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Discussion Starter #1 (Edited)
Reference: April 2001 Road & Track.pg 69

Cars: BMW 330i, Lexus IS 300, Mercedes C320
All 5 speed AUTOMATICS, All RWD

Criteria.......BMW 330i.....Lexus IS 300...Mercedes C320
[email protected]@[email protected]
[email protected]@[email protected]
Weight.......3350 lbs...........3400lbs..................3480lbs
Redline........6400rpm........6400rpm..............6000rpm
Rear Tires...245/40-17.....215/45-17.........225/50-16
Final Drive...3.46:1............3.90:1...................3.46:1
1st gear..12.7/6400/37mph13.1/6400/35mph13.7/5800/34
0-20mph.......1.3................1.4.......................1.4
0-40mph.......3.5................3.9.....................3.5
2nd gear..6.9/64K/67mph 8.5/64K/54mph 8.4/6K/55mph
0-60mph.......6.5................7.1.....................6.8
3rd gear..4.9/64K/96mph 5.6/64K/83mph 5.2/6K/90mph
1/4 [email protected]@[email protected]

The BMW and Lexus are 3 liter dual overhead cam, 4-valve per cylinder, inline 6 cylinders. BMW has always used inline 6 engines as does the Chevy Trailblazer et all because they make more torque than V-6 engines the same displacement. That is unless the engine is a Mercedes single overhead cam with just 3 valves per cylinder and 3.2 liter displacement. As you can see from the hp and torque figures above, Mercedes opted for more torque than hp. It also has a lower redline than the DOHC engines at just 6K vs. 6.4K rpm.

The final drives for two of the car are identical and all three are close so there is not too much torque multiplication going on. (just as there isn't for the S2000) I included the multiplied final drive X gear ratio for each gear above, followed by the max rpm in gear and the corresponding mph figure for that gear.

I put the 0-20 and 0-40mph times next to the 1st gear figures to illustrate some of the nuances of the times. Likewise 2nd gear figures correspond to the 0-60 time and 3rd gear to the 1/4 mile time.

You will note first that the BMW is the lightest of the three and also has the most peak horsepower. Both the Lexus and Mercedes have identical peak horsepower but different torque which helps illustrate part of my point.

You will also note the BMW has MUCH wider rear tires (the drive wheels) than the other two cars. This SIGNIFICANTLY assists off the line traction vs. the other two cars. Its weight also assists it. Its higher horsepower to weight ratio assists it. BMWs well know propensity to have minimal drivetrain loss and high hp at the wheel assists it.

So why isn't it that much faster than the 130 lb heavier Mercedes that has 10 less horsepower?
 

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Discussion Starter #2
SoloIICole said:
Reference: April 2001 Road & Track.pg 69

Cars: BMW 330i, Lexus IS 300, Mercedes C320
All 5 speed AUTOMATICS, All RWD

Criteria.......BMW 330i.....Lexus IS 300...Mercedes C320
[email protected]@[email protected]
[email protected]@[email protected]
Weight.......3350 lbs...........3400lbs..................3480lbs
Redline........6400rpm........6400rpm..............6000rpm
Rear Tires...245/40-17.....215/45-17.........225/50-16
Final Drive...3.46:1............3.90:1...................3.46:1
1st gear..12.7/6400/37mph13.1/6400/35mph13.7/5800/34
0-20mph.......1.3................1.4.......................1.4
0-40mph.......3.5................3.9.....................3.5
2nd gear..6.9/64K/67mph 8.5/64K/54mph 8.4/6K/55mph
0-60mph.......6.5................7.1.....................6.8
3rd gear..4.9/64K/96mph 5.6/64K/83mph 5.2/6K/90mph
1/4 [email protected]@[email protected]

So why isn't the 330i that much faster than the 130 lb heavier Mercedes that has 10 less horsepower?
First compare the Mercedes and Lexus. Note that the C320 is 80 lbs heavier and has the same peak hp at about the same rpm. The tires are both fairly small for cars this size so traction is about the same. The 3.9 gear of the Lexus should aide its acceleration vs. the 3.46 of the Mercedes. The Lexus is lighter and revs much higher in first gear. Yet bu 40 mph the Mercedes is already pulling substantially. Note that the lighter, higher hp, higher revving BMW, with wide rear tires is also dead even at 40 mph.

Now as the cars go on to 60 mph, you note that only the BMW goes above 60 in 2nd gear. This is a major advantage! Yet it is only 3 tenths faster than the Mercedes...probably due to the gearing.

Now go onto third gear and the quarter mile. The Bimmer is revving high. It has 10 more horses than either competing car. It should be smoking these guys.......and it is smoking the Lexus, but not the C320. Why?

See that peak torque from....yes you are reading that right....3000 rpm to 4600 rpm. It is making peak torque of 229 lb-ft during that entire range. As the testers point out it feels like it is going faster than it is because it has such great low an mid range torque. And cars accelerate at the fastest rate at their peak torque.

And look, once again gearing screws up the C320 as it must shift prior to the 1/4 mile while the BMW does not. Nevertheless, it crosses the 1/4 mile just one tenth slower and less than 1 mph faster. Could it be that Mercedes is gearing for real world driving while BMW is gearing for road test figures? They are different demographics of drivers, with Bimmer drivers having sportier aspirations, and Mercedes knowing that its drivers will like the powerful feel without being concerned about the actual times.

So you can talk bicycles and gearing and redlines and torque multiplication until you are blue in the face. The reality is that torque WORKS. (pun intended). No I did not look up the actual torque curves. But a low peak torque car like the S2000 don't ever have a torque curve HIGHER than the peak torque and a 4.1 final drive will never multiply that miniscule torque by very much.

So argue that you want high torque high in the rev range, or mid or low....but don't argue that torque is irrelevant or that engine torque is unrelated to wheel torque.
 

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Re: Re: A tale of 3 cars: a study in torque vs. hp

SoloIICole said:


First compare the Mercedes and Lexus. Note that the C320 is 80 lbs heavier and has the same peak hp at about the same rpm. The tires are both fairly small for cars this size so traction is about the same. The 3.9 gear of the Lexus should aide its acceleration vs. the 3.46 of the Mercedes. The Lexus is lighter and revs much higher in first gear. Yet bu 40 mph the Mercedes is already pulling substantially. Note that the lighter, higher hp, higher revving BMW, with wide rear tires is also dead even at 40 mph.

Now as the cars go on to 60 mph, you note that only the BMW goes above 60 in 2nd gear. This is a major advantage! Yet it is only 3 tenths faster than the Mercedes...probably due to the gearing.

Now go onto third gear and the quarter mile. The Bimmer is revving high. It has 10 more horses than either competing car. It should be smoking these guys.......and it is smoking the Lexus, but not the C320. Why?

See that peak torque from....yes you are reading that right....3000 rpm to 4600 rpm. It is making peak torque of 229 lb-ft during that entire range. As the testers point out it feels like it is going faster than it is because it has such great low an mid range torque. And cars accelerate at the fastest rate at their peak torque.

And look, once again gearing screws up the C320 as it must shift prior to the 1/4 mile while the BMW does not. Nevertheless, it crosses the 1/4 mile just one tenth slower and less than 1 mph faster. Could it be that Mercedes is gearing for real world driving while BMW is gearing for road test figures? They are different demographics of drivers, with Bimmer drivers having sportier aspirations, and Mercedes knowing that its drivers will like the powerful feel without being concerned about the actual times.

So you can talk bicycles and gearing and redlines and torque multiplication until you are blue in the face. The reality is that torque WORKS. (pun intended). No I did not look up the actual torque curves. But a low peak torque car like the S2000 don't ever have a torque curve HIGHER than the peak torque and a 4.1 final drive will never multiply that miniscule torque by very much.

So argue that you want high torque high in the rev range, or mid or low....but don't argue that torque is irrelevant or that engine torque is unrelated to wheel torque.
you know... i stayed pretty much out of this one from the get-go, but i think (and some may agree) that this horse is pretty much GLUE by now. torque is important and hp is important. as one famous mag said, when comparing a jeep wrangler to a mazda miata, "torque gets you off the line, horsepower gets you down the road." you guys, in my opinion, are equally right in your own perspective views. you each put some good equations and facts out for all to see. but would you both agree that if the driver sucks, the VEHICLE will suck as well? regardless of tq and hp numbers??? i mean, c'mon guys, read the thread, this was about a car (s2000 for those that have no idea what im talking about) and an m3 (at first) and then an altima. the altima won. the driver of the altima, if i recall correctly, said that maybe the s2000 driver sucked. THATS what this is about. leave it alone already. BURY THE HORSE! get some sleep.
 

