Back in the late 80's when Dodge started using the Cummins Turbo Diesel in their trucks as an optional engine, it only made 160 HP.
But get this, the torque was 400 lb ft!! And it made that peak torque at less than 2000 rpm. Talk about an easy stick shift vehicle to drive, how could you kill it with that much torque?
The engine has been improved over the years and now makes 235 HP and 450 lb ft of torque. That's a real engine. If you put that sucker into an Integra, the motor would squish the whole car like a grape. But if you want to go fast, you need that high revving motor. Just keep in mind that if 2 motors have the same torque, but one engine makes it's torque at twice the engine speed as the other, it will have double the horsepower. As others have said, horsepower is a function of torque and engine speed, but torque is torque. It's the independent variable.
PG
But get this, the torque was 400 lb ft!! And it made that peak torque at less than 2000 rpm. Talk about an easy stick shift vehicle to drive, how could you kill it with that much torque?
The engine has been improved over the years and now makes 235 HP and 450 lb ft of torque. That's a real engine. If you put that sucker into an Integra, the motor would squish the whole car like a grape. But if you want to go fast, you need that high revving motor. Just keep in mind that if 2 motors have the same torque, but one engine makes it's torque at twice the engine speed as the other, it will have double the horsepower. As others have said, horsepower is a function of torque and engine speed, but torque is torque. It's the independent variable.
PG
PW assuming:
350lb/f torque @ 2500rpm then 250hp.
350lb/f torque @ 5000rpm then 500hp?
I dunno...maybe though...
350lb/f torque @ 2500rpm then 250hp.
350lb/f torque @ 5000rpm then 500hp?
I dunno...maybe though...
Genocide, it really depends on what use that honda engine was designed to fit in. Generaly honda and most japanese car motors have to meet a certain fuel efficiency and liter size requirement. These requirements are met by characteristics favored by smaller (fuel economy) higher reving (to have decent hp)engines that consequently will have lower torque numbers. American V-8's by design are crude motors that compensate sheer liter size for lack of efficiency. This is done to meet their primary design goal, low cost. You'll notice that honda engines found in 4door cars and vans will have higher displacement, lower rpm limits, but higher torque at lower rpms than their sport counterparts. Bottom line is a good engine is built from the ground up to fit it's design needs, honda or otherwise.
NFS4
No Lifer
- Oct 9, 1999
- 72,636
- 47
- 91
<< American V-8's by design are crude motors that compensate sheer liter size for lack of efficiency. >>
What about the 3.9 liter DOHC V8 in the Lincoln LS or the Cadillac Northstar series...the Mustangs also have efficient, high-tech DOHC V8's. Same goes for the Expedition and Navigator. And don't leave out the sweet 4.7 liter SOHC V8 in the Grand Cherokee.
Got a 66 Malibu with a 454. And frankly, If I lost the 500ft.lbs torque it's pumping out... well, I really wouldnt have as much fun.
Horse is good, just build the engine to your needs. This car is great, but it's a bitch in the rain sometimes. Or is it a helluva lot of fun in the rain sometimes...
Ah well, least it doesnt sound like a sick lawnmower.
Horse is good, just build the engine to your needs. This car is great, but it's a bitch in the rain sometimes. Or is it a helluva lot of fun in the rain sometimes...
Ah well, least it doesnt sound like a sick lawnmower.
Getting torque and HP outta a Toyota? send it to the crusher and buy a Mustang, taht is the fastest way
PG, you lost me here.... enlighten me, you said..
"Just keep in mind that if 2 motors have the same torque, but one engine makes it's torque at twice the engine speed as the other, it will have double the horsepower. As others have said, horsepower is a function of torque and engine speed, but torque is torque. It's the independent variable. "
You'll have to carify what the specs are and what exactly you mean. Simply spinning a motor at twice the rpms will not net you twice the horsepower. Horsepower is not a function of torque and engine speed, horsepower is the total amount of work an engine is capable of. I could build two engines with the same displacement and the same max hp. They'll both be able to do the same amount of work but can have different max torque figures. I do agree that if you have hp you MUST have torque. But you must enlighten me one how horsepower is a function of torque AND engine speed. My understanding is that torque is generated by the total amount of air/fuel you are burning, the length of the connecting rod and the length of the stroke of the crankshaft. How does engine rpm factor greatly in the amount of torque generated?
"Just keep in mind that if 2 motors have the same torque, but one engine makes it's torque at twice the engine speed as the other, it will have double the horsepower. As others have said, horsepower is a function of torque and engine speed, but torque is torque. It's the independent variable. "
You'll have to carify what the specs are and what exactly you mean. Simply spinning a motor at twice the rpms will not net you twice the horsepower. Horsepower is not a function of torque and engine speed, horsepower is the total amount of work an engine is capable of. I could build two engines with the same displacement and the same max hp. They'll both be able to do the same amount of work but can have different max torque figures. I do agree that if you have hp you MUST have torque. But you must enlighten me one how horsepower is a function of torque AND engine speed. My understanding is that torque is generated by the total amount of air/fuel you are burning, the length of the connecting rod and the length of the stroke of the crankshaft. How does engine rpm factor greatly in the amount of torque generated?
PG the post you had about a cummings TURBO DIESEL, I'll try to explain how it generates those numbers and how it will not do well in an integra. First off you're right, the sheer size and weight of that engine would probably squish the integra. A gasolene motor has a compression ratio usualy around 8.0 to 1 and that goes up with higher performance motors. A diesel engine runs on basicly oil (diesel fuel)it does not vaporize readily and so it does not burn as efficiently as gasoline. In fact for diesel engines to even run the compression ratio has to be much higher than gasoline engines, it's about 22 to 1. The high compression ratio of diesel engines is one reason it generates so much torque. You have the stored energy from a 22 to 1 compression ratio in addition to the energy from the burned fuel pushing down on that piston. Another reason is the design specs of it's requirement. Diesel engines are usualy in commercial use where longevity is the prime design goal. The lower rpm that engines run in general the longer they will last. So they longer stroke cranks in diesels to increase torque as compensation for it's low rpm design goal. They don't have a lot of torque because it's running low rpms but because if the longer stroke.
NFS4 the hp/liter ratio of the integra GSR engine is 100hp per liter. Does the lincon LS or cadilac northstar have 390hp? does the Cherokee V-8 have 470hp?? By american car standards the cadilac and others are "high efficiency" and "high-tech" but they are nowhere near the efficiency acheived by the integra GSR motor. Let's take the honda accord... if memory serves me right it's a 2.2 liter motor with 160hp that 72.7hp per liter. If the Cherokee motor at 4.7 liters had the same efficiency it should have 341hp. We both know that the Jeep Cherokee does NOT have 341hp. So the jeep cherokee does not even have the same efficiency as a run of the mill honda accord. I'm not saying that the jeep cherokee motor is a bad motor, but it does have different design goals and has advantages in different areas. But I will say that calling the cherokee motor a "high efficiency" or "high tech" motor would be like calling a cow a fast and agile animal. A cheatah is fast, a gazelle is fast a cow is not fast.
NFS4
No Lifer
- Oct 9, 1999
- 72,636
- 47
- 91
eia430, it's easy to make a four banger efficient...forget that comparison b/c it just doesn't work. Comparing the efficiency of a four-banger to that of a V8 is like comparing apples to oranges.
For a more direct comparison, take the 4.7 liter SOHC V8 in the Grand Cherokee/Dakota/Durango and compare it to the 4.7 DOHC V8 in the Toyota Tundra/Sequoia.
Dodge V8 SOHC engine - 235HP/295lb-ft
Toyota V8 DOHC engine - 245HP/315lb-ft
The Dodge is quite efficient I must say and with DOHC, it would most likely match the Toyota's numbers. But I would by no means call it a "brutish" engine.
How you like dem apples?
For a more direct comparison, take the 4.7 liter SOHC V8 in the Grand Cherokee/Dakota/Durango and compare it to the 4.7 DOHC V8 in the Toyota Tundra/Sequoia.
Dodge V8 SOHC engine - 235HP/295lb-ft
Toyota V8 DOHC engine - 245HP/315lb-ft
The Dodge is quite efficient I must say and with DOHC, it would most likely match the Toyota's numbers. But I would by no means call it a "brutish" engine.
