really knows his stuff.  Don at Horsepower Unlimited in Clearfield, who did the dyno run, also builds engines.

nsmall

Well that is some great news.   :bradsthumb:

GoodysGotaCuda

Pretty great numbers.

Surprised they just didn't run it in a lower gear anyway. I did my pulls in third because I didn't want old tires at the time spinning that fast, the  gear efficiency difference isn't all that great.


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1972 Barracuda - 5.7L Hemi/T56 Magnum
2020 RAM 1500 - 5.7L

My Wheel and Tire Specs


gzig5

Quote from: usraptor on May 04, 2020, 05:14:54 PM
The speed reading was from the dyno.  What gears are you running?  The 3:23s made a significant difference in my RPM readings compared to the 4:10s.
I've got 3.55s.  They are great around town and the two lanes, but a long highway trip at 70+ becomes tiresome.  I can't imagine 4.10s. I'm looking into my options for an OD.

With that torque number, you can moonlight on weekends pulling stumps.

Wayne

Good numbers!  Thanks for sharing.  She is sounding good  :bigthumb:
1970 Cuda 383 4spd red on red
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RUNCHARGER

Great looking Cuda, great numbers.
Sheldon

Swamp Donkey

     Nice.  Sounds great and I love a good Dyno run. 
1973 Cuda. 340 4 speed.


Mopsquad

Those torque results are impressive.  Pretty wild watching the sidewall ripple like that.

Now you need some tires that can at least get some of that torque to connect.

JS29

That should plant you in the seat pretty deep!  :stayinlane: