Altima SE V-6 vs. Accord LX V-6

"Sean Dinh" > wrote in message
...
> You are so wrong. Horsepower is everything. Since the Altima has a 3.5 L
vs the
> Accord's 3.0 L, the Altima has more low end power. It would take off at
the line
> faster.

Actually torque is much more important at the lower rpm than you seem to
understand. In fact, that low end power you are thinking of is actually
more torque than anything else. Torque *is* a specific measurement of the
vehicle's ability to push/pull an object/weight from a stop or lower speed.
You will reach the peak torque of an engine in the lower rpm range, exactly
where most of your acceleration occurs, while your peak horsepower occurs in
the upper rpm range, where you will accelerate slower. Don't beleive me?
Look at Horsepower and Torque charts and you will see where the peaks occur.

>Every gear changes reduce the engine's rpm. This benefit bigger engines
> because they have more hp at lower rpm.

Why does this occur? You want to drop your rpms to a point where you can
take the most advantage of torque and horsepower, usually around 5200rpm, to
accelerate. Not saying that horsepower does nothing, in fact it does help
sustain and increase speed at the upper rpm when the vehicle is already
moving. Think of horsepower as related to the top speed of the vehicle.
BTW, just because an engine is bigger, doesn't mean it has more power.

> At 1000 rpm, a 4 L engine would make 2x as much torque as a 2 L engine.
But, for
> some reason beyond my comprehension, people don't realize that it make as
much
> as 2x the power too. Torque only twist, but power moves things.

Actually, just because and engine is twice the size of another doesn't mean
that it is twice as powerful. Much of an engines abilitly is based on it's
design. If your idea held true, all 2 liter engines would put out the same
power. BTW, what do you think torque is twisting? I would say it's the
axles which is connected to the wheels which moves a car forward. How does
horsepower move the car?

> I could make more torque on my bicycle than the Altima's engine, but there
is no
> way my 1/3 hp could move the Altima as fast.

I highly doubt you could produce more torque than the VQ35DE on your
bicycle.

If you want to get a little more technical:
http://www.datsuns.com/Tech/tech_dept.htm

> Hawaii_SE-R wrote:
>
> > Horsepower is not everything. The Honda falls behind primarily due to
less
> > torque. Accord has 240hp/212tq while the Altima has 250hp/249tq.
Torque
> > affects acceleration directly by the sheer ability to move mass. With
15%
> > less torque, it should be obvious why the Altima will out accelerate the
> > Accord. Gearing would also play a part.
>

Hawaii_SE-R wrote:

> "Sean Dinh" > wrote in message
> ...
> > You are so wrong. Horsepower is everything. Since the Altima has a 3.5 L
> vs the
> > Accord's 3.0 L, the Altima has more low end power. It would take off at
> the line
> > faster.
>
> Actually torque is much more important at the lower rpm than you seem to
> understand. In fact, that low end power you are thinking of is actually
> more torque than anything else. Torque *is* a specific measurement of the
> vehicle's ability to push/pull an object/weight from a stop or lower speed.
> You will reach the peak torque of an engine in the lower rpm range, exactly
> where most of your acceleration occurs, while your peak horsepower occurs in
> the upper rpm range, where you will accelerate slower. Don't beleive me?
> Look at Horsepower and Torque charts and you will see where the peaks occur.

Sean is correct and you are incorrect. Looking at a chart to find the torque
and hp peaks doesn't tell you where maximum acceleration occurs.
Easy to show from Newton's second law (F=ma) that maximum acceleration occurs at
the POWER peak in any gear. Sorry, but you just have to do the physics here.