How you like dem apples?
eia430,
Torque*RPM/5252=Horsepower
Thus if one motor is producing 300lb.-ft. @ 3000RPM, it is producing 171HP at that engine speed. If a second motor is producing the same 300lb.-ft. but @ 6000RPM it will produce 343HP again, at that engine speed. It should be noted that this does not mean the second motor necessarily produces more horsepower, as the first motor may still be climbing in torque output beyond 3000RPM.
An engine making it's peak torque at any RPM below 5252 will ALWAYS make more torque than HP, and an engine making it's peak torque above 5252 will ALWAYS make more HP than torque. Think of it this way...torque is how hard you're working, RPM is how often you do your work, HP is how much work you can get done in a given time.
One last thing, torque has no direct relation to size of bore and length of stoke, or amount of air/fuel being consumed (meaning you can't just figure out torque output by knowing those variables). However, it is fairly common knowledge that an oversquare motor (larger bore than stroke) tends to produce higher revving, "peaky" motors. Conversely, an undersquare motor (longer stroke than bore) will produce a more smooth and tractable style of output. All other things being equal of course.
Torque*RPM/5252=Horsepower
Thus if one motor is producing 300lb.-ft. @ 3000RPM, it is producing 171HP at that engine speed. If a second motor is producing the same 300lb.-ft. but @ 6000RPM it will produce 343HP again, at that engine speed. It should be noted that this does not mean the second motor necessarily produces more horsepower, as the first motor may still be climbing in torque output beyond 3000RPM.
An engine making it's peak torque at any RPM below 5252 will ALWAYS make more torque than HP, and an engine making it's peak torque above 5252 will ALWAYS make more HP than torque. Think of it this way...torque is how hard you're working, RPM is how often you do your work, HP is how much work you can get done in a given time.
One last thing, torque has no direct relation to size of bore and length of stoke, or amount of air/fuel being consumed (meaning you can't just figure out torque output by knowing those variables). However, it is fairly common knowledge that an oversquare motor (larger bore than stroke) tends to produce higher revving, "peaky" motors. Conversely, an undersquare motor (longer stroke than bore) will produce a more smooth and tractable style of output. All other things being equal of course.
No NFS4 you compared apples and oranges not I.... I was talking about the GSR engine. You were the one that made the comparason to the lincon, the mustang, the cadilac and the cherokee. I merely addressed your comparison. And besides we are not talking about who makes the better truck or the better car, we are discussing engine efficiency and hp/torque.
NFS4
No Lifer
- Oct 9, 1999
- 72,636
- 47
- 91
<< No NFS4 you compared apples and oranges not I.... I was talking about the GSR engine. >>
No, you are getting confused
You said this:<< American V-8's by design are crude motors that compensate sheer liter size for lack of efficiency >>
And I responded with this:
<< What about the 3.9 liter DOHC V8 in the Lincoln LS or the Cadillac Northstar series...the Mustangs also have efficient, high-tech DOHC V8's. Same goes for the Expedition and Navigator. And don't leave out the sweet 4.7 liter SOHC V8 in the Grand Cherokee. >>
How the GSR got into the subject, I don't know. I have been talking about V8's the whole time...you're the one that got off on a tangent coparing V8's to four-bangers which isn't really fair IMHO. I then responded with my post about the Dodge and Toyota V8's since that is a more fair comparison giving the engine size and type of engine. All of my points addressed to you have been about V8's.
YBS1 you said...
"Torque*RPM/5252=Horsepower Thus if one motor is producing 300lb.-ft. @ 3000RPM, it is producing 171HP at that engine speed. If a second motor is producing the same 300lb.-ft. but @ 6000RPM it will produce 343HP again, at that engine speed. It should be noted that this does not mean the second motor necessarily produces more horsepower, as the first motor may still be climbing in torque output beyond 3000RPM. An engine making it's peak torque at any RPM below 5252 will ALWAYS make more torque than HP, and an engine making it's peak torque above 5252 will ALWAYS make more HP than torque. Think of it this way...torque is how hard you're working, RPM is how often you do your work, HP is how much work you can get done in a given time. One last thing, torque has no direct relation to size of bore and length of stoke, or amount of air/fuel being consumed (meaning you can't just figure out torque output by knowing those variables). However, it is fairly common knowledge that an oversquare motor (larger bore than stroke) tends to produce higher revving, "peaky" motors. Conversely, an undersquare motor (longer stroke than bore) will produce a more smooth and tractable style of output. All other things being equal of course. "
I spent quite a few years building motors from the ground up to develop horsepower, torque and other requirements. I've adjusted everything from valve size, intake port shape/angle of entry, camshaft timing/lift/lobe geometry, crankshaft stroke length, bore size, etc, etc, etc. I am quite familliar with what general effects each adjustment makes. I highly suggest you go to your local Bookstar or Barns & Noble and read up on engine building. I'm sure you will find those books informative and quite surprising.
