Do Diesel engines have the mid-range performance avantage over petrol alternatives?

Am trying to find that clip from 5th gear comparing the petrol and diesel versions of some sort of Vauxhall..


Oh come on, 4th gear?! Not real world testing..
 
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NickXX said:
Not so sure about this, the 330d will pull to 80mph in 3rd, dropping to 2nd in the 330i would surely mean a gearchange mid-overtake?
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indeed, mine has plenty of pull in 3rd, though tbh i never need to plant the foot so much that it drops to 3rd for me!
 
[TW]Fox;13527448 said:
I wonder why the 330d takes so much longer to get to 100 then....
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3 gearchanges to get to 100 rather than 2? In real world terms, the power and gearing of the 330d is more usable than the 330i.

At the end of the day, the 330d will pull hard from 40 through to 80mph in 3rd gear which is surely going to be 95% of overtaking situations. The 330i needs a gearchange at 65 if you're keeping it on the boil.
 
This probably explains it better:

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Peak torque stays above 300Nm from 1,750 until the end of the rev range - which in 3rd is around 80mph.
 
Yay a remapped car with 25% more torque than standard. Torque tails off at about 3500rpm. Giving you what, 1500rpm to play with? Don't get me wrong, it's not slow, infact, it's pretty quick, but the petrol version is quicker.
 
[TW]Fox;13527570 said:
Yay a remapped car with 25% more torque than standard. Torque tails off at about 3500rpm. Giving you what, 1500rpm to play with? Don't get me wrong, it's not slow, infact, it's pretty quick, but the petrol version is quicker.
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So what, a remap costs £250 and transforms the car - this is a negliable amount when you've spent in excess of £10k on the thing.

The torque tailing off is irrelevant as you still have over 300Nm until you have to change gear - which in the case of 3rd is 80mph.

A 330i will get from 0-60 and 0-100 faster than a standard 330d, there's no doubt in my mind about that. However, you're still completely ignoring real-world performance and the fact that in most overtaking situations, the petrol will require an extra gearchange mid-overtake whereas the diesel will not.

The miriad numbers in the back of Evo don't always tell the full story.
 
NickXX said:
The torque tailing off is irrelevant as you still have over 300Nm
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..... at the fly. How much of that is reaching the tarmac?

The miriad numbers in the back of Evo don't always tell the full story.
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No but regularly driving an x30d and an x30i back to back does. I bet you can't remember the last time you overtook in a 330i :p
 
[TW]Fox;13527633 said:
No but regularly driving an x30d and an x30i back to back does.
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the x30i and x30d have a significant power difference though..
193bhp to 231 iirc?

nick's argument is valid in cars which have the same power output
eg golf 1.8t vs a 1.9 150 tdi perhaps?
 
mjt said:
the x30i and x30d have a significant power difference though..
193 to 231 iirc?
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Exactly, hence the greater performance in most circumstances from the petrol car - yet they are the models that sat beside each other in the range. The ones you compared, you either bought the diesel or the petrol. You didnt walk in and ask for a '230bhp BMW please', you wanted either the 330 petrol or the 330 diesel.

The current 330d is now 245bhp and is a pretty quick car. A great car, infact. Unfortunately the 330i is now 272bhp..

How often do a manufacturers petrol and diesel equivilents have the same power output? Very rarely. You didnt pay any extra for this extra power output from the 3 litre so it's not relevent.
 
[TW]Fox;13527655 said:
How often do a manufacturers petrol and diesel equivilents have the same power output? Very rarely. You didnt pay any extra for this extra power output from the 3 litre so it's not relevent.
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surely it is relevant though. if you compare a more powerful petrol to a diesel, then clearly the petrol will win any power-based argument? :confused:

if you take the 120bhp mini against the 110bhp diesel like in the op, then the results are not so clear cut..
 
[TW]Fox;13527694 said:
Exactly so the petrol version is the better car in terms of performance. Which is my point.
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no, your point is that a petrol version with more power than the diesel version is a better car.

why not compare an e46 330d to a 325i?
 
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