Why is extra horsepower so expensive?

[TwinExit]

Danxr46 said:

You say tail off at 4500rpm
But that’s basically near it’s limit so therefore it isn’t a narrow band of torque in terms of diesel, yes a type r for example it is but while that may have a longer range of rpm, when it comes down to it the torque that car produces, as a car/engine whatever is it and doesn’t produce near as much.

Now the D has been mapped itnoroduces it’s torque throughout the Rev range for slightly longer and I didn’t realise you were there when I got my car mapped and on a rolling road and told the % of inaccuracies however it is making (actual) not claimed, 291HP.

This maybe somewhat on avg 60HP (claimed ford sales men) short of the NEW focus RS however it’s advantage comes initially from its AWD. I have taken the times from similar output 330D cars which run around or just shy to .3/.4 of a sec to 100 which I wouldn’t say is really a difference.

In particular as the RS is manual only then it would take some s*** hot driver to get the “quoted” figure from ford against the actual figure from numerous cars data. Either way it was just a example where torque is more in diesel compared to HP chasing figures in petrols. It does just come down to what individuals want and what suits the engine type better.

I am not sure which 'Type R' you are referencing. If it is the NA Hondas from 10-20 years ago, the maths and real-world acceleration evidence will back your re-mapped 330D being a faster car - which isn't a shock as the old Type-Rs only output 140-160 lbs/ft torque upto 8k rpm, where as you have 360-420 lbs/ft despite only having upto 4.5k rpm to play with.

The maths do not add up when you quote re-mapped 330D cars against the new Civic Type R or the Focus RS, which outputs 260-300+ lbs/ft depending where you are in the mid or upper rev range, and they rev to 7k RPM.

Even if we discount the launch/driver ability, the 60-100 mph times of a turbo CTR falls between 6.7-7.2 secs, and the Focus RS around 7.0-7.6 both with one or two gear shifts in between.

A re-mapped 330D using ONLY 4th gear we're in the mid 7 second range, and using 3rd & 4th will be high 7's to low 8s, still very fast on the road (prob need to look these up on youtube), but despite having much more torque, the 330D is still slower ...


Torque output at the engine only really determines acceleration when you factor in the operational RPM range of the motor, the higher the RPMs, the shorter the gear ratio (higher torque multiplication) you can apply tractive force on the road. So whilst turbo'd diesels kick out impressive torque numbers, these numbers are cancelled out by their limited RPM range.

Edited by TwinExit on Thursday 1st March 09:48

[SonicShadow]

A few relevant videos for your enjoyment:

Horsepower vs Torque - A Simple Explanation
https://www.youtube.com/watch?v=u-MH4sf5xkY

Horsepower vs Torque - Formula 1 vs NASCAR
https://www.youtube.com/watch?v=CxK0x7AE3s8

How Horsepower Affects Acceleration
https://www.youtube.com/watch?v=chbjcbmaVDc

When To Shift Gears For The Fastest Acceleration
https://www.youtube.com/watch?v=zZBqb0ZJSwU

[Danxr46]

TwinExit said:

Danxr46 said:

You say tail off at 4500rpm
But that’s basically near it’s limit so therefore it isn’t a narrow band of torque in terms of diesel, yes a type r for example it is but while that may have a longer range of rpm, when it comes down to it the torque that car produces, as a car/engine whatever is it and doesn’t produce near as much.

Now the D has been mapped itnoroduces it’s torque throughout the Rev range for slightly longer and I didn’t realise you were there when I got my car mapped and on a rolling road and told the % of inaccuracies however it is making (actual) not claimed, 291HP.

This maybe somewhat on avg 60HP (claimed ford sales men) short of the NEW focus RS however it’s advantage comes initially from its AWD. I have taken the times from similar output 330D cars which run around or just shy to .3/.4 of a sec to 100 which I wouldn’t say is really a difference.

In particular as the RS is manual only then it would take some s*** hot driver to get the “quoted” figure from ford against the actual figure from numerous cars data. Either way it was just a example where torque is more in diesel compared to HP chasing figures in petrols. It does just come down to what individuals want and what suits the engine type better.

I am not sure which 'Type R' you are referencing. If it is the NA Hondas from 10-20 years ago, the maths and real-world acceleration evidence will back your re-mapped 330D being a faster car - which isn't a shock as the old Type-Rs only output 140-160 lbs/ft torque upto 8k rpm, where as you have 360-420 lbs/ft despite only having upto 4.5k rpm to play with.

