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[Field Marshal Dr. Opti]

....
It does have 339 lb ft of torque by means of compensation though.

is that all 

http://www.parkers.co.uk/cars/reviews/facts-and-figures/mercedes-benz/r-class/estate-2006/33419/

376 lb ft.......Ah yes, the joy of big torque from a turbo diesel.


Only 220 BHP though......

[tigers_gonads]

Talking about diesels, always fancied a drive in one of those VW / Audi's with the V10 turbo diesel under the bonnet.  Over 700 nm of torque I believe 

[Field Marshal Dr. Opti]

Talking about diesels, always fancied a drive in one of those VW / Audi's with the V10 turbo diesel under the bonnet.  Over 700 nm of torque I believe 

In old money please, Mr Gonads.

Newton metres mean nothing to a sad old bastard like myself.

[tigers_gonads]

Talking about diesels, always fancied a drive in one of those VW / Audi's with the V10 turbo diesel under the bonnet.  Over 700 nm of torque I believe 

In old money please, Mr Gonads.

Newton metres mean nothing to a sad old bastard like myself.

Didn't know you was sad 

[Andy B]

....
Only 220 BHP though......

it's actually 224   ..... but I won't split hairs ..... not bad for a diseasal   

[05omegav6]

Talking about diesels, always fancied a drive in one of those VW / Audi's with the V10 turbo diesel under the bonnet.  Over 700 nm of torque I believe 

In old money please, Mr Gonads.

Newton metres mean nothing to a sad old bastard like myself.

Didn't know you was sad 

Not as sad as he'll be when Mrs Opti finds out 

[Sir Tigger KC]

Exhaust valve area will be proportional to the total inlet valve area so in this case, it will be equal to or slightly larger I would expect.

So what's the advantage of having two smaller inlet valves and one big exhaust valve, over 2 valves the same size?   

[chrisgixer]

Exhaust valve area will be proportional to the total inlet valve area so in this case, it will be equal to or slightly larger I would expect.

So what's the advantage of having two smaller inlet valves and one big exhaust valve, over 2 valves the same size?   

Guessing the two valves have a bigger over all area. There's a limit to the size of two holes within a single bore/head. So a way to get a bigger aperture is to have two holes.

Not sure if another valve would need another cam follower, and hence another cam to run it, due to space on a single cam. Probably.

[Entwood]

Exhaust valve area will be proportional to the total inlet valve area so in this case, it will be equal to or slightly larger I would expect.

So what's the advantage of having two smaller inlet valves and one big exhaust valve, over 2 valves the same size?   

My understanding is better fuel/air mixing within the cylinder, so giving a "better" spread of flame front / combustion, so increasing efficiency.

If all the fuel/air comes in through one valve it "sits" centrally in the cylinder, two valves ensures better "mixing".

This is all based on what I was told many years back when I asked the question .... no proof whatsoever so may well be totally wrong ... 

[Kevin Wood]

Exhaust valve area will be proportional to the total inlet valve area so in this case, it will be equal to or slightly larger I would expect.

So what's the advantage of having two smaller inlet valves and one big exhaust valve, over 2 valves the same size?   

Guessing the two valves have a bigger over all area. There's a limit to the size of two holes within a single bore/head. So a way to get a bigger aperture is to have two holes.

Yep, or more correctly, the cylinder of air gap that's exposed when the valve opens with a given lift is much bigger for a given space in the head when you fill that space with 2 small valves instead of one larger one. You also get better "swirl" which means better mixing of the fuel air mixture in the cylinder and more even filling.

Not sure if another valve would need another cam follower, and hence another cam to run it, due to space on a single cam. Probably.

Yep, it'll certainly need its' own lifter (hydraulic or manually shimmed) to set the clearance. Most have their own cam lobe.