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SoloIICole said:

Criteria.......BMW 330i.....Lexus IS 300...Mercedes C320
[email protected]@[email protected]
[email protected]@[email protected]
Weight.......3350 lbs...........3400lbs..................3480lbs
Redline........6400rpm........6400rpm..............6000rpm
Rear Tires...245/40-17.....215/45-17.........225/50-16
Final Drive...3.46:1............3.90:1...................3.46:1
1st gear..12.7/6400/37mph13.1/6400/35mph13.7/5800/34
0-20mph.......1.3................1.4.......................1.4
0-40mph.......3.5................3.9.....................3.5
2nd gear..6.9/64K/67mph 8.5/64K/54mph 8.4/6K/55mph
0-60mph.......6.5................7.1.....................6.8
3rd gear..4.9/64K/96mph 5.6/64K/83mph 5.2/6K/90mph
1/4 [email protected]@[email protected]

YAWN!

Three cars that are within 10HP of eachother, within 15lb-ft of eachother, redline within 400rpms of eachother, within a .44 of final drive gear ratio and within .3 seconds of eachother in the 1/4 mile.

What are you trying to prove?

The cars are SO CLOSE to eachother in ALL aspects of performance that is completely pointless to draw any conclusions about anything. The drivers bowel movements are probably more affecting the end results than those 10HP or 15lb-ft differences.

Why don't you try to compare a 150lb-ft Golf TDI vs. a 150lb-ft Honda S2000, both at 2700lbs, and Golf running high 16's while Honda running high 13's, and tell me that torque ALONE is relevant?
 

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Three cars that are within 10HP of eachother, within 15lb-ft of eachother, redline within 400rpms of eachother, within a .44 of final drive gear ratio and within .3 seconds of eachother in the 1/4 mile.
Don't forget automatic transmissions that probably do not have the exact same efficiency, or shift gears in the the exact same amount of time.

Why don't you try to compare a 150lb-ft Golf TDI vs. a 150lb-ft Honda S2000, both at 2700lbs, and Golf running high 16's while Honda running high 13's, and tell me that torque ALONE is relevant?
I'm merely speculating here, but I would expect the Golf to win the race to 20 mph. If that's what's important to you, the Golf is likely a great car for that. For me, I spend my time traveling down 1/2-1 mile back straights. I'll take the S2000 for that application :)

A possibly better comparison would be a 175 ft-lb Sentra SE-R Spec-V vs a 135 ft-lb (?less?) Integra Type R. Both are fwd, both have excellent limited slips, both weigh within ~100 lbs of one another. One runs the 1/4 in 14.5 seconds, the other does it in 15.4. Guess which one is which?

The best single sentence I can come up with to sum it all up appeared in an article I read several years ago :Torque is your friend, but horsepower is still King.

What most people are missing here is torque at high rpms makes lots of horsepower. Plug it into the equation. How much hp does 100 ft-lbs at 3000rpms make? How much hp does 100 ft-lbs at 6000 rpms make?

BTW, I really can't see us getting a whole lot more out of this discussion.
 

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Discussion Starter #6 (Edited)
Re: Re: A tale of 3 cars: a study in torque vs. hp

YellowBullet said:


YAWN!

Three cars that are within 10HP of eachother, within 15lb-ft of eachother, redline within 400rpms of eachother, within a .44 of final drive gear ratio and within .3 seconds of eachother in the 1/4 mile.

What are you trying to prove?

The cars are SO CLOSE to eachother in ALL aspects of performance that is completely pointless to draw any conclusions about anything. The drivers bowel movements are probably more affecting the end results than those 10HP or 15lb-ft differences.

