famous bob
mopar misfit
dis agree , a 750 horsepower engine w/ 700 ft lbs of torque would kill it , in the same weight car, w/ traction.
Undersquare vs. Oversquare Engines
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dis agree , a 750 horsepower engine w/ 700 ft lbs of torque would kill it , in the same weight car, w/ traction.
67Dart273
Well-Known Member
No, opposite. A short stroke big bore engine is "oversquare"
I disagree lol
Torque at the crank don't matter its torque to the ground, if geared right both would have similar torque to the ground (actually hp).
Which one that had the better hp curve should win. But with the F1 engine it would be hard to find a deep enough gear and high enough stall lol.
Naaaa, it can be done
MOPAROFFICIAL
Oogliboogli
This is like 440 vs 426 hemi but not ,but like....
Gear the short stroke motor and it's heads even in the constraints given will out flow and power the sb offering .
Same heads, literally, then the stroke will poke.
Gear the short stroke motor and it's heads even in the constraints given will out flow and power the sb offering .
Same heads, literally, then the stroke will poke.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Here's food for thought; all are about 344 cubers, and all SBMs
4.06x3.315....3.91x3.58.....3.80x3.79.....3.70x4.00
Put the same small-valve heads on each of them, for obvious reasons.
Which would you rather have?
Well that depends on the application....right?
But optimize the valves and then what?
4.06x3.315....3.91x3.58.....3.80x3.79.....3.70x4.00
Put the same small-valve heads on each of them, for obvious reasons.
Which would you rather have?
Well that depends on the application....right?
But optimize the valves and then what?
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67Dart273
Well-Known Member
426 hemi has the same stroke as any RB engine so ??????
You are talking strictly the difference in heads / piston dome? Then yeah.
And then.....
The hair splitting!!! And, one upmenship, but's, what if's, bigger that, recontoured this, I can do this, I can do that, I get better with this.....
OMG! IT'LL never end!!!!
I had a friends who's cousins uncle...
famous bob
mopar misfit
Smoked pot ?
yellow rose
Overnight Sensation
famous bob
mopar misfit
famous bob
mopar misfit
Not according to bill Jenkins, get one of his race trick books and read it. I didn`t care for him, but he was a pretty darn smart guy.
Both basically have the same torque, theres no free lunch. The 700 lbs-ft engine is obviously twice the size and turn half the rpms then the 350 lbs-ft engine. So for every one revolution of the larger engine the smaller one is doing two. Torque is basically a snapshot of one revolution and hp is them all added up over time. So if you look at both engines here there both doing 700 lbs-ft in the same moment. 1 x 700 = 700, 2 x 350 = 700.
To access the smaller engine potential we would need about twice the gearing which would put the same torque to the ground.
So both engines have the same hp and torque. Again the better hp curve should win.
Thats why we use hp to compare motors it takes acount of all the torque an engine produces not just one revolution.
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famous bob
mopar misfit
I agree. IMO, I think 273 spends to much time inthe calulators like AJ. Real world suggests otherwise.... OH wait, sporty, proves otherwise.
Application dependent of course....
Cause a tractor has no power. Gearing can't create power. It can only get you into the powerband. The ultimate gearing would be a variable transmission that would keep you at peak hp through out the 1/4 mile. Or any high work loads. Thats why rock crawllers run crazy gearing so to be up in the powerband (hp) while driving at low speeds.
But both of the above engines (700 vs 350 lbs-ft) have the same power. Just different torque. And if you gear them optimally for the 1/4 you'll out they'll have similar torque to the ground. But really more important be at similar hp per mph, given them similar power to the ground depending on the hp curves.
Cause you get nothing for free. When you build to wildly different displacement engines to the same hp one is gonna trade rpm for torque and the other is gonna do the opposite. And If rpm wasn't just as valuable as torque for the reasons I explained earlier. It wouldn't be apart of the hp formula.
The 5252 part is mainly to convert the engines power to compare with horses leaving torque and rpm to explain your engine power.
If torque plays a big role in quarter mile times how come there no formula or rule of thumb etc.. for optimal torque ?
We all know power to weight does.
famous bob
mopar misfit
Still off!, I grew up on a farm w/ 5 diff type tractors on it, they don`t have to be wide open to do their job, the powerband thing don`t cut it in them. One of our tractors had a 6 cyl. Chrysler car motor in it, it was scary fast on the road w/ no governor, another super M was as stout w/ a 4 cyl engine , but certainly not the fastest . As I SAID GEARING DOES NOT CREATE TORQUE, but will cover up a lack of...............
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Just multiplies it!
A tractor really has no brearing on your original point. No amount of gearing will make it a top fuel dragster. Again gearing don't do much cause the engine has little power in the 1st place.
Your original point was a 700 hp 700 lbs-ft will smoke a 700 hp 350 lbs-ft cause of the torque difference. Which I point out among other things if both geared properly for the 1/4 mile both will be putting similar torque to the ground nullifying the difference at the crank. But that only works if comparing two engines of the same/similar power.
My point is you don't gain extra power by building 700 hp at a lower rpm then another engine making it at high rpm. Cause when setup right (stall gearing) the differences (torque) will be the same at the tire.
Why cause your not gaining anything. Thats why they both make the same power. But the larger engine will trade rpm for torque and the smaller one do the opposite.
Oh jeeezzzzz
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