340 Vs 360

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Combine the two...

Get a 340 block that will go .030 to 4.07, or even .040 to 4.08

Find a 360 crank CORE, (probably free if you look) and since it will have to be turned anyway...turn the mains down to fit the 340 block.

Shelf (hyper = cheap) pistons are available and with a light SCAT rod, you'd have 372+ tire shredding cubic inches inches! HUGE bang for the buck, it you ask me.

Seems like I see a few reasonably priced 340 cores her in CA every week...
 
Combine the two...

Get a 340 block that will go .030 to 4.07, or even .040 to 4.08

Find a 360 crank CORE, (probably free if you look) and since it will have to be turned anyway...turn the mains down to fit the 340 block.

Shelf (hyper = cheap) pistons are available and with a light SCAT rod, you'd have 372+ tire shredding cubic inches inches! HUGE bang for the buck, it you ask me.

Seems like I see a few reasonably priced 340 cores her in CA every week...
all you would have is a .070 to .080 overbored 360 with .300 cut from the mains of a cast crank. "huge bang for the buck" hardly.......more like a huge cut from your wallet.
 
only about 85 % (on average) of what is brought into the cylinder is ACTUALLY burned. The 340 does about 15-20 % more cfm's at 5000 rpm's. Hmmmmmmmmmmm.?????......... So if a 340 is actually only consuming 84%, and a person can get the 318 to burn 98 %, given the fact that heads, cam, intake/carb and exhaust are equal, then the 318 does NOT need to "twist higher". You see, on the dyno, cfm's are measured, efficiency is NOT!!!!!! That's why gross horsepower went away and net came into play. Never mind, I should start a thread called "new light"..... and maybe I will..... hmmmm


Stoichiometric ratio allows 100% of oxygen to be burned during combustion.

A dyno doesn't measure CFM, it measures torque output and RPM (and horsepower as a result)

CFM is a measurement of airflow, often used to estimate volumetric efficiency.

Gross horsepower is a measurement of horsepower with no ancillaries such as water pump, oil pump, radiator fan, power steering pump etc.

Net horsepower is the engine's output as it would realistically be to the transmission in an actual car, with all of the above power-sapping necessities connected

Everything being equal, (proportionate to displacement) A larger motor will always produce more overall torque than a smaller motor. This is scientific fact and cannot be refuted.
 
Stoichiometric ratio allows 100% of oxygen to be burned during combustion.

A dyno doesn't measure CFM, it measures torque output and RPM (and horsepower as a result)

CFM is a measurement of airflow, often used to estimate volumetric efficiency.

Gross horsepower is a measurement of horsepower with no ancillaries such as water pump, oil pump, radiator fan, power steering pump etc.

Net horsepower is the engine's output as it would realistically be to the transmission in an actual car, with all of the above power-sapping necessities connected

Everything being equal, (proportionate to displacement) A larger motor will always produce more overall torque than a smaller motor. This is scientific fact and cannot be refuted.

You sound intelligent, but you are wrong. Actually, means you want to be scientific, a motor gets its power source from an outside source, such as a battery or electricity. An engine makes its own power from within, usually combustion. So, your quote of a larger displacement (you said motor, but I think you meant engine) will ALWAYS produce more torque is incorrect. You see, a 5.9 diesel is an engine, and it will produce much more torque than a 5.9 gasoline engine, but by your theory they would be equal. And, as a rule of thumb, nobody is burning 100% of whats brought into the cyl. This is why EGR valves look to re-burn the "unburnt" fuels, and a reduction in emissions. This is why splitfire plugs were invented. This is why people spend money for better plug wires, hot burning electronics to fire that plug. Stroke is bottom end torque. Same displacement cubic inches will not always perform the same. If one gets there by bigger bore and less stroke, the engine with the greater stroke will have more low end grunt. Think of a bicycle. Your legs are the piston, the "WAM"! but the length of which the pedal is attached (crank) would be your stroke. A little less leg can out perform if the crank of which the pedal is attached is much longer. Maybe the person x crank would be less than but torque could be greater than. There, lol.....
 