Why don't you try to compare a 150lb-ft Golf TDI vs. a 150lb-ft Honda S2000, both at 2700lbs, and Golf running high 16's while Honda running high 13's, and tell me that torque ALONE is relevant?
Unlike your ludicrous Golf TDI vs. S2000 comparison, I purposely chose cars similar in character, weight, horsepower and torque. The Lexus and Mercedes had identical hp, weight, tire traction...the only major difference (its called a variable, duh) was torque....and that's why the Mercedes was faster. The 330i and Mercedes showed that even giving the 330i every advantage: 130lbs less weight, bigger tires for greater traction, 10 more bhp and probably considerably more than that at the wheel.....the 330i could not walk on the torquier C320 in the 1/4 mile. I've said all along that both Hp and weight are important. BMW and Lexus seem to think so as well with their in-line 6 designs that produce pretty substantial torque and horsepower.

I agree completely with MaddMatt's statement that high torque at high rpm makes high horsepower per the formula Hp=TorqueXRPM/5252. But as I pointed out earlier, you cannot get both high torque and very high rpm in the same street car because the high torque requires either large displacement or super/turbocharging and neither can withstand higher RPMs for very long. Nine grand in a streetable S2000 is race car territory in NASCAR with big V-8s that can blow at 400 miles or less...ask Jeff Burton at Michigan last Sunday. So if you cannot have high RPM and high Torque, your next best bet for a street car is to have high torque at as high an RPM that is feasible.

Look at the following examples:
5000rpmX300lb-ft=1500000
10000rpmX150lb-ft=1500000
5000romX600lb-ft=3000000
10000rpmX300lb-ft= 3000000

For simplicity, I left out the division by 5252, but if you must know the 15-based number is 285hp, the 30-based is 570hp.
Which engine would be easiest to build for the street. Obviously, the 5000rpm X 300lb-ft motor. The Mustang GT is close to that figure. The other motor is an S2000 on steroids. It ain't happening in the year 2002 or foreseeable future.

Which motor is easier to build to create the modified higher horsepower number. Once again, there are numerous examples in the supercar showdown of 5000rpm engines making 600lb-ft of peak torque. Show me one streetable motor that can do the 10,000 rpm and make 300 lb-ft and last very long.
 

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Discussion Starter #7 (Edited)
MaddMatt said:


A possibly better comparison would be a 175 ft-lb Sentra SE-R Spec-V vs a 135 ft-lb (?less?) Integra Type R. Both are fwd, both have excellent limited slips, both weigh within ~100 lbs of one another. One runs the 1/4 in 14.5 seconds, the other does it in 15.4. Guess which one is which?

The best single sentence I can come up with to sum it all up appeared in an article I read several years ago :Torque is your friend, but horsepower is still King.

What most people are missing here is torque at high rpms makes lots of horsepower. Plug it into the equation. How much hp does 100 ft-lbs at 3000rpms make? How much hp does 100 ft-lbs at 6000 rpms make?
MaddMatt, you probably recall that both Sport Compact Car and Grassroots Motorsports magazines chastized Nissan for claiming that the 2002 SE-R Spec V made 175 bhp when dyno tests showed the true figure at the wheel to be in the 138-141hp range, which is far less than typical for drivetrain loss. In other words, if mass-produced in greater numbers, Nissan would have had its own little 155 hp Miata/99 Cobra scandal. The SE-R makes nowhere near the hp the Integra Type R makes, it is heavier, has 17" large tires for increased rotational inertia and the Type R that does 14.5 sec. in the 1/4 mile is atypical at best.....more like 14.8 sec. Altima territory. Maybe a comparison with the SVT Focus would be more appropriate......similar hp and weight but the Focus has less torque......and is slower..... [email protected] vs. [email protected] for the Spec V. In 0-100mph tests the times are 20.2 vs. 19.3. (Road&Track Road Test Summary) That is an apples to apples comparison.
 

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Discussion Starter #8
Well here's an example where I gotta simultaneously eat crow and gloat.

http://www.mcclatchie.com/reviews/S2000R.html

In 2003, if you have $54K (in your dreams with dealer mark-up), you can fix every S2000 ill and have the baddest car around. They recognized that they needed more torque so they slapped on two more cylinders raising the displacement to 3 liters, creating an in-line 6 (sound familiar) to increase the force end of the torque equation. They raised the compression ratio to 11.7:1 to increase the force end of the torque formula. Net result is the S2000R will have 57% more peak torque, and at 3K rpm, torque is up 65%. Peak torque is 230 lb-ft @6000rpm.

