Allymunro

In the UK the 2.5L engine is offered as a 177HP or 218HP (model 523 or 525) Extra cost ?1600 for the 218HP, about 5% of the total car cost.

Can, and should I justify the additional 5% cost for the extra HP?

tegel

I would put that money on equipment, but that's me. The 523i engine is very smooth and well balanced.

/M

new-kid

Don't just look at the bhp figure - also compare the torque figure and the rpm at which they occur. These four figures will give a much more balanced view of the real life performance difference.

(Then ignore the lot and get a 530d or 535d ! )

Allymunro

Torque figures for the 523 (177HP) are 230 Nm at 3500rpm and 250 Nm at 2750 rpm for the 525 (218HP)

Not quite sure what this really means. Why are torque figures quoed at different rpm's?

tegel

...and for the 520d (163HP) it's 340Nm at 2000rpm. Drove it again now, very impressive, will order one this week if I can get a fair price from the dealer.

The torque peaks at different RPM:s depending on the engine character.

/M

PeterS

Torque is a measure of turning effort I think. The torque figures given above are the maximum, and the rpms given are the rpms at which the maximum torque is reached. This varies from engine to engine, which is why there are different rpms quoted for the two engines.

What the numbers above show is that the 525 generates 20Nm more torque (IMO useful but not that significant @ less than 10% more), but at 750rpm lower. This is quite a lot lower down the rev range, indicating that the engine has to be revved less for a given amount of 'push' to be generated. You'll have to rev the 523 more to generate the same amount of 'push' as the 525, so perhaps it will be less relaxing drive, and you might find yourself having to change gear more frequently (for example, when traffic slows on a motorway then speeds up, you are more likely to have to drop a gear or 2 to get decent acceleration in the 523i). That's my understanding at least, but I'm no expert...

HTH

Peter

PeterS

Thanks for the summary of how the 520d performs - I must try and get the dealer to lend me one, as I'd like to see what it's like. Certainly in the 3'er it performs very well, and I don't think the 5 is that much heavier

Peter

needforspeed

Torque and horsepower are different ways of expressing power. Torque is a twisting force and hp is a way of considering power as a linear force. Hp = torque at 5250rpm (always)

High Torque = Feeling of Speed

Lots of torque at High RPMs = VERY FAST CAR = because of GEARING

The peak figures for HP and Torque are only part of the story as you need to look at the 'torque curve' for all the rev range.

Peak torque in the 525 is higher and available sooner than in the 523 - which will give better 0-60 sprint times. It's going to stay that way right up until the limit

Better still get a 530d (500nm) he he he he

PeterS

Why stop there

Peter

new-kid

On reflection I was thinking - why buy a new 523 or 525. In spite of what the dealer tells you, the depreciation will by eye watering (particularly on all the extras, which have minimal resale value).

A one year old 530d or 530i would be a much better bet financially - and more fun.