>
>
> >Every gear changes reduce the engine's rpm. This benefit bigger engines
> > because they have more hp at lower rpm.
>
> Why does this occur? You want to drop your rpms to a point where you can
> take the most advantage of torque and horsepower, usually around 5200rpm, to
> accelerate. Not saying that horsepower does nothing, in fact it does help
> sustain and increase speed at the upper rpm when the vehicle is already
> moving. Think of horsepower as related to the top speed of the vehicle.
> BTW, just because an engine is bigger, doesn't mean it has more power.
>
> > At 1000 rpm, a 4 L engine would make 2x as much torque as a 2 L engine.
> But, for
> > some reason beyond my comprehension, people don't realize that it make as
> much
> > as 2x the power too. Torque only twist, but power moves things.
>
> Actually, just because and engine is twice the size of another doesn't mean
> that it is twice as powerful. Much of an engines abilitly is based on it's
> design. If your idea held true, all 2 liter engines would put out the same
> power. BTW, what do you think torque is twisting? I would say it's the
> axles which is connected to the wheels which moves a car forward. How does
> horsepower move the car?

Again, Sean is basically correct. The physics of combustion is a constant for
all engines so maximum PRESSURE within the cylinders without detonation is
basically a constant (all 2 liter engines don't put out the same power because
not everyone achieves the same volumetric efficiency, designs for premium fuel
etc) Torque is pressure x displacement - so yes, an engine twice the size puts
out twice the torque AND hp (hence acceleration) at a given rpm - provided
intake and exhaust systems give the same volumetric efficiency at that rpm.
These are all basic concepts for Engine Design 101.

>
>
> > I could make more torque on my bicycle than the Altima's engine, but there
> is no
> > way my 1/3 hp could move the Altima as fast.
>
> I highly doubt you could produce more torque than the VQ35DE on your
> bicycle.
>
> If you want to get a little more technical:
> http://www.datsuns.com/Tech/tech_dept.htm
>
> > Hawaii_SE-R wrote:
> >
> > > Horsepower is not everything. The Honda falls behind primarily due to
> less
> > > torque. Accord has 240hp/212tq while the Altima has 250hp/249tq.
> Torque
> > > affects acceleration directly by the sheer ability to move mass. With
> 15%
> > > less torque, it should be obvious why the Altima will out accelerate the
> > > Accord. Gearing would also play a part.
> >

Frank

1. Torque, by definition, is just a term to describe the strength of the
twisting motion. It has nothing to do with acceleration. Just because there are
a lot of idiots, including magazine editors, miss understand the term, that does
not make it right. You should replace your "torque" with "horsepower".

2. At low rpm, like 1k-3k rpm, most engine put out the same horsepower/volume.
Hence, double the engine, you double the power. What differentiate a good engine
from an average engine is how much power it could produce at high rpm, like
above 5200. This region of rpm is where VTEC and Vanos and such enhance engine
power.

3. 100 lb person on a 3' crank on a bicycle produce 300 ft*lb of torque. A 300
lb person standing on a 1' crank produce 300 ft*lb of torque. I, standing on a
4' breaker bar on the wheel axle produce more torque than a 3.5 L Altima.
However, the car doesn't move much because I make little horsepower. There is no
doubt that I could produce 1000 ft*lb. All I need is to extend the crank to 10'.

Hawaii_SE-R wrote:

> Actually torque is much more important at the lower rpm than you seem to
> understand. In fact, that low end power you are thinking of is actually
> more torque than anything else. Torque *is* a specific measurement of the
> vehicle's ability to push/pull an object/weight from a stop or lower speed.
> You will reach the peak torque of an engine in the lower rpm range, exactly
> where most of your acceleration occurs, while your peak horsepower occurs in
> the upper rpm range, where you will accelerate slower. Don't beleive me?
> Look at Horsepower and Torque charts and you will see where the peaks occur.
>
> >Every gear changes reduce the engine's rpm. This benefit bigger engines
> > because they have more hp at lower rpm.
>
> Why does this occur? You want to drop your rpms to a point where you can
> take the most advantage of torque and horsepower, usually around 5200rpm, to
> accelerate. Not saying that horsepower does nothing, in fact it does help
> sustain and increase speed at the upper rpm when the vehicle is already
> moving. Think of horsepower as related to the top speed of the vehicle.
> BTW, just because an engine is bigger, doesn't mean it has more power.
>
> > At 1000 rpm, a 4 L engine would make 2x as much torque as a 2 L engine.
> But, for
> > some reason beyond my comprehension, people don't realize that it make as
> much
> > as 2x the power too. Torque only twist, but power moves things.
>
> Actually, just because and engine is twice the size of another doesn't mean
> that it is twice as powerful. Much of an engines abilitly is based on it's
> design. If your idea held true, all 2 liter engines would put out the same
> power. BTW, what do you think torque is twisting? I would say it's the
> axles which is connected to the wheels which moves a car forward. How does
> horsepower move the car?
>
> > I could make more torque on my bicycle than the Altima's engine, but there
> is no
> > way my 1/3 hp could move the Altima as fast.
>
> I highly doubt you could produce more torque than the VQ35DE on your
> bicycle.
>
> If you want to get a little more technical:
> http://www.datsuns.com/Tech/tech_dept.htm