Now peak horsepower also increases by 50% (surprise, 50% more cylinders) to [email protected] rpm.

Redline stays at 9 grand. Must be something to that high-rpm-hurts-reliability thing.

Finally, they realized they had a porker on their hands so they put her on a diet, losing nearly 400 lbs for a curb weight of 2412 lbs.

Now THAT....is a supercar. I bow to the setting sun.......
 

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You are a god-damn moron! that is obviously fake! does honda even have an inline 6? And while doing so, they shaved over 300lbs off the already extreemly light weight car?!

:rolleyes: Do you beleive everything you read!? stick to magazine racing, and horsepower caculators, etc :rolleyes:
 

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The SE-R makes nowhere near the hp the Integra Type R makes,
That is my point exactly. The Type R has less torque, but accelerates much faster than the Spec-V. Horsepower is King! So the V doesn't make the advertized 175 ft lbs. It's still got way more (30 ft lbs?) peak torque than the R, and is much slower.

in the 1/4 mile is atypical at best
Atypical is 14.3, which I've seen published and witnessed at the strip. I couldn't believe it either. The thing is, many parts of the R are hand polished. Some better than others. Leading to engines with the greatest variation in power I've ever seen.

That is an apples to apples comparison.
Not really when you consider the very nice limited slip the V has over the SVT.

Let's try this one more time, I think I have a winning comparo. Spec V (170ish ft lbs @ ~3500 rpm) vs. the new Mazdaspeed Protege (155 ft lbs at 4500 rpms). Car & Driver has the Protege ~.5 second quicker to 60, and ~.3 quicker through the 1/4. Both are fwd, both are ~2800 lbs, both make ~170ish hp (Mazda=170, V=175 or so Nissan says), both have limited slips.

I'm going to keep at this until I convince you that less torque at higher rpms usually can beat more torque at lower rpms.
 

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Discussion Starter #12
Br0kWRX said:
You are a god-damn moron! that is obviously fake! does honda even have an inline 6? And while doing so, they shaved over 300lbs off the already extreemly light weight car?!

:rolleyes: Do you beleive everything you read!? stick to magazine racing, and horsepower caculators, etc :rolleyes:
Easy there smart aleck moose jockey. I guess I got suckered by an extremely well-written, highly plausible scenario. You think an S2000 is an already extremely lightweight car? Check out the similarly-sized MR Spyder.

I guess my crow-eating was premature.....there is no 300 lb-ft/10,000 rpm car in the works. Guess we'll have to stick with no replacement for displacement.

Before branding me as a magazine road warrior, best check-out my autocross experience in my signature. Not impressed, then know that I drove 3 years on the autobahn before you were born.
Still, not impressed. I flew helicopters in the Army for 11 years....but I drive much better than I fly. There are plenty better than me out there....several in these forums.......but I know I have nothing to worry about from one whose claim to fame is their 1/4 time. Go sip a cold one and ponder all the great road cars designed and constructed by Canadian companies....oh shit, wouldn't get much drinking done that way!
 

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Discussion Starter #13
Frmr97GXE said:
Easy there smart-ass cat humper. Still waiting for some sign of intelligent original thought from you, pussy cat (less the cat).
 

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Discussion Starter #14
MaddMatt said:


That is my point exactly. The Type R has less torque, but accelerates much faster than the Spec-V. Horsepower is King! So the V doesn't make the advertized 175 ft lbs. It's still got way more (30 ft lbs?) peak torque than the R, and is much slower.


Atypical is 14.3, which I've seen published and witnessed at the strip. I couldn't believe it either. The thing is, many parts of the R are hand polished. Some better than others. Leading to engines with the greatest variation in power I've ever seen.


Not really when you consider the very nice limited slip the V has over the SVT.

Let's try this one more time, I think I have a winning comparo. Spec V (170ish ft lbs @ ~3500 rpm) vs. the new Mazdaspeed Protege (155 ft lbs at 4500 rpms). Car & Driver has the Protege ~.5 second quicker to 60, and ~.3 quicker through the 1/4. Both are fwd, both are ~2800 lbs, both make ~170ish hp (Mazda=170, V=175 or so Nissan says), both have limited slips.

