help me understand torque and hp

[ShawnD1]

Not true. The torque at the wheels is what accelerates the car. If the engine makes the same horsepower at higher RPM with less torque, gear it shorter, and the car doesn't know the difference.

You can put a truck diesel engine with 1000ftlb in a car, but the low RPM makes it necessary to gear it up so the car doesn't accelerate any faster than a lower torque gas engine.

Stop trying to explain how it actually works and start explaining how some people wish it worked. That way we could totally convince people to buy high efficiency cars with 80HP diesel engines just because "But bro, it has 150ft-lb of torque. That's more than a Honda Civic or Ford Focus!!"

If you want more torque in your car and don't care too much about power, get a steam engine. Those things are all torque, no power.

 

[ShawnD1]

What's wrong with this thread is the armchair mechanics. WTF is "full torque"?. And no shit a "civic engine" doesn't have the same torque as a "truck engine". It's called: displacement.

Shawn, go away.

Quotin' dis because it's by far the most retarded thing anyone has ever said in the history of ATG.

2.5L Subaru STI - 290 lb-ft torque
4.0L Ford Ranger - 238 lb-ft torque

So much for your fleabag theories. Go back to your troll cave.

 

[Bartman39]

Quotin' dis because it's by far the most retarded thing anyone has ever said in the history of ATG.

2.5L Subaru STI - 290 lb-ft torque
4.0L Ford Ranger - 238 lb-ft torque

So much for your fleabag theories. Go back to your troll cave.

ShawnD1 have you lost your mind again...? Do you not realize the STI is turbo charged...? Put a turbo on the 4.0L and once again out the door you go...? This is what makes you look ...?

Apples and Oranges dood...? I think you do alot of good thinking but it gets misplaced somehow or another...?

 

[Howard]

Not true. The torque at the wheels is what accelerates the car.

Was this really necessary? You are contradicting that torque accelerates the car?

 

[ShawnD1]

ShawnD1 have you lost your mind again...? Do you not realize the STI is turbo charged...? Put a turbo on the 4.0L and once again out the door you go...? This is what makes you look ...?

Apples and Oranges dood...? I think you do alot of good thinking but it gets misplaced somehow or another...?

Fine then take the turbo out of the equation.

3.5L Ford Fusion - 249 lb-ft torque
4.0L Ford Ranger - 238 lb-ft torque

Both are naturally aspirated, both are Ford, both are model year 2011. Why does the smaller engine have more torque? Come on, I know you know this. Don't let me down.

 

[Bartman39]

Fine then take the turbo out of the equation.

3.5L Ford Fusion - 249 lb-ft torque
4.0L Ford Ranger - 238 lb-ft torque

Both are naturally aspirated, both are Ford, both are model year 2011. Why does the smaller engine have more torque? Come on, I know you know this. Don't let me down.

11ft-lbs and only .5 liter less (very little difference)... Still pretty close even considering the 3.5 liter has 24 valves compared to the 4.0 older tech 12 valve design which is also a pushrod engine as compared to the overhead cam design of the Fusion engine...

Why do you think GM got away from the 16 valve 6.5 liter turbo in the trucks (besides being an illfated design) then going with a 32 valve 6.6 turbo diesel...? Still using the same basic engine for 10+ years now and tons of them out there producing over 500HP & 1000+ ftlbs of TQ too and are every day drivers...

 

[ShawnD1]

11ft-lbs and only .5 liter less (very little difference)... Still pretty close even considering the 3.5 liter has 24 valves compared to the 4.0 older tech 12 valve design which is also a pushrod engine as compared to the overhead cam design of the Fusion engine...

Now you're getting it. It has everything to do with engine design. Truck engines are very different from car engines. That Ford Ranger hits max torque around 3000rpm while the Fusion is up in the 4000s. Trucks also have weird redline rpm. The 4 cylinder Tacoma redlines at only 5200rpm.

Saying it's just displace is retarded.

 

[exdeath]

But you dont necessarily want 700 torque and 700 horsepower... For example, an f1 engine has a measly 200 torque, but 800 hp.

Why not? If you think that F1 engine is great, imagine if it put out 800 lb-ft off idle and still delivered peak 800 HP?

 

[exdeath]

Poor phrasing on your part as you did not properly isolate from the prep phrase.

"700 peak horsepower along with 700lb-ft from 2000RPM to redline." would've been better, which puts your redline at 5252RPM.

You're an idiot. How did you determine that redline?

 

[punjabiplaya]

You're an idiot. How did you determine that redline?

"fuzzy math"

 

[Bartman39]

Now you're getting it. It has everything to do with engine design. Truck engines are very different from car engines. That Ford Ranger hits max torque around 3000rpm while the Fusion is up in the 4000s. Trucks also have weird redline rpm. The 4 cylinder Tacoma redlines at only 5200rpm.

Saying it's just displace is retarded.

ShawnD1 now you cant just say truck engines and car engines are very different... GM uses the same 5.3 liter from the trucks in some of the cars and the basic design from 4.8 liter to 6.2 liter is the same just suttle changes to bore & stroke with piston design changes and of course cam profiles and head designs but all based on the same basic centerlines & 6 bolt mains with alum heads... Truck engines are setup to produce TQ at lower RPM`s for towing and heavy hauling where as a car is not designed for this type labor... Different auto makers use their own combinations for various reasons due to tooling and tried and true well proven combinations... Some change them for reasons unknown which is in my book kinda dumb but hey we are at their mercy...


Hey exdeath you ended up qouting what I said about him too (DominionSeraph)...:thumbsup:

 

[Throckmorton]

Was this really necessary? You are contradicting that torque accelerates the car?

I'm saying that acceleration rate depends on torque at the wheels, not at the engine. That depends on gearing and engine torque.

