Horsepower question

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425 horsepower. 450 torque.
The cork is the STOCK EQ heads.
Add 50 cfm, you'll have 470.
My worthless opinion only.
Cylinder head flow charts will tell you what to expect.

Edit: Stan Weiss head charts show the stock EQ at (roughly) 230cfm in, 180ex.
Ported, about 40 cfm better, in/ex.
I would not spend the money it would take to get that out of iron heads.
Stock iron, or ported aluminum heads, please.
 
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How much horsepower can ya make with a 408 with 1.92 valve heads
For any combination of other parts, it will make less torque and power everywhere in the rpm range, than a larger valved head that flows more.
 
OK this is a motor I had built by someone who is supposed to be reputable I don't want to get to far into the situation at this time until I get my parts back and see how I'm treated with all that.
I thought the numbers seamed high and was just wondering if my feeling was right and they seamed as 273 said a little fishy
 
OK this is a motor I had built by someone who is supposed to be reputable I don't want to get to far into the situation at this time until I get my parts back and see how I'm treated with all that.
I thought the numbers seamed high and was just wondering if my feeling was right and they seamed as 273 said a little fishy
Do you have the engine in your possession? Why not just take it to another dyno? Then all the speculation and guessing can stop.
 
Let’s bench race a little shall we? Maybe day dream, or play the percentages game? We all know how math can be sometimes but here it goes. This weekend, like yesterday, I made 388 wheel horsepower on a chassis dyno. Through a horribly inefficient 46re transmission and a 3:55 geared diff on 28” tires. Let’s say I had 30% drivetrain loss. If that’s good bench racing math then my 1.92 valve size, stock headed magnum 360 is making, wait for it………504hp. If I had only 20% drivetrain loss the same engine made 465hp. Now your 470hp EQ (hint: way better than stock magnum) headed 408 doesn’t seem that far fetched. They’re just numbers. The EQ heads are pretty good. Put that junk in a car and go rip it. If it’s too slow, make it faster.
 
OK this is a motor I had built by someone who is supposed to be reputable I don't want to get to far into the situation at this time until I get my parts back and see how I'm treated with all that.
I thought the numbers seamed high and was just wondering if my feeling was right and they seamed as 273 said a little fishy

Post the fuel flow and OBSERVED power and torque numbers.
 
Are the heads on the engine “original” EQ heads from NZ……..or the current Chinese offerings?
In ootb form, I’m pretty sure the current offerings aren’t great from a flow standpoint.
 
stock eq heads supposedly from Australia
Are the heads on the engine “original” EQ heads from NZ……..or the current Chinese offerings?
In ootb form, I’m pretty sure the current offerings aren’t great from a flow standpoint.
Post 28 I took that as he’s got the original “good” EQs.
 
If it's a 1971 408 then you can make 375hp. If it's a 2025 408 then you can make 2000hp.... For some reason engines nowadays claim to be making rediculously more hp than back years ago... It seems scammy. :wtf:
 
Saw an engine power episode, a few days ago, where they dynoed a 5.9 Magnum, pretty much stock, then stroked it to 410, and dynoed it again, after re-assembly with all the stock 5.9 Magnum parts, but with a 950 cfm carb.
I don't remember the exact numbers, but roughly 305 for the 5.9, 335 for the stroked 410 wow, disappointing! 30 horsepower for roughly 50 cubes.
Next episode they hopped the 410 up. Tf heads and single plane intake, 40 degrees more duration in the roller hydraulic cam, and good valvetrain parts to make it all work, plus a 1000 cfm (rated, I don't believe it) carb. Final tune made approx 550 hp.
Parts combo seems to make a bit of difference, hunh?
The TF heads are reported to be 60-70 cfm better than the good EQ heads, So, by the 2hp/cfm standard, maybe 120 hp better? (With a good matching intake).
 
but roughly 305 for the 5.9, 335 for the stroked 410 wow, disappointing! 30 horsepower for roughly 50 cubes.
With everything being the same that's all I'd expect, like the difference between a 383 magnum vs a 440 mag.
 
Saw an engine power episode, a few days ago, where they dynoed a 5.9 Magnum, pretty much stock, then stroked it to 410, and dynoed it again, after re-assembly with all the stock 5.9 Magnum parts, but with a 950 cfm carb.
I don't remember the exact numbers, but roughly 305 for the 5.9, 335 for the stroked 410 wow, disappointing! 30 horsepower for roughly 50 cubes.
They also added around 2 points of cr when going from 305 hp to 335 hp, with the stroker kit.
 
Saw an engine power episode, a few days ago, where they dynoed a 5.9 Magnum, pretty much stock, then stroked it to 410, and dynoed it again, after re-assembly with all the stock 5.9 Magnum parts, but with a 950 cfm carb.
I don't remember the exact numbers, but roughly 305 for the 5.9, 335 for the stroked 410 wow, disappointing! 30 horsepower for roughly 50 cubes.
Next episode they hopped the 410 up. Tf heads and single plane intake, 40 degrees more duration in the roller hydraulic cam, and good valvetrain parts to make it all work, plus a 1000 cfm (rated, I don't believe it) carb. Final tune made approx 550 hp.
Parts combo seems to make a bit of difference, hunh?
The TF heads are reported to be 60-70 cfm better than the good EQ heads, So, by the 2hp/cfm standard, maybe 120 hp better? (With a good matching intake).
Simply put, they were selling heads my friend... Trickflows.
Stock magnum cam is verrrry small.
1.92 intake valves not ideal, anemic coupled with bone stock ports for a 4" arm. Magnum port volume is verrrry small... smaller than stock LA 360 as well. That was left as it was designed by the factory....a truck motor... they just upped the stroke .420 more.

I wish that.. when they do tests like these.. that they would do a bolt on run through...then one with optimization of the heads via camshaft and play with both dual and single plane intakes.
 
Oh, I definitely realized they intentionally handicapped the stroker combo. To increase displacement substantially, and then do NOTHING to improve airflow is either really stupid...... or intentional.
Edit: I forgot to mention, the truck motor version of the 410 made around 500 ft/lbs, at truck rpm.
 
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I see it more as just a curiosity test, instead of just going from stock 5.9 to full 410 TF build, they probably figured "I wonder what the 410 would do with 5.9 top end" type thing, not everything is an conspiracy :)
 
Thank you all for the input at this time I'm believing the results from the Dyno sheet the numbers could be correct once the motor goes back n the car I will have it tuned for the sniper and get numbers then
Again thank you all for your help
 

He hasn’t posted a dyno sheet yet and he won’t as he doesn’t want to hear what FABO has to say about it. Kim
 
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He hasn’t posted a dyno sheet yet and he won’t as he doesn’t want to hear what FABO has to say about it. Kim
You are correct I haven't but the sheet I have only shows the tq and hp curve but it's gonna be a minute till it gets reassembled and back in the car
 
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