No Replacement for Displacement (myth or fact)

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crackedback said:
Your ET/MPH simulations are REALLY aggressive. 480FWHP is going to be lucky to run 10.9x0/121ish at 3400. It's going to need to leave REALLY hard with superior 60' times to get to the 10.9x range.

Read Moper's comment over and over. It's about the overall package.

What works well for a 340 may not and likely will not be good with a 4" arm.

The BIGGEST reason that the "No replacement" comes about is because it's easier to meet an HP goal when you start with a bigger pump. If I want 550 HP, it's easier to get 1.1hp/ci out of a 500" engine than 1.6hp/ci out of a 340. Plus the range is much lower on the 500" engine, easier on valvetrain, etc.
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I agree with what your saying, if your power need start to go above 1.2hp per cubic or over 6000rpm on a street car it's probably time to go with a bigger engine especially if it see lots of miles. But I guess why I wrote this is people latch on these ideas and take it to far like there was a thread a while back
340 vs 360 and in most people's minds a 340 was no match for a 360, But too me they both will make similar power with similar work and yes the 360 will make more torque and if geared right both with have similar performance but if you run 3.55:1 gears in both than yes 360 all the way that's another thing I believe if your not gonna gear your car properly than run the bigger engine don't run a 273/318 with highway gears unless its a very mild build.

On the drag simulator I had everything set to optimal.
 
Rodzilla said:
You are correct, if your going to build a 416 with all the wrong parts, a 340 will come out the winner! ;-)
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How many A-body's are running around with 10CR, Eddy's or RHS, Air Gap, and .550 lift cams in 340/360 or 408/416 combos and they all seem to make the same power give or take 25hp.
 
how many of the combo above does the owner truly knows how much hp he has...?

probably got some inflated hp number from the dyno or followed the build from a inflated magazine article...and wonder why it runs like crap..
 
Rodzilla said:
You are correct, if your going to build a 416 with all the wrong parts, a 340 will come out the winner! ;-)
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What would the right parts for each engine be with a 340 and 416 so I could run it through my program and what the difference would be?
 
personally...unless the your program prints out an ET slip....I would find it useless....JMO...
 
273 said:
How many A-body's are running around with 10CR, Eddy's or RHS, Air Gap, and .550 lift cams in 340/360 or 408/416 combos and they all seem to make the same power give or take 25hp.
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Same topend = more torque in stroker >>> Dispacement wins even if HP numbers are close.

But like mentioned by moper, research and optimize what ever build you want to do. You need to consider what your car has for the rest of the drivetrain, what you want it to do and/or what changes your willing to make. I love my barely streetable stroker because I can still drive it around at reasonable rpms, don't need a 5500stall (mines a 3200) like a 340 with same topend (Indy) would need for equivalent power.
 
70aarcuda said:
personally...unless the your program prints out an ET slip....I would find it useless....JMO...
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It actually does but I know what you mean that you got to prove on the track.
I don't how I double posted this
 
70aarcuda said:
how many of the combo above does the owner truly knows how much hp he has...?

probably got some inflated hp number from the dyno or followed the build from a inflated magazine article...and wonder why it runs like crap..
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70aarcuda said:
personally...unless the your program prints out an ET slip....I would find it useless....JMO...
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EXACTLY!!!

I've seen/read of engines with claims of 570-600hp only run 120-121 in a 3000-3200# car.

That hp and wt should EASILY run 125+ and into the 127+ range. Watch any episode of pass time and you'll get the feel for the BS hp numbers floating around.
 
Rodzilla said:
Same topend = more torque in stroker >>> Dispacement wins even if HP numbers are close.

But like mentioned by moper, research and optimize what ever build you want to do. You need to consider what your car has for the rest of the drivetrain, what you want it to do and/or what changes your willing to make. I love my barely streetable stroker because I can still drive it around at reasonable rpms, don't need a 5500stall (mines a 3200) like a 340 with same topend (Indy) would need for equivalent power.
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I looked at your engine combo on your build by the way nice Demon, I see what you mean that your 416 would be on the edge of streerable and a 340 would be race only but do think a 340 built like your 416 would make the same power + or - 25hp? I agree with Moper and you to research and optimize my combo this is part of my research.
 