The maths do not add up when you quote re-mapped 330D cars against the new Civic Type R or the Focus RS, which outputs 260-300+ lbs/ft depending where you are in the mid or upper rev range, and they rev to 7k RPM.

Even if we discount the launch/driver ability, the 60-100 mph times of a turbo CTR falls between 6.7-7.2 secs, and the Focus RS around 7.0-7.6 both with one or two gear shifts in between.

A re-mapped 330D using ONLY 4th gear we're in the mid 7 second range, and using 3rd & 4th will be high 7's to low 8s, still very fast on the road (prob need to look these up on youtube), but despite having much more torque, the 330D is still slower ...


Torque output at the engine only really determines acceleration when you factor in the operational RPM range of the motor, the higher the RPMs, the shorter the gear ratio (higher torque multiplication) you can apply tractive force on the road. So whilst turbo'd diesels kick out impressive torque numbers, these numbers are cancelled out by their limited RPM range.

Edited by TwinExit on Thursday 1st March 09:48

Missing the point of what I said meant originally which is being in a diesel I would be more into torque figures etc, not entirely but more so. Neither of the newer cars are that more powerful and potent that a driver in one would pull away easily, lose or disappear from a mapped 330d not one bit. Fractions of a second maybe the difference in times but that’s at the best of times each time etc. Ive not once said that the diesel is faster but that it would basically keep with one and the times from the new rs fro example it only achieves a good 60 time due to the traction but higher up for the car it is is pants. The mk2 previous still that isn’t as fast still but that’s not the point I originally made.

[Toltec]

SonicShadow said:

When To Shift Gears For The Fastest Acceleration
https://www.youtube.com/watch?v=zZBqb0ZJSwU

That is a really long winded way of saying rev to the redline unless you are making less power there than the rpm you shift to in the next gear.

I'd guess that for most N/A petrol engines in cars changing at the red line is the correct place, I think it will be turbo petrol and diesel engines where this may change, particularly modern petrol engines where the turbo is sized for low rpm spool and low lag.


This Impreza you would rev out-



This Impreza you would be looking to change up probably between 5500 and 6000 rpm

[TwinExit]

Danxr46 said:

Missing the point of what I said meant originally which is being in a diesel I would be more into torque figures etc, not entirely but more so. Neither of the newer cars are that more powerful and potent that a driver in one would pull away easily, lose or disappear from a mapped 330d not one bit. Fractions of a second maybe the difference in times but that’s at the best of times each time etc. Ive not once said that the diesel is faster but that it would basically keep with one and the times from the new rs fro example it only achieves a good 60 time due to the traction but higher up for the car it is is pants. The mk2 previous still that isn’t as fast still but that’s not the point I originally made.

I am not missing any point.

Torque is torque, horse power is horsepower regardless of what fuel you are using.

The fact remains is your higher torque output was still not sufficient to out accelerate a car with less torque, this is due to your lack of RPM range and as a result you needed to use a taller gear (up shift) to accelerate otherwise you will hit your 4xxx rpm rev limiter.

The Focus RS is quicker than your re-mapped 330D not because its more horsepower or less horsepower, it is because thanks to its wider and higher RPM band, the motor puts down a bit more torque once multiplicated to the wheels by using a much lower gear than yours.

Edited by TwinExit on Thursday 1st March 12:42

[otolith]

I thought the invincibility of the remapped 330d was a pistonheads trope consigned to the past.

[Danxr46]

TwinExit said:

Danxr46 said:

Missing the point of what I said meant originally which is being in a diesel I would be more into torque figures etc, not entirely but more so. Neither of the newer cars are that more powerful and potent that a driver in one would pull away easily, lose or disappear from a mapped 330d not one bit. Fractions of a second maybe the difference in times but that’s at the best of times each time etc. Ive not once said that the diesel is faster but that it would basically keep with one and the times from the new rs fro example it only achieves a good 60 time due to the traction but higher up for the car it is is pants. The mk2 previous still that isn’t as fast still but that’s not the point I originally made.

I am not missing any point.

Torque is torque, horse power is horsepower regardless of what fuel you are using.

The fact remains is your higher torque output was still not sufficient to out accelerate a car with less torque, this is due to your lack of RPM range and as a result you needed to use a taller gear (up shift) to accelerate otherwise you will hit your 4xxx rpm rev limiter.

The Focus RS is quicker than your re-mapped 330D not because its more horsepower or less horsepower, it is because thanks to its wider and higher RPM band, the motor puts down a bit more torque once multiplicated to the wheels by using a much lower gear than yours.