I'm going to keep at this until I convince you that less torque at higher rpms usually can beat more torque at lower rpms.
I'll have to think this one over, Madd Matt. I left the Grassroots Motorsport magazine article at the store but it showed that the SVT Focus had MORE hp at the wheel than the Spec V. It also showed a 48 mph max speed in 2nd gear vs. 62 for the Focus, yet the Spec V was faster with one less shift. That Spec V is just a flaky example....not too many inline 2.5 liter four-bangers out there. I suspect the better comparo is the SVT Focus vs. the MazdaSpeed Protege. Both have 170 hp....the constant.....both weigh the same...another constant, both have 17" wheels, another constant (same rotational inertia) the variable is torque......and we know which one is faster. At this little hp I don't think you can say the LSD would help straight-line acceleration much...its more for out of corners.

I can be convinced, but for every example you guys come up with I find just as many favoring torque....and horsepower.
 

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I can be convinced, but for every example you guys come up with I find just as many favoring torque....and horsepower.
You see, the thing is, I think it's all in the horsepower. Well, hp to weight ratio.

As far as the V goes, I personally think that Nissan screwed up the transmission ratios. The torque peak is ~3500 rpms. By 5 grand, the party is over and torque is nose diving. Their gear selections, if you shift at redline, keeps you above the torque peak. And I think you and I both agree that the best acceleration occurs at the torque peak.

I want to see a dyno sheet on the SVT. I drove one at a press event in June, and it just seemed a little weak to me.
 

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MaddMatt said:


That is my point exactly. The Type R has less torque, but accelerates much faster than the Spec-V. Horsepower is King! So the V doesn't make the advertized 175 ft lbs. It's still got way more (30 ft lbs?) peak torque than the R, and is much slower.


Atypical is 14.3, which I've seen published and witnessed at the strip. I couldn't believe it either. The thing is, many parts of the R are hand polished. Some better than others. Leading to engines with the greatest variation in power I've ever seen.

The arguement was not weather or not a car with less horsepower and more torque can beat a car with more horsepower andl less torque. It was between two cars with equal horsepower but one had twice the torque of the other.

FYI, according to the NHRA the track I race at is the fastest in the country. I've never seen a Type R run a 14.5 bone stock.
 

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Discussion Starter #17 (Edited)
Redline said:


The arguement was not weather or not a car with less horsepower and more torque can beat a car with more horsepower andl less torque. It was between two cars with equal horsepower but one had twice the torque of the other.

FYI, according to the NHRA the track I race at is the fastest in the country. I've never seen a Type R run a 14.5 bone stock.
Hee, hee, hee. I've been backing off addressing this hypothetical engine situation because I pictured some giant diesel engine and was hung up on that. But Redline is right! Look below.

Eng.1:200 hp max/1000lb-ft max..Eng.2: 200hp/200lb-ft
200 hp=1000lb-ft. X 1050rpm....38 hp=200lb-ft X 1000rpm
200 hp= 500lb-ft X 2100rpm
200 hp= 333lb-ft X 3150 rpm....119 hp=200lb-ft X 3,126rpm
200 hp= 250lb-ft X 4200rpm
200 hp= 167 lb-ft X 6300 rpm..200 hp=200lb-ft X 5252rpm

Sorry guys. Even at 6300 rpm, hypothetical engine 1 could make 167 lb-ft and still not exceed the 200 hp level. The other engine on the other hand cannot exceed 200 hp so above 5252 rpm the torque must decrease as rpm increases to 6 grand. Of course I imagine engine 1 would be rather LARGE and diesel...but it works!

;) Ain't math fun!

I also must agree with Redline on the Integra Type R. I found an old road test summary that showed a 14.8 time. If the guy ran 14.3 it was either 20 degrees outside at sea level or he lied about his lack of mods. I don't think I screwed up the math above. I've got no calculator and left my reading glasses at work.

Grassroots dynoed the 170hp SVT Focus at 147.3 hp at the wheel. The 175hp Spec V dynoed at 138.2 hp at the wheel so the MazdaSpeed Protege vs. SVT Focus comparison is more fair. Both 170 hp, one clear winner C&D times: 6.9/15.4 vs. 7.8/16.1 with the same weight, same ponies, same wheel diameter/tire size, similar gearing (62mph vs 68 mph 2nd gear) and greater torque in the Protege.

