Diesel cash guzzlers: It can take 28 years for them to be cost-effective

Dolph said:
No, but it tends to negate the 'diesel advantage' of lazy drivers not changing the gear to the best one for acceleration at a given time.

When comparing through gear acceleration times, diesels tend not to win, it's only when you're comparing low rev acceleration that diesel wins.
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You're spot on, in that diesels have narrow powerbands compared to petrols. Clarkson summed it up well when he described them as all the power coming in suddenly then shortly afterwards it's gone. That said, while diesels will never rev like a petrol lump will they are getting better. In this respect I couldn't argue with you (although it wouldn't be such a waste of a sunday afternoon) so I should clarify my original point which was by using the term "ingear acceleration" in this example I was aiming it more to acceleration times that do not involve a standing start.
 
Overlag said:
just change down 2 gears and go whats the problem?
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Time.
It can be an issue. Not always, but the fractions of a second involved could mean accident or no accident.
Overlag said:
oh and why would you be driving a petrol at 1000rpm?
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You wouldn't be, but the last time I drove a VTEC engined car the power cam didn't come in anywhere near 2000-2500RPM.
 
Howard said:
I thought that might be the case.

If you must know, I've been driving since october 2004, and I know what the term means, I just think terms such as 'mid-range grunt/acceleration' make more sense :p

It was a semi-throwaway comment, not really designed to start a huge debate :)
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Don't worry mate, my next comment wasn't going to be along the lines of "I'm considerably more blah blah blah than you".....apologies if you thought that's what was coming next.
 
The_Dark_Side said:
While 99% of the time I will agree with you on the above all day long, we're human beings and as such we make mistakes.
You can be caught off guard, sometimes for no fault of your own.
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That's an argument for banning all the underpowered, underbraked, poorly handling shopping cars then :D
 
Dolph said:
That's an argument for banning all the underpowered, underbraked, poorly handling shopping cars then :D
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LOL, still Mr. twisty-turny I see?

The driver is at fault, not the car, as well you know ;)

I'm unsure I agree with your underbraked comment though. Is there a specific vehicle you have in mind?
 
The_Dark_Side said:
LOL, still Mr. twisty-turny I see?

The driver is at fault, not the car, as well you know ;)

I'm unsure I agree with your underbraked comment though. Is there a specific vehicle you have in mind?
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Of course :)

Compare stopping distance of performance cars with base models, and most of them appear under braked... Mind you, most of them are underpowered to in terms of having decent reserve acceleration as well.

And we won't even start on SUV handling... :D
 
The_Dark_Side said:
Time.
It can be an issue. Not always, but the fractions of a second involved could mean accident or no accident.

You wouldn't be, but the last time I drove a VTEC engined car the power cam didn't come in anywhere near 2000-2500RPM.
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your the one that said 1000rpm.... changing down takes oh..... 2 seconds? read the road better and you will be fine. Its just pure laziness (as fox says)
 
Overlag said:
your the one that said 1000rpm
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Perhaps some type of contact lenses are appropriate for you?
The_Dark_Side said:
Try doing the above in a VTEC when you're somewhere around 1000/1500 RPM away from the power cam and you'll see what I mean.
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If you're 1000RPM away from the power cam in a VTEC engine, you can easily be still somewhere around 3000-3500RPM.
 
The_Dark_Side said:
Quick in gear times are extremely relevant in situations like this. Try doing the above in a VTEC when you're somewhere around 1000/1500 RPM away from the power cam and you'll see what I mean.
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You would never be at 1000rpm in a Vtec car though.

Crusing along is 3-4k. Plus with no turbo lag you have instant response.
 
The torque curve for a VTEC engine is pretty much flat, so the power cam doesn't (shouldn't) make much difference. What all VTEC engines thrive on is revs...
 
The_Dark_Side said:
Where in the rev range does the power cam come in on the Honda/Toyota VTEC-type engines?
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Typical changeover is around 5500-6200 depending on engine, but don't be fooled in thinking they have nothing below that, short gearing and high compression makes pickup pretty decent.

For example my engine from 2,500rpm still pulls cleanly, its still hits 150hp by 6000rpm in standard mode, then it goes nuts into race mode.

Its certainly quicker than most cars on the road lol
 
Simon said:
Typical changeover is around 5500-6200 depending on engine, but don't be fooled in thinking they have nothing below that, short gearing and high compression makes pickup pretty decent.

For example my engine from 2,500rpm still pulls cleanly, its still hits 150hp by 6000rpm in standard mode, then it goes nuts into race mode.

Its certainly quicker than most cars on the road lol
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No mate I'm not suggesting that it's all or nothing, all I'm saying is that on a more mundane VTEC engined car you can catch it off the boil if you suddenly demand a lot more power when you're lower down the rev range.
 
The_Dark_Side said:
No mate I'm not suggesting that it's all or nothing, all I'm saying is that on a more mundane VTEC engined car you can catch it off the boil if you suddenly demand a lot more power when you're lower down the rev range.
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Just like any petrol car though, although having vtec is an advantage rather than disadvantage.
 
Simon said:
Some arent flat :D
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You're (assuming you still have the S2k) is a little different as it's a performance car.....but Honda fit the VTEC system to cars that are much more ordinary as well. Yours is built to be pedalled quickly, but on regular cars VTEC is an attempt to give the best of both worlds (Not trying to teach you to suck eggs here as I'm more than aware of your field of expertise) and as such if you're on the "economy" cam and still 1000rmp+ away from the power cam you can catch the motor off guard.
 
The_Dark_Side said:
You're (assuming you still have the S2k) is a little different as it's a performance car.....but Honda fit the VTEC system to cars that are much more ordinary as well. Yours is built to be pedalled quickly, but on regular cars VTEC is an attempt to give the best of both worlds (Not trying to teach you to suck eggs here as I'm more than aware of your field of expertise) and as such if you're on the "economy" cam and still 1000rmp+ away from the power cam you can catch the motor off guard.
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I know, all I said was that some aren't flat.

VTEC economy cams also have slightly different lift on many engines, this promotes swirl and better combustion efficiency.
 
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