th_caution.jpg
 
You sound intelligent, but you are wrong. Actually, means you want to be scientific, a motor gets its power source from an outside source, such as a battery or electricity. An engine makes its own power from within, usually combustion. So, your quote of a larger displacement (you said motor, but I think you meant engine) will ALWAYS produce more torque is incorrect. You see, a 5.9 diesel is an engine, and it will produce much more torque than a 5.9 gasoline engine, but by your theory they would be equal. And, as a rule of thumb, nobody is burning 100% of whats brought into the cyl. This is why EGR valves look to re-burn the "unburnt" fuels, and a reduction in emissions. This is why splitfire plugs were invented. This is why people spend money for better plug wires, hot burning electronics to fire that plug. Stroke is bottom end torque. Same displacement cubic inches will not always perform the same. If one gets there by bigger bore and less stroke, the engine with the greater stroke will have more low end grunt. Think of a bicycle. Your legs are the piston, the "WAM"! but the length of which the pedal is attached (crank) would be your stroke. A little less leg can out perform if the crank of which the pedal is attached is much longer. Maybe the person x crank would be less than but torque could be greater than. There, lol.....

Motor: noun, a machine, especially one powered by electricity or internal combustion , that supplies motive power for a vehicle or for another device with moving parts.

I don't know what universe you live in, but to me comparing a diesel engine and a gasoline engine is NOT equal :banghead:

Also, if you have two identical motors and you change the bore to stroke ratio in one of them, they are no longer equal proportionate to displacement

A stoichiometric amount or stoichiometric ratio of a reagent is the optimum amount or ratio where, assuming that the reaction proceeds to completion:

  1. All of the reagent is consumed
  2. There is no deficiency of the reagent
  3. There is no excess of the reagent.
This means all of the fuel is burnt in the combustion process.

Regarding stoich and EGR, nice try but it doesn't take a genius to work out that most automobile engines don't operate at full throttle 100% of the time, as a result the mixture isn't at stoich 100% of the time.

Stoich for gasoline is 14.7:1 AFR
part throttle should be somewhere near 12.5:1 AFR, though it's highly application specific.

Now given that 14.7:1 is the optimum air fuel ratio for burning every single unit of oxygen in the chamber, at 12.5:1 (which is richer) there is obviously going to be higher exhaust emissions due to unburnt fuel and air. This and this alone necessitates an EGR system to reduce emissions.

Again, everything being equal and proportionate to displacement a motor with a larger displacement will undoubtedly produce more torque.
 
Again, everything being equal and proportionate to displacement a motor with a larger displacement will undoubtedly produce more torque.

Torque is a rather meaningless number on its own just like rpm, but rpm is equally important of a number as torque.

If I said I had two engines that made 300lbs-ft it really tells you nothing about the engines or its ability to perform.
Same as rpm if I said one makes peak torque at 3000 rpm and the other 6000 rpm which also tells you nothing, that's why they invented HP.
If I told you one engine made 171 HP and told you the other made 342 HP you would know engine 2 could do twice the work no matter the the torque or rpm numbers.

300lbs-ft X 3000 rpm / 5252 = 171 HP
300lbs-ft X 6000 rpm / 5252 = 342 HP
 
If you want a 340, get a 340. If you want a 360, get a 360. Everything else is just stupid.
 
If you want a 340, get a 340. If you want a 360, get a 360. Everything else is just stupid.

Right, Rob! But sometimes stupid is fun...... lol. Frosty and myself are so far off subject that neither one of us are on this threads universe, but I have had a good laugh........ See, he wants to know what universe I'm on, well, I'll tell him. It's the same on he is on!! lol. Think anyone has gotten anything from the garbage we post.....NOOOOOOOOOOOOPE! :D
 
Torque is a rather meaningless number on its own just like rpm, but rpm is equally important of a number as torque.