Horespower does not get you off the line or out of the corners. It is
torque.

Sean Dinh wrote:

> 1. Torque, by definition, is just a term to describe the strength of the
> twisting motion. It has nothing to do with acceleration. Just because there are
> a lot of idiots, including magazine editors, miss understand the term, that does
> not make it right. You should replace your "torque" with "horsepower".
>
> 2. At low rpm, like 1k-3k rpm, most engine put out the same horsepower/volume.
> Hence, double the engine, you double the power. What differentiate a good engine
> from an average engine is how much power it could produce at high rpm, like
> above 5200. This region of rpm is where VTEC and Vanos and such enhance engine
> power.
>
> 3. 100 lb person on a 3' crank on a bicycle produce 300 ft*lb of torque. A 300
> lb person standing on a 1' crank produce 300 ft*lb of torque. I, standing on a
> 4' breaker bar on the wheel axle produce more torque than a 3.5 L Altima.
> However, the car doesn't move much because I make little horsepower. There is no
> doubt that I could produce 1000 ft*lb. All I need is to extend the crank to 10'.
>
> Hawaii_SE-R wrote:
>
>
>>Actually torque is much more important at the lower rpm than you seem to
>>understand. In fact, that low end power you are thinking of is actually
>>more torque than anything else. Torque *is* a specific measurement of the
>>vehicle's ability to push/pull an object/weight from a stop or lower speed.
>>You will reach the peak torque of an engine in the lower rpm range, exactly
>>where most of your acceleration occurs, while your peak horsepower occurs in
>>the upper rpm range, where you will accelerate slower. Don't beleive me?
>>Look at Horsepower and Torque charts and you will see where the peaks occur.
>>
>>
>>>Every gear changes reduce the engine's rpm. This benefit bigger engines
>>>because they have more hp at lower rpm.
>>>
>>Why does this occur? You want to drop your rpms to a point where you can
>>take the most advantage of torque and horsepower, usually around 5200rpm, to
>>accelerate. Not saying that horsepower does nothing, in fact it does help
>>sustain and increase speed at the upper rpm when the vehicle is already
>>moving. Think of horsepower as related to the top speed of the vehicle.
>>BTW, just because an engine is bigger, doesn't mean it has more power.
>>
>>
>>>At 1000 rpm, a 4 L engine would make 2x as much torque as a 2 L engine.
>>>
>>But, for
>>
>>>some reason beyond my comprehension, people don't realize that it make as
>>>
>>much
>>
>>>as 2x the power too. Torque only twist, but power moves things.
>>>
>>Actually, just because and engine is twice the size of another doesn't mean
>>that it is twice as powerful. Much of an engines abilitly is based on it's
>>design. If your idea held true, all 2 liter engines would put out the same
>>power. BTW, what do you think torque is twisting? I would say it's the
>>axles which is connected to the wheels which moves a car forward. How does
>>horsepower move the car?
>>
>>
>>>I could make more torque on my bicycle than the Altima's engine, but there
>>>
>>is no
>>
>>>way my 1/3 hp could move the Altima as fast.
>>>
>>I highly doubt you could produce more torque than the VQ35DE on your
>>bicycle.
>>
>>If you want to get a little more technical:
>>http://www.datsuns.com/Tech/tech_dept.htm
>>
>