Edited by TwinExit on Thursday 1st March 12:42

The point from what I was speaking about myself having a diesel I would be chasing more torque etc is my point so yes !! I know torque is torque etc and so on but it’s applicable in different cars engine types etc. The RS isn’t exactly quicker. If your talking fractions of a second yes but real world is no

[Danxr46]

Okay so real world times and speeds..... autoexpress timed the type r 0-60 of 6.1 and 30-50 of 2.4 quickest. My actual times were clocked at 5.8 and 2.2 alike. 50-70 was clocked at 4.1 and mine was 3.0secs. In gear that torque is making a difference.

[TheDrBrian]

Ok I’ve got in-gear , all need is real world and I’ve got bingo.

[TwinExit]

Danxr46 said:

The point from what I was speaking about myself having a diesel I would be chasing more torque etc is my point so yes !! I know torque is torque etc and so on but it’s applicable in different cars engine types etc. The RS isn’t exactly quicker. If your talking fractions of a second yes but real world is no

The RS is measurably quicker, despite the massive torque deficit from the motor.

I am not arguing about what is quicker - the facts speaks for themselves, I am just disproving your notion that a car with less torque than yours are 'gutless' when the reality is when measured they out accelerate your car with less motor torque.

Danxr46 said:

Okay so real world times and speeds..... autoexpress timed the type r 0-60 of 6.1 and 30-50 of 2.4 quickest. My actual times were clocked at 5.8 and 2.2 alike. 50-70 was clocked at 4.1 and mine was 3.0secs. In gear that torque is making a difference.

At 30-50 and 50-70 mph, the Type R has to shift gear, costing it atleast 0.5 seconds, additionally the times are/should be measured with GPS verified speed and not the speedometer.

Your 330D would do 30-50 in 2nd and 50-70 in 3rd - so no gear shift to delay the acceleration.

Also has this been tested with GPS speed or did you use a stop watch whilst watching your dashboard? BMW speedos are well known to over read between 5-10 mph over indicated speed.

Edited by TwinExit on Thursday 1st March 16:36

[Toltec]

TwinExit said:

BMW speedos are well known to over read between 5-10 mph over indicated speed.

Edited by TwinExit on Thursday 1st March 16:36

Of the three I have/had they over read by 2mph at 70 - 80 mph, though none burn diesel. My Smart roadster on the other hand reads about 8.5% high.

[InitialDave]

So what I'm reading is that I'd only give away a couple of tenths on an acceleration run in order to not have to drive a diesel? Deal!

[Prinny]

otolith said:

I thought the invincibility of the remapped 330d was a pistonheads trope consigned to the past.

Sadly, just like every other engine, downsizing is taking a toll.

In 2020, we will have a repeat of this thread with the legendary mapped 118d. Watch this space.

[Toltec]

Prinny said:

otolith said:

I thought the invincibility of the remapped 330d was a pistonheads trope consigned to the past.

Sadly, just like every other engine, downsizing is taking a toll.

In 2020, we will have a repeat of this thread with the legendary mapped 118d. Watch this space.

Already happened, it used to be a 335D didn't it?



Yes, yes, still a 3L I know.

[SonicShadow]

TwinExit said:

Also has this been tested with GPS speed or did you use a stop watch whilst watching your dashboard? BMW speedos are well known to over read between 5-10 mph over indicated speed.

One Mississippi, two Mississippi....

[Danxr46]

TwinExit said:

Danxr46 said:

The point from what I was speaking about myself having a diesel I would be chasing more torque etc is my point so yes !! I know torque is torque etc and so on but it’s applicable in different cars engine types etc. The RS isn’t exactly quicker. If your talking fractions of a second yes but real world is no

The RS is measurably quicker, despite the massive torque deficit from the motor.

I am not arguing about what is quicker - the facts speaks for themselves, I am just disproving your notion that a car with less torque than yours are 'gutless' when the reality is when measured they out accelerate your car with less motor torque.

Danxr46 said:

Okay so real world times and speeds..... autoexpress timed the type r 0-60 of 6.1 and 30-50 of 2.4 quickest. My actual times were clocked at 5.8 and 2.2 alike. 50-70 was clocked at 4.1 and mine was 3.0secs. In gear that torque is making a difference.

At 30-50 and 50-70 mph, the Type R has to shift gear, costing it atleast 0.5 seconds, additionally the times are/should be measured with GPS verified speed and not the speedometer.

Your 330D would do 30-50 in 2nd and 50-70 in 3rd - so no gear shift to delay the acceleration.