After reading your above post, it is patently obvious that you need to buildup your basic engine principles knowledge first. Your last post just told me that the world is flat, all the planets in the heavens revolve around the earth and that the best way to cure a sick and dying man is to bleed him to "drain the impurities away." I just don't know how to reply to those things.
"Torque*RPM/5252=Horsepower Thus if one motor is producing 300lb.-ft. @ 3000RPM, it is producing 171HP at that engine speed. If a second motor is producing the same 300lb.-ft. but @ 6000RPM it will produce 343HP again, at that engine speed. It should be noted that this does not mean the second motor necessarily produces more horsepower, as the first motor may still be climbing in torque output beyond 3000RPM. An engine making it's peak torque at any RPM below 5252 will ALWAYS make more torque than HP, and an engine making it's peak torque above 5252 will ALWAYS make more HP than torque. Think of it this way...torque is how hard you're working, RPM is how often you do your work, HP is how much work you can get done in a given time. One last thing, torque has no direct relation to size of bore and length of stoke, or amount of air/fuel being consumed (meaning you can't just figure out torque output by knowing those variables). However, it is fairly common knowledge that an oversquare motor (larger bore than stroke) tends to produce higher revving, "peaky" motors. Conversely, an undersquare motor (longer stroke than bore) will produce a more smooth and tractable style of output. All other things being equal of course. "
I spent quite a few years building motors from the ground up to develop horsepower, torque and other requirements. I've adjusted everything from valve size, intake port shape/angle of entry, camshaft timing/lift/lobe geometry, crankshaft stroke length, bore size, etc, etc, etc. I am quite familliar with what general effects each adjustment makes. I highly suggest you go to your local Bookstar or Barns & Noble and read up on engine building. I'm sure you will find those books informative and quite surprising.
After reading your above post, it is patently obvious that you need to buildup your basic engine principles knowledge first. Your last post just told me that the world is flat, all the planets in the heavens revolve around the earth and that the best way to cure a sick and dying man is to bleed him to "drain the impurities away." I just don't know how to reply to those things.
NFS4 you are right.... I did post that, My intention was to say all american motors in general... I had no intention to say just v-8s because even the american 4 bangers tended to be larger to develop the same hp as their japanese counterparts. How that V-8 got stuck there must have been a brain fart of my part. The point I was trying to make is that American car manufacturers chose the club rather then the scalpel method of gaining horsepower. It's cheap first quality second. Only the vast hemmoraging of sales to japanese cars that convinced american car makers that if you put out crap for a product people won't buy it. Now they are playing catch up to the japanese.
eia430:
<< . To survive at that rpm they had to give it a very short stroke to reduce piston speed enough so it won't fly apart. Reducing the stroke of the crankshaft reduces the mechanical advantage of the engine reducing it's torque. >>
Interesting stuff.. Never really think too much on how the stroke will affect engine output.
So what kind of engines do you build?? What company do you work for??
As far as American Engine vs. Euro/Japanese Engine, this is what I think:
American can make good engines, they have the technology to do it. But if they see the need to do so. Look at the C5 and the Z06. Nice engines. For the majority though, americans do prefer larger displacement engines. Simply for cost reasons, I believe. Why would you want a hi-tech engine in your SUVs, Taurus, Caprice, Lincoln, or Neon??
Japan is different. They can't afford driving a 5 liter camaro. 1 reason being GAS prices, 2nd reason tax (maybe). So, they take a 2 liter engine, put DOHC, VTEC, whatever, Turbo to get the most out of it. Another reason is the size of the car. Their average sedan (Accord) is far smaller and lighter to the average american 4 doors (taurus as example). Thus you don't really need the torque that you can only get from larger displacement. They don't make trucks, and they don't make SUVs (until recently). What do you need the large displacement for?? 4 liter engine in an Integra will only mess up its balance.