Harry Cox wrote:

> On Wed, 08 Dec 2004 23:02:01 GMT, Raybender >
> wrote:
>
> >
> >
> >Hawaii_SE-R wrote:
> >
> >> "Sean Dinh" > wrote in message
> >> ...
> >> > You are so wrong. Horsepower is everything. Since the Altima has a 3.5 L
> >> vs the
> >> > Accord's 3.0 L, the Altima has more low end power. It would take off at
> >> the line
> >> > faster.
> >>
> >> Actually torque is much more important at the lower rpm than you seem to
> >> understand. In fact, that low end power you are thinking of is actually
> >> more torque than anything else. Torque *is* a specific measurement of the
> >> vehicle's ability to push/pull an object/weight from a stop or lower speed.
> >> You will reach the peak torque of an engine in the lower rpm range, exactly
> >> where most of your acceleration occurs, while your peak horsepower occurs in
> >> the upper rpm range, where you will accelerate slower. Don't beleive me?
> >> Look at Horsepower and Torque charts and you will see where the peaks occur.
> >
> >Sean is correct and you are incorrect. Looking at a chart to find the torque
> >and hp peaks doesn't tell you where maximum acceleration occurs.
> >Easy to show from Newton's second law (F=ma) that maximum acceleration occurs at
> >the POWER peak in any gear. Sorry, but you just have to do the physics here.
>
> I've wondered about torque and HP too and didn't know the answer but
> would like to.
>
> As you state, F = ma (force equals mass times acceleration)
>
> So, a = F/m (acceleration equals force divided by mass).
>
> To accelerate the car, we need F (force).
>
> Torque is force times distance. T = Fd
>
> Solving for F and plugging that into our acceleration equation, we get
>
> a = T/d/m (acceleration equals torque divided by distance divided by
> mass).
>
> For your particular car, the distance and the mass don't change. Hence
> acceleration depends on torque only.
>
> As the car goes faster and faster, you need horsepower to maintain
> that torque at the higher RPMs.
>
> There's some interesting background at
> http://science.howstuffworks.com/fpte.htm.

Here's the way you need to work it out. Then to prove it, go test the acceleration
of your car in second gear somewhere past the torque peak and up on the hp curve, and
compare to acceleration AT THE SAME SPEED in third gear down near the peak of the
torque curve.

Start from

F= ma Newtons second law

Now the car is moving as you accelerate so.....

F x velocity = mav
But this is just

Power = mav,
so that for the moving car we have,

acceleration = Power / (mass x speed)

This is the equation you need to work with. Now to make all the units work out
correctly in the English pound - foot system, you need to express

Power = Horsepower x 550 ft-lb/sec
Mass = Weight (in pounds) / (32 ft / sec^2)
speed is in feet / sec
acceleration will then be in feet / sec^2

Hope this helps.

Frank

You're getting things mess up.

T = Fd. F is perpendicular to d. This is a twisting motion, as in angular force.
F = ma. a is linear acceleration. You can't just plug those 2 equations together and
solve them. You need to deal T equation with angular acceleration, not linear.
Basically, you need more equations to translate those 2.

That site sucks. First it says the Mustang engine is not good for pulling a truck
because it lacks torque. Then it contradict its self by proving that the Mustang's
engine could put out as much torque as the diesel engine, through the use of gear.
And then it says that the Mustang's engine won't last pulling a truck.

If the author had a bit of brain cell, he would forget his argument about torque and
just conclude that the Mustang's engine could pull as well as the diesel engine, but
that it won't last as long operating full time at full load at 5k rpm. It has nothing
to do with torque, just pure power.

As I said before, massive recital of myth does not make it a fact.