Also has this been tested with GPS speed or did you use a stop watch whilst watching your dashboard? BMW speedos are well known to over read between 5-10 mph over indicated speed.

Edited by TwinExit on Thursday 1st March 16:36

By gutless I meant the FN2 era etc and yes they do have less torque and no they aren’t quicker so he sthat proves what I’m meaning.

The times were measured on a GPS tracker on a disclosed runway track day last year. The cars also do have to change gear if they starting in 1st gear from a standstill but to get them speed times the cars can be in 2nd which isn’t bad at 30mph and they don’t have to change gear from 2nd to 3rd so that comment is disregarded straightaway. In gear they are not quite as fast fractionally. Plus some(not all) magazines normally test from a standstill and accelerate through which gives an advantage however if you want, that can compensate for the gear changes they ‘have’ to do. I’m not a full on diesel driver, I previously owned a gold mk5 R32 however the £500 a year to tax and half the fuel efficiency of the 330d it simply wasn’t worth it.

[TwinExit]

Danxr46 said:

By gutless I meant the FN2 era etc and yes they do have less torque and no they aren’t quicker so he sthat proves what I’m meaning.

The FN2 Civic is just a NA 2 litre car, with far less torque & HP than your 330D, even with the lower weight it is not a match for you in a straight line because of this. It is also no match for a car with the same torque and more HP, it is in some cases also no match for a car with more torque and less HP that revs up to the same RPM limit.

It doesn't matter what fuel it runs on, torque is torque, power is power.

Danxr46 said:

The times were measured on a GPS tracker on a disclosed runway track day last year. The cars also do have to change gear if they starting in 1st gear from a standstill but to get them speed times the cars can be in 2nd which isn’t bad at 30mph and they don’t have to change gear from 2nd to 3rd so that comment is disregarded straightaway.

You are not making much sense...

A E90 330D tops out at 25-30 mph (indicated mph) in 1st gear, so any true 30-50 mph test will always be done in at least 2nd gear for your car.

Watch every 0-xxx acceleration test and you'll find best times are achieved by shifting late as possible, that means the CTR or the Focus has reached a GPS speed of 31-32 MPH in 1st gear (34-36 mph indicated), so the 30-50 mph you extrapolated from some magazine test will likely be a result of the elapsed time when the car was at 30 MPH till it reached 50 MPH, there would have been a 1st->2nd shift during that time.

During 50-70 mph, both a CTR and Focus will use 2nd and 3rd, where as a 330D uses only 3rd gear.

Danxr46 said:

In gear they are not quite as fast fractionally. Plus some(not all) magazines normally test from a standstill and accelerate through which gives an advantage however if you want, that can compensate for the gear changes they ‘have’ to do. I’m not a full on diesel driver, I previously owned a gold mk5 R32 however the £500 a year to tax and half the fuel efficiency of the 330d it simply wasn’t worth it.

You have provided no evidence of any 'in-gear' performance of a FK8 CTR to form a valid conclusion, but I can provide you one where it did 30-50mph in 2.2 seconds in just 3RD GEAR.

http://www.autoexpress.co.uk/car-reviews/102646/hy...

Just what do you think it would do using only 2nd gear?? In either case, the CTR is still quicker 'in gear' than your 330D between 30-50 mph.

You were selective on the acceleration times so they flatter what your car claims to do, without regarding the gear and any shifts the CTR was under to support your claim that your remapped engine torque figures being the decisive metric.

Edited by TwinExit on Friday 2nd March 14:57

[TwinExit]

InitialDave said:

So what I'm reading is that I'd only give away a couple of tenths on an acceleration run in order to not have to drive a diesel? Deal!

No, if you are talking about a straight line blast from 0-100 mph, you will be around 1 maybe 2 seconds behind in acceleration.

And that's with a 'remapped' diesel.

What do you think will happen if a FRS or CTR was re-mapped? The gap will only increase.

[InitialDave]

TwinExit said:

No, if you are talking about a straight line blast from 0-100 mph, you will be around 1 maybe 2 seconds behind in acceleration.

And that's with a 'remapped' diesel.

What do you think will happen if a FRS or CTR was re-mapped? The gap will only increase.

I don't think you understood my comment.

I was humouring the idea that the diesel was faster by a couple of tenths to 60 in order to make a crack about it not being worth it because you're then having to drive a diesel.

[otolith]

Funnily enough, cars of similar performance can be miles apart if you choose a gear which is appropriate for one and inappropriate for the other. Who would have thought it?