MaddMatt, you mention press days. Are you a car journalist?

Good night, must sleep.
 

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SoloIICole said:


Hee, hee, hee. I've been backing off addressing this hypothetical engine situation because I pictured some giant diesel engine and was hung up on that. But Redline is right! Look below.

Eng.1:200 hp max/1000lb-ft max..Eng.2: 200hp/200lb-ft
200 hp=1000lb-ft. X 1050rpm....38 hp=200lb-ft X 1000rpm
200 hp= 500lb-ft X 2100rpm
200 hp= 333lb-ft X 3150 rpm....19 hp=200lb-ft X 3,126rpm
200 hp= 250lb-ft X 4200rpm
200 hp= 167 lb-ft X 6300 rpm..200 hp=200lb-ft X 5252rpm

Sorry guys. Even at 6300 rpm, hypothetical engine 1 could make 167 lb-ft and still not exceed the 200 hp level. The other engine on the other hand cannot exceed 200 hp so above 5252 rpm the torque must decrease as rpm increases to 6 grand. Of course I imagine engine 1 would be rather LARGE and diesel...but it works!

;) Ain't math fun!

You STILL don't get it, do you?

The point is NOT whether a 200HP/1000lb-ft car can beat a 200HP/200lb-ft car. OF COURSE IT CAN, and nobody is disputing that.

The point is that a 200HP/1000lb-ft car WILL NOT NECESSARILY BEAT A 200hp/200lb-ft car. They can tie, or either one can win depending on their torque curves and gearing.

In the example that you are submitting above, the 200hp/1000lb-ft car HAS A BETTER TORQUE CURVE, that's why it would win, NOT because of the 1000lb-ft figure.


I can be convinced, but for every example you guys come up with I find just as many favoring torque....and horsepower.


Let me illustrate how wrong you are:

I claim that ALL blond people are stupid.

You, of course, jump out on me and mention a couple of examples of smart blond people.

I retort: "Ah HA! But for every example you can come up with smart blond people I can find just as many that are stupid"

Therefore ALL blond people are stupid.




To prove that something is true, you have to prove it to be true ALWAYS, not just to come up with a couple of examples.

On the other hand, to prove that peak torque # DOES NOT MATTER, all I need to do is to come up with ONE counter example. Which I did.
 

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Redline said:


The arguement was not weather or not a car with less horsepower and more torque can beat a car with more horsepower andl less torque. It was between two cars with equal horsepower but one had twice the torque of the other.

And I showed you an example where a 200HP/500lb-ft car is CLEARLY MUCH FASTER than a 200HP/1000lb-ft car.
 

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MaddMatt:

Although I agree with you on most of the HP/torque issues, and you seem to understand these issues a lot better than Redline or SoloIICole, there's ONE thing that I disagree with you:

You seem to believe that making peak torque at high rpm is better than making it at low rpms.

That's not really true.

You don't have to make your peak torque at high rpms, you just need to keep making a substantial amount of your torque at high rpms so that you can use shorter gearing.

For example, let's look a car that makes a peak of 200lb-ft at 6000rpms, and the torque falls off quickly after that.

A different car can make peak torque of 200lb-ft at only 2000rpms, but if the torque REALLY SLOWLY falls of to, say 195lb-ft at 6000rpms, and continues to fall to, say 180lb-ft at 8000rpms, the second car could use much shorter gears and would be a lot faster than the first car.


Actually, if you take a look at two cars with identical peak numbers, say 200HP/200lb-ft, the one that is making its peak torque at lower rpms will in general have a better torque curve and it should be slightly faster than the one making peak torque at higher rpms.

Car 1: starts at 200lb-ft at 1000rpms and falls linearly to 100lb-ft at 10504rpms, for 200hp at 10504rpms.

Car 2: starts at 0lb-ft at 1000rpms and rises linearly to 200lb-ft at 5252rpms, for 200HP at 5252rpms.

Car 1 could use two times shorter gears and it would be A LOT faster than Car 2.
 
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