Harry Cox wrote:

> As you state, F = ma (force equals mass times acceleration)
>
> So, a = F/m (acceleration equals force divided by mass).
>
> To accelerate the car, we need F (force).
>
> Torque is force times distance. T = Fd
>
> Solving for F and plugging that into our acceleration equation, we get
>
> a = T/d/m (acceleration equals torque divided by distance divided by
> mass).
>
> For your particular car, the distance and the mass don't change. Hence
> acceleration depends on torque only.
>
> As the car goes faster and faster, you need horsepower to maintain
> that torque at the higher RPMs.
>
> There's some interesting background at
> http://science.howstuffworks.com/fpte.htm.

In rec.autos.makers.honda Hawaii_SE-R > wrote:
> I highly doubt you could produce more torque than the VQ35DE on your
> bicycle.

More than the Honda anyway. What was that, 214 lb/ft? ( what's a "tq" ?).
Assuming the pedal on the bicycle is one foot long, which it might not be,
and that I weigh 214 pounds, all I have to do is stand on the pedal.
214 lbs/ft of torque. I could get more by pulling up on the handlebar as I
pressed down on the pedal.
How many horespower is that? If I could pedal the bicycle at that rate for
one full second it would be 214/550 = .38 hp.

---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5

(ravelation) wrote in news:15540-41B7266E-
:

>
> (Sean*Dinh)
> wrote:
>
>>You are so wrong. Horsepower is
> >everything. Since the Altima has a 3.5 L
> >vs the Accord's 3.0 L, the Altima has
> >more low end power. It would take off at
> >the line faster.
>
> I wonder what the difference is in each car's gas mileage/gallon. Did
> Honda manufacture the Accord with fuel saving in mind?
>
> My husband's new TL gets really good gas mileage and is fast to boot.
> I'm still trying to figure out how they've achieved both!
>
>

i you buy a 3.0 v6 accord don't talk about the milage/gallon
otherwise you would drive a 2.0 i-vtec accord (the european one)

marcel

wrote:
> In rec.autos.makers.honda Hawaii_SE-R > wrote:
>
>>I highly doubt you could produce more torque than the VQ35DE on your
>>bicycle.
>
>
> More than the Honda anyway. What was that, 214 lb/ft? ( what's a "tq" ?).
> Assuming the pedal on the bicycle is one foot long, which it might not be,
> and that I weigh 214 pounds, all I have to do is stand on the pedal.
> 214 lbs/ft of torque. I could get more by pulling up on the handlebar as I
> pressed down on the pedal.
> How many horespower is that? If I could pedal the bicycle at that rate for
> one full second it would be 214/550 = .38 hp.
>
> ---
> Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>
Fianlly, someone who understands the difference between torque and
horsepower!

--
Rob Munach, PE
Excel Engineering
PO Box 1264
Carrboro, NC 27510

I have a 2004 EX sedan with V6 and love it. The engine/transmission combo is
fantastic and the suspension/handling is superb. I would not put too much
stock into performance numbers unless they consistently show a major gap in
performance from a number of reliable sources. The cars are very evenly
matched and to obsess about a silly possible slight difference in 0 - 60 is
silly. Are you expecting to get into lot of drag races with Altimas? I don't
think the Altima V-6 is exactly cheap any more and I consider their rear end
to be butt ugly. If performance is that important then get a new Mustang GT
for around the same or less money. --- Steve


"tony kujawa" > wrote in message
...
> On paper these should have pretty even performance #'s but the Altima
> beats
> the Accord soundly when comparing auto trannys, and trounces it when it
> comes to the 6 speed. Were talking 1/2 second in the quarter and 0-60 in
> the autos, and a full second for the 6 speed. What gives with the Honda?
> Either the hp #'s are off or it is a lot heavier than the Altima. And why
> oh why doesn't Honda make the 4 door and an LX version of a coupe in the 6
> speed? I really want a Honda due to the high resale and past ownership,
> but
> have had an older Maxima that I loved. The new Altima is very nice
> looking,
> but I've heard the interiors are cheap. Now I haven't driven either of
> them
> yet, so I guess I should really save judgement until then. What are your
> thoughts?
>
>