I think the Europeans have similar reasoning for their engines. GAS prices. Tax (for Britain, at least). But we do see european manufacturer make bigger engines (BMW's 540, Merc's E55) once in a while.
Industries today are based on customer demand. That's why Americans build a different type of engines than the Japanese/European. I often hear hear people say "america is so behind in technology, look at their engines".. What an idiot.
<< . To survive at that rpm they had to give it a very short stroke to reduce piston speed enough so it won't fly apart. Reducing the stroke of the crankshaft reduces the mechanical advantage of the engine reducing it's torque. >>
Interesting stuff.. Never really think too much on how the stroke will affect engine output.
So what kind of engines do you build?? What company do you work for??
As far as American Engine vs. Euro/Japanese Engine, this is what I think:
American can make good engines, they have the technology to do it. But if they see the need to do so. Look at the C5 and the Z06. Nice engines. For the majority though, americans do prefer larger displacement engines. Simply for cost reasons, I believe. Why would you want a hi-tech engine in your SUVs, Taurus, Caprice, Lincoln, or Neon??
Japan is different. They can't afford driving a 5 liter camaro. 1 reason being GAS prices, 2nd reason tax (maybe). So, they take a 2 liter engine, put DOHC, VTEC, whatever, Turbo to get the most out of it. Another reason is the size of the car. Their average sedan (Accord) is far smaller and lighter to the average american 4 doors (taurus as example). Thus you don't really need the torque that you can only get from larger displacement. They don't make trucks, and they don't make SUVs (until recently). What do you need the large displacement for?? 4 liter engine in an Integra will only mess up its balance.
I think the Europeans have similar reasoning for their engines. GAS prices. Tax (for Britain, at least). But we do see european manufacturer make bigger engines (BMW's 540, Merc's E55) once in a while.
Industries today are based on customer demand. That's why Americans build a different type of engines than the Japanese/European. I often hear hear people say "america is so behind in technology, look at their engines".. What an idiot.
I like my Olds Intrigue
215HP and 230ftlbs Torque
DOHC motor, so it accelerates at an increasing level as the RPM's go up.
At about 3500RPM, man does that thing hit it's song.
Perfectly matched for 2-lane highway driving...feels like 60 - 85MPH in about 3 sec
215HP and 230ftlbs Torque
DOHC motor, so it accelerates at an increasing level as the RPM's go up.
At about 3500RPM, man does that thing hit it's song.
Perfectly matched for 2-lane highway driving...feels like 60 - 85MPH in about 3 sec
Fact is 90% of the time when you are on the road you are riding on the torgue not the horsepower - if you were to ask any fuel injection tuner what the analyse of your driving pattern was after he plugged his lap-top into your wiring harness, the odds are you would have only rev past 4K less than about 5 or 10% of the time while driving.
Consquently its best to have your 'good power' in that 1500 to 3500 rev band where most people do most of their driving, & that's what torque is all about - why do you think that Cam regrind companies sell 'Taxi pak' cams, that actually make your engines less of a rever, its because you get better torque & efficiency in that power band that you do most of your driving in (1500 to 3500 revs).
Consquently its best to have your 'good power' in that 1500 to 3500 rev band where most people do most of their driving, & that's what torque is all about - why do you think that Cam regrind companies sell 'Taxi pak' cams, that actually make your engines less of a rever, its because you get better torque & efficiency in that power band that you do most of your driving in (1500 to 3500 revs).
Lupin, I can't really discuss the company I worked with. My ex-partner chose to do quite a few underhanded things to customers. I have spoken to those customers and explained the situation and they thankfuly have kept me out of their action. But it is best for me to not discuss the matter. This was many years back but why take the chance.
