Guess!

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410 and 435 @ 5,500
And TrailBeast is the hero of the day! :thumbsup: He's darn near clairvoyant.:D Lots of good guesses, and I appreciate the feedback.
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With some of the early guesses, I wondered if I was missing something, like maybe dog grooming. Honestly, I was hoping to hit 420 hp, but dyno time is expensive, and I wasn't going to get greedy on my dime. The customer was satisfied, so I left it be, even though there were a few more left. We didn't even pull plugs to look at fuel distribution between cylinders. Too much time wasted fitting the customers headers. With the dual plane, some staggered jetting may have netted a couple more numbers. Overall though, I guess it turned out ok.

I was a little surprised that it wanted so much timing. It has good quench, and stock heads with quench don't usually want near that much, in my experience.

This motor is a perfect example that you can make good torque numbers with a low DCR. Once the motor spins faster than cranking speed, inertia and ram tuning takes over, and the DCR has less effect on cylinder pressure as the volumetric efficiency increases.

It should work well in the customers application, but I recommended he throw a 3.91 gear in the rear eventually for better street/strip performance. With the right chassis setup and converter, low 12s or better should be possible.
 
And TrailBeast is the hero of the day! :thumbsup: He's darn near clairvoyant.:D Lots of good guesses, and I appreciate the feedback.
View attachment 1715043139 View attachment 1715043140
With some of the early guesses, I wondered if I was missing something, like maybe dog grooming. Honestly, I was hoping to hit 420 hp, but dyno time is expensive, and I wasn't going to get greedy on my dime. The customer was satisfied, so I left it be, even though there were a few more left. We didn't even pull plugs to look at fuel distribution between cylinders. Too much time wasted fitting the customers headers. With the dual plane, some staggered jetting may have netted a couple more numbers. Overall though, I guess it turned out ok.

I was a little surprised that it wanted so much timing. It has good quench, and stock heads with quench don't usually want near that much, in my experience.

This motor is a perfect example that you can make good torque numbers with a low DCR. Once the motor spins faster than cranking speed, inertia and ram tuning takes over, and the DCR has less effect on cylinder pressure as the volumetric efficiency increases.

It should work well in the customers application, but I recommended he throw a 3.91 gear in the rear eventually for better street/strip performance. With the right chassis setup and converter, low 12s or better should be possible.

That was fun. Do another one!
 
Nothing wrong with the HP or TQ numbers. Should be a runner.
Thanks! I do like the torque curve. It holds 437 lbs/ft from 3800 to 4200 rpm, and over 400 from under 3400 to over 5200 rpm. That should make an A-Body pretty quick.
 
That was fun. Do another one!
Well, I don't have another SB in the near future, but I will be dynoing a 505 BB in the next few weeks. We can carry the fun over to the big block forum.
 
Well, I don't have another SB in the near future, but I will be dynoing a 505 BB in the next few weeks. We can carry the fun over to the big block forum.

Not my usual ball park but I am game.
 
And TrailBeast is the hero of the day! :thumbsup: He's darn near clairvoyant.:D Lots of good guesses, and I appreciate the feedback.

My Motor is pretty much identical except for the Edelbrock 600 so I kinda cheated.:D
 
My Motor is pretty much identical except for the Edelbrock 600 so I kinda cheated.:D
Well, I guess there had to be someone out there with that combo. Why not you, right?:D Good call! Now, for just a nominal processing and handling fee, you get a your choice of a free ShamWow, or a gallon of Flex Seal for your screen bottomed boat. Woo wee!:lol:
 
where do i get the 120 degree thermostat?
That's were Barton's dyno guy usually makes their pulls. I would rather use oil temp, but hey, its their toy. Repeatability was surprisingly good.
 
Well, I guess there had to be someone out there with that combo. Why not you, right?:D Good call! Now, for just a nominal processing and handling fee, you get a your choice of a free ShamWow, or a gallon of Flex Seal for your screen bottomed boat. Woo wee!:lol:

I'll take the flex seal, thank you.
I thought I would never get to use my submarine because it only has a screen door.
Bought it off the Wife of a Chevy owner that passed away somehow for pennies on the dollar.
 
I'll take the flex seal, thank you.
I thought I would never get to use my submarine because it only has a screen door.
Bought it off the Wife of a Chevy owner that passed away somehow for pennies on the dollar.
Ha, let me guess. Cause of death.....drowning! Lol
 
It should work well in the customers application, but I recommended he throw a 3.91 gear in the rear eventually for better street/strip performance. With the right chassis setup and converter, low 12s or better should be possible.
Can you tell us the customer's intended application?
 
Why dont they run the water temp at a 180 where the engine is going to be run on the street?

And I know the answer...more HP at the lower water temp...
 
Can you tell us the customer's intended application?
Some good guesses here, but some are giving the "untouched" heads too much credit. They ain't all that right out of the box.

The LSA is 110, installed at 105. The application is for a 75 Dart with a 904 and 3.55s. Mostly street, occasional strip.
 
Why dont they run the water temp at a 180 where the engine is going to be run on the street?

And I know the answer...more HP at the lower water temp...
Actually, heat is thermal energy, and it might have made more at higher coolant temps. Air temp, not so much.

I like to use oil temp because it is a better indicator of the internal temps of engine components.
 
Every dyno sheet that is ever post on this web site...shows the water temp low....so there must be something there to help sell the hp numbers...just like the Corrected Hp numbers...but I dont know where you find 60 degrees temp..with 29.92 baro and no humidity....The dyno sheet should show Actual HP along with the Correct so someone really knows what they are buying..
 
That's egzactically what I was thinking!
Do I get anything for nailing the rpms? Or at least the Torque-peak.
Ok ok. An honorable mention to TrailBeast and Desert Rat for nailing the peak HP rpm, and to AJ/FormS for nailing the torque peak. And everyone else gets a participation trophy.:D
 
Every dyno sheet that is ever post on this web site...shows the water temp low....so there must be something there to help sell the hp numbers...just like the Corrected Hp numbers...but I dont know where you find 60 degrees temp..with 29.92 baro and no humidity....The dyno sheet should show Actual HP along with the Correct so someone really knows what they are buying..
Those are the correction standards. If the customer drives to the beach, he will have more horsepower. If he drives to the mountains, he will have less horsepower. That's the whole purpose of the correction factor. If you live in Denver, and buy a motor dynoed in Ocean City at 400 actual horsepower, you are going to be very disappointed. The correction factor allows for a close apples to apples comparison. Actual numbers have their value, but not for comparison between engines.
 
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