If I said I had two engines that made 300lbs-ft it really tells you nothing about the engines or its ability to perform.
Same as rpm if I said one makes peak torque at 3000 rpm and the other 6000 rpm which also tells you nothing, that's why they invented HP.
If I told you one engine made 171 HP and told you the other made 342 HP you would know engine 2 could do twice the work no matter the the torque or rpm numbers.

300lbs-ft X 3000 rpm / 5252 = 171 HP
300lbs-ft X 6000 rpm / 5252 = 342 HP

But 342 HP in your example accelerates at exactly the same rate as 171hp because they both have the same force being applied, torque. More torque equals more force equals more acceleration. More horsepower does not necessarily equal for force, just the same force spinning at a higher rpm. Now all of this is just taking a single moment in time. What really matters is how broad that torque curve is made. Here is where the high HP number means something, if the motor make that torque early and held it all the way to high rpms, then you can also take advantage of lower gearing to multiply the torque. Its still all about torque, HP cannot even be measured independently, its a mathematical derivative of torque, acceleration is only a factor of torque.
 
You're traveling through another dimension, a dimension not only of sight and sound but of mind; a journey into a wondrous land whose boundaries are that of imagination. Your next stop...the Twilight Zone.
 
But 342 HP in your example accelerates at exactly the same rate as 171hp because they both have the same force being applied, torque. More torque equals more force equals more acceleration. More horsepower does not necessarily equal for force, just the same force spinning at a higher rpm..

Torque doesn't accelerate the car alone its Torque X Rpm that does which is HP. Which is the definition of horsepower is to move Weight over a Distance in a certain amount of Time, EG... accelerate a car (weight) over a 1/4 mile (distance) in a E.T. (certain amount of time). If torque only mattered then they wouldn't of needed to come up with horsepower ratings, rpm is an equal force to torque, without either your car is going nowhere.

Its still all about torque, HP cannot even be measured independently, its a mathematical derivative of torque, acceleration is only a factor of torque.

Again its Torque X RPM
 
Right, Rob! But sometimes stupid is fun...... lol. Frosty and myself are so far off subject that neither one of us are on this threads universe, but I have had a good laugh........ See, he wants to know what universe I'm on, well, I'll tell him. It's the same on he is on!! lol. Think anyone has gotten anything from the garbage we post.....NOOOOOOOOOOOOPE! :D

I got what you we're originally trying to say
if you we're to build let say a 400 hp 318 and 340 and build the 318 more efficiently you could possibly make the same HP at the same RPM. I think a well put together 318 could close the gap a bit but I don't think it could do the same RPM cause basically your using the same parts but the smaller bore would help.
 
No, it's torque x horse power / bullshit - hooah to the third power over blah blah blah.
 
and why haven't you guys been discussing torque transfer.
torque/rpm as speed increases
 
because then they might start getting into parasitic losses and that might just tip the advantage to...

...I drank what?
 
Torque doesn't accelerate the car alone its Torque X Rpm that does which is HP. Which is the definition of horsepower is to move Weight over a Distance in a certain amount of Time, EG... accelerate a car (weight) over a 1/4 mile (distance) in a E.T. (certain amount of time). If torque only mattered then they wouldn't of needed to come up with horsepower ratings, rpm is an equal force to torque, without either your car is going nowhere.



Again its Torque X RPM

Say for a minute you had a motor that had a perfectly flat torque curve from 1000 rpm to 6000 rpm and stays in the same gear. Discounting wind resistance the car will accelerate at a constant rate all though 1000-6000rpm because the torque is what is working. Yet the car is making 6 times as much HP at 6000 rpm it isn't accelerating any faster then it is at 1000 rpm.
 
If you were in Australia I can tell the biggest difference between 340 and 360 is $$.

They are asking over $3,000!!! for rebuilder 340s
where you can get a similar 360 for $700 or less.
 
340 or 360? your choice, can't go wrong with either one. but, I will stick with 383.
we have built many over the past 35 years. they are bulletproof!
 
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