You can have a diesel engine that puts out twice the peak torque of an equivalent gas engine, but it also has a much lower redline. Once you gear it appropriately, it's not going to be faster just because the peak torque is higher.

There are gas turbine powered tanks. Even though a gas turbine puts out much lower torque than a piston engine doesn't mean tanks are gutless... Because they spin much faster and the transmission is geared appropriately for a gas turbine.

There are propeller planes powered by gas turbines, wankels, and diesels. Each type is geared appropriately to get the propeller spinning at the right speed. A diesel airplane isn't the fastest just because diesel torque output is the highest.

 

[punjabiplaya]

remember the Space shuttle has 1million whatever horsepower

and 0 torque

 

[Bartman39]

remember the Space shuttle has 1million whatever horsepower

and 0 torque

Cause it aint got no wheels (except during landing)...:biggrin:

 

[punjabiplaya]

Cause it aint got no wheels (except during landing)...:biggrin:

nah, cuz it's a Honda
VTEC YO

lol but seriously, no rotation = no torque

you can have torque with no wheels easily

|-----0-----|

two rockets pushing in opposite directions around a joint

 

[exdeath]

|-----0-----|

two rockets pushing in opposite directions around a joint

Ain't got shit on Chuck Norris. His hands around one of your joints moving in opposite directions produces an estimated 10,000,000,000 lb-ft of torque, but there is no machine on Earth capable of measuring it.

 

[punjabiplaya]

Ain't got shit on Chuck Norris. His hands around one of your joints moving in opposite directions produces an estimated 10,000,000,000 lb-ft of torque, but there is no machine on Earth capable of measuring it.

<insert Chuck Norris on a dyno joke>

 

[PlasmaBomb]

Ain't got shit on Chuck Norris. His hands around one of your joints moving in opposite directions produces an estimated 10,000,000,000 lb-ft of torque, but there is no machine on Earth capable of measuring it.

<insert Chuck Norris on a dyno joke>

??

Exdeath already did it...

 

[punjabiplaya]

??

Exdeath already did it...

yeah I was referring to it as the gratuitous Chuck Norris on a dyno joke

 

[arcenite]

Fine then take the turbo out of the equation.

3.5L Ford Fusion - 249 lb-ft torque
4.0L Ford Ranger - 238 lb-ft torque

Both are naturally aspirated, both are Ford, both are model year 2011. Why does the smaller engine have more torque? Come on, I know you know this. Don't let me down.

It's half a liter and 11 ft-lbs. And at what RPM? It is just displacement, of course there are always exceptions to the rule. Is the 3.5L running full torque all the time?

Edit: And you calling me a troll is marvelous.

 

[Throckmorton]

Fine then take the turbo out of the equation.

3.5L Ford Fusion - 249 lb-ft torque
4.0L Ford Ranger - 238 lb-ft torque

Both are naturally aspirated, both are Ford, both are model year 2011. Why does the smaller engine have more torque? Come on, I know you know this. Don't let me down.

The Fusion 3.5L is a better engine. The 4.0L in the Ranger is the old Windsor V6 that dates back to the 1960s.

 

[DominionSeraph]

How did you determine that redline?

Duh. If you've got a flat torque curve of 700lb-ft then you can't be making it above 5252RPM or you'd be making more than 700 peak horsepower.

700 peak HP with flat 700lb-ft means a 5252RPM redline. You'd need the torque to drop off below 700lb-ft (which contradicts the "flat") to go above 5252RPM and not blow past 700HP.

You're an idiot.

I'm not the one having difficulties with 6th grade algebra.

 

[DominionSeraph]

Now I realize your not just an idiot..

"you're"

Dont screw with exdeath he could pull 3 plug wires off his Stang and still "torque twist" your little rice ride in to Saki...

"Don't"
"exdeath,"
"'stang"
"into"
"sake"

Jesus.

Hey exdeath you ended up qouting what I said about him too (DominionSeraph)...:thumbsup:

Exdeath can at least write.

Also:
"Hey,"
"exdeath,"
"quoting"
"him,"
"too."

 

[Bartman39]

DominionSeraph...

Oh I`m so sorry I must bow down to you and your great uh (colorful metaphor)...? While you may know how to write and be book smart it does not change the fact that you know nothing of what people mean when they say something other than you are an ass and think by looking down your nose at them it makes you look semi-intelligent... You can turn a page in a book but really doubt you could even consider knowing how to turn a wrench other than to screw somthing up from what you have posted so far...

So a word of advise is to either contribute something positive and quit being a grammar queer or just move over to "off topic" and get your ass handed to you, there are plenty over there that can do it... I dont care or have time for your BS so its your option to continue to be an idiot or use what you have to be a postive contributor...

"A true idiot can be ignored"

If your really smart you`ll know who said this...

 

[exdeath]

Duh. If you've got a flat torque curve of 700lb-ft then you can't be making it above 5252RPM or you'd be making more than 700 peak horsepower.

700 peak HP with flat 700lb-ft means a 5252RPM redline. You'd need the torque to drop off below 700lb-ft (which contradicts the "flat") to go above 5252RPM and not blow past 700HP.



I'm not the one having difficulties with 6th grade algebra.

And again you're being an ass. Dyno graphs are approximate, not numerically algebraically perfect. Nothing that anybody here would call "flat" is truly numerically constant to begin with. I also never said anything about not going above 700 HP or exactly 700 HP either. An engine that produces 701 HP at 5253 RPM is still a "700 HP engine" to anyone who cares.

The real life engine in question would be 624 HP / 601 lb-ft at the wheels. This is an example of an engine that *approximately* produces *both* ~700+ at high RPM and ~700+ lb-ft at low RPM. The target audience, car enthusiasts, knows exactly what I mean without getting into semantics pissing contests.


You're trying too hard to look smart.