For your second question of what engines I worked on. I specialized in japanese cars, hondas in particular. I did everything from simple air filter/exhaust upgrades to turbocharger installs, to complete engine teardown and upgrade everything including the ECU (I used tec II)
For your other comments, I agree with you. I fully realize that the inferiority of american engines and cars does is not for lack of know how or lack of technology. It is because of the fat bloated pigs called management that have decided to skimp everywhere they could. Even if it means putting out inferior work with planned obselecence. Their primary goal is the bottom line(profits) and the simple truth is the more corners they cut the fatter their wallets. Only during the early to mid 90's did management start taking steps to improve the quality of american cars. They were forced to do so because people were buying japanese cars in droves. There were more people (non government retail sales) buying the toyota camery than any other car period. Including the cheap ford escort. This was when american car companies realized improve or die.
For your second question of what engines I worked on. I specialized in japanese cars, hondas in particular. I did everything from simple air filter/exhaust upgrades to turbocharger installs, to complete engine teardown and upgrade everything including the ECU (I used tec II)
For your other comments, I agree with you. I fully realize that the inferiority of american engines and cars does is not for lack of know how or lack of technology. It is because of the fat bloated pigs called management that have decided to skimp everywhere they could. Even if it means putting out inferior work with planned obselecence. Their primary goal is the bottom line(profits) and the simple truth is the more corners they cut the fatter their wallets. Only during the early to mid 90's did management start taking steps to improve the quality of american cars. They were forced to do so because people were buying japanese cars in droves. There were more people (non government retail sales) buying the toyota camery than any other car period. Including the cheap ford escort. This was when american car companies realized improve or die.
debanchee, yep, it's called designing for intended use. When people talk about this engine being better than that engine they probably are overlooking that it might work perfectly for it's INTENDED use.
eia430, You went to the trouble of quoting my entire post yet failed to comment about anything in it being inaccurate. You stated "Simply spinning a motor at twice the rpms will not net you twice the horsepower. Horsepower is not a function of torque and engine speed, horsepower is the total amount of work an engine is capable of." Well, the first part of that is correct at least. However I think you are the one that needs to brush up on your reading, as horsepower is directly related to torque and engine speed. Dynos only measure one thing, torque, they give horsepower readings as a result of a very simple formula (see if you can follow this) torque times RPM divided by 5252 equals horsepower. Later in the same post you commented "My understanding is that torque is generated by the total amount of air/fuel you are burning, the length of the connecting rod and the length of the stroke of the crankshaft. How does engine rpm factor greatly in the amount of torque generated?" Can you not see the stupidity of that statement? What you've just basically said was..."If a motor with a certain bore and stroke makes XXX lb.-ft. of torque, then it is impossible for the same motor to make more torque while burning less fuel (with the same bore and stroke no less) later down the road with improvements in design." You can look at any number of motor designs through the years to see this is obviously not true. Generally, if a powerplant has say a 8 year run, the later motors will have made strides in both fuel economy and power output. Shooting your theory in the arse.
In closing, I could certainly come in here and portend to be an expert engine builder, but I'm not, and you claiming to be one doesn't make it so either.
In closing, I could certainly come in here and portend to be an expert engine builder, but I'm not, and you claiming to be one doesn't make it so either.
My 455 olds motor stock put out 500lbs@3200rpm and 370hp@4500(or some where around there) but the king of torque was the Buick 455 that put out 510lbs@2800rpm. My motor has been built by a personal friend(and Olds specialist) of Joe Mondello(Dr Olds) and is guesstimated to put out 425-450HP but the torque is near 560lbs. The more torque the better pulling from a low RPM you will have plus you will have better longevity from keeping your rpm's down.
Here is an old saying for ya.. "Horsepower gets the girl but torque wins the race."
Here is an old saying for ya.. "Horsepower gets the girl but torque wins the race."
Just to let you guys know, the very first post stated that the Integra GSR has 195HP. The GSR has 170, the type-r has 190 or 195 though. ALso I don't know why nobody has mentioned the S2000. It is a 2.0L engine that generates 240HP and 170ft-lbs torque. That is an engine. Who cares about 100hp/L with the type-r. Try 120hp/L. Damn that's efficient, although I wouldn't want it in my Blazer, have to floor it just to move the damn thing.
In fact here: HP vs. Torque
Maybe you can do a little research on your own the next time instead of blindly calling my post inaccurate.
Sorry, this will link directly to it.
Maybe you can do a little research on your own the next time instead of blindly calling my post inaccurate.
Sorry, this will link directly to it.
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