273 said:
I looked at your engine combo on your build by the way nice Demon, I see what you mean that your 416 would be on the edge of streerable and a 340 would be race only but do think a 340 built like your 416 would make the same power + or - 25hp? I agree with Moper and you to research and optimize my combo this is part of my research.
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Ya, I think HP could be close, not sure, but maybe need more cam with the 340, she will have to sing (like 7500+ RPM) for 600HP(or close, I will dyno this winter). Hence the need for Big Stall number. But I'd rather have that power and much more torque(that also comes on quicker) in a more street friendly version.

inkjunkie said:
Don't think you find many, if any, small blocks where this guy is headed....http://www.forabodiesonly.com/mopar/showthread.php?t=174684
just saying
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Darryls car is awesome, and going to be on the street, crazy!! I sure hope he puts Larsons Nova in its place(not 1st) next year!!
 
i agree with the weight part too. a buddies car was the 4 banger turbo. not the most hp but because it was so light it made it "faster"

i am waiting for the race between my dads um.. chevelle 383 vs my little duster 360. i weigh 900 pounds less, but a smaller motor.

i love seeing big block huge motors that only put out a hundred more hp then a beefed sb, with sarcasm of course
 
One things have forgotten to take into account. The bigger the part the more wear and greater chance of failing. Vs a small part with less weight can move faster and do it longer with wear and less chance of failing. Example is that in racing (for extended time) a smaller motor with small parts (like a 4.6l v12 motor) with have less wear then a big motor (like a 408/416/426 sb motor) with its heavier parts and higher rate of wear. But it all really comes down to the valve train! A dual overhead cam design with 4 valves per piston can and will take more HP/Rpm/stress then a standard Pushrod based motor with two big valves.
 
To a certain extent..yes, however a car with the right weight distribution,proper rear gear and converter can kick serious a$$. Combination is king!
 
In a perfectly controlled lab environment, the theory is sound, however, as I'm fond of saying...

"in theory, theory and practice are the same...in practice, they are different"

If you build a 340, and then replace only the short block with a 416 with comprable parts...I'm fairly certain the larger displacement incarnation will be more powereful.

Of coures this also then brings up the question...

Why do people idolize the 340, but shun the 360?


...and how about a 2 stroke cycle?

Not exactly more fuel efficient, but other effieiencies come into play, and power is nearly doubled vs a 4 stroke cycle.
 
Rodzilla said:
Ya, I think HP could be close, not sure, but maybe need more cam with the 340, she will have to sing (like 7500+ RPM) for 600HP(or close, I will dyno this winter). Hence the need for Big Stall number. But I'd rather have that power and much more torque(that also comes on quicker) in a more street friendly version.
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Thats all I'm trying to get across that adding Cubic Inch Isn't gonna magically add to peak HP but only effect where it peaks and with proper
gearing and stall setup will be just is quick. Not really debating the merit
of small vs large displacement and streetablity and durability if I wasn't
gonna autox my Cuda I'd go 451-470 Stroker Big Block.
 
YY1 said:
In a perfectly controlled lab environment, the theory is sound, however, as I'm fond of saying...

"in theory, theory and practice are the same...in practice, they are different"

If you build a 340, and then replace only the short block with a 416 with comprable parts...I'm fairly certain the larger displacement incarnation will be more powereful.
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Most of the time 416 gonna be faster than a 340 with a similar build cause most people don't gear thier cars properly.
 
If you are thinking is it better to build a 273 over a 360/408 stroker, build the biggest cubic inch engine you can

For one you can get more goodies for the 360 block over a 273

400 hp out of 360 very common, a 273, at what cost

Only reason to build the 273 is if you are completely restoring car stock, put a set of 273 hipo valve covers and air cleaner and it will have the look, but inside a real runner
 
Rodzilla said:
Untill more cubes comes along with same efficiency ;-)
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Well of course. Not saying they're not important. But in at least one sense, you can get more power out of a smaller displacement engine by making it more efficient ^^ Just in the short term. In the long run, more of both is obviously better.
 
Explain a 2.4 liter Naturally Aspirated V8 making over 800 horsepower. I guess when the rev limiter is set at 18,000 rpm it helps. [ame="http://www.youtube.com/watch?v=-P3xPlishXw&feature=relmfu"]F1 Car in Lincoln Tunnel - Full Edit - YouTube[/ame]

I can't wait for the race in a couple of weeks. Awesome season, Go Vettel!
 
273 said:
Thats all I'm trying to get across that adding Cubic Inch Isn't gonna magically add to peak HP but only effect where it peaks and with proper
gearing and stall setup will be just is quick. Not really debating the merit
of small vs large displacement and streetablity and durability if I wasn't
gonna autox my Cuda I'd go 451-470 Stroker Big Block.
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I think I would want a higher Erving engine if participating in auto x. Maybe make it a little easier to keep it in the power band
 
DobaDaddy said:
I think I would want a higher Erving engine if participating in auto x. Maybe make it a little easier to keep it in the power band
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Ya I think 273 will meet my needs, 90% of the times I agree build a 360 instead but I only need 400hp + or - 25hp but a 400HP 360 would put me in a way higher class than a 400hp 273 plus I love rpm's and not afriad of gearing her up 4.88:1-5.?:1 plus it's a challenge.
 
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