[SomeRandomer123]

Just seen the first acceleration video of the M550dx from F10 post and wow! Sounds ace, goes like hell and revs to over 5500rpm! So where is the rev limiter? On our mere mortal N57's, the limiter is situated at 5000rpm.

[SomeRandomer123]

Found out the rev-limiter is at 5400rpm, despite seeing the needle hit 5600 in a 1st gear "manual" launch. Must have been the inertia.

[maswastage]

One of the first things that caught my eye about the M550dx was how high its engine revs. Interestingly, according to the specs, it still produces peak power between 4000 and 4,400 rpm, the same as our engines. I wonder if forcing it to shift at 4500 rpm, the same as our cars, will actually lead to faster acceleration.

[SomeRandomer123]

Originally Posted by maswastage

One of the first things that caught my eye about the M550dx was how high its engine revs. Interestingly, according to the specs, it still produces peak power between 4000 and 4,400 rpm, the same as our engines. I wonder if forcing it to shift at 4500 rpm, the same as our cars, will actually lead to faster acceleration.

Yeah I thought that. Possibly, but you've got to think where the next gear is going to pick up. Being the 8spd ZF though, it should have relatively short ratios so you could be right!

[DnA Diesel]

What we need here (or in any case, gas/diesel alike) to determine optimized acceleration is to plot rear wheel torque against road speed for all gears then assess the intersection of each gear plotted to the next to see at what point a shift will result in maximized area under the curve. With the narrower ratios of the 8HP70, I too would think that going right to the red-line may actually cause more of a drop in rear wheel torque available than dropping down solidly into that much stronger, flat-rated mountain top of torque in a numerically taller gear.

Anyone have a torque plot of the 50d N57?

Regards
D.

[Thud]

It does sound good. I wonder if that's the actual engine sound, or if it's electronically generated through the speakers like the M5.

[SomeRandomer123]

Originally Posted by Thud

It does sound good. I wonder if that's the actual engine sound, or if it's electronically generated through the speakers like the M5.

It does have active sound like the M5 but does it really sound that dissimilar from our cars? No!

[SomeRandomer123]

Originally Posted by DnA Diesel

What we need here (or in any case, gas/diesel alike) to determine optimized acceleration is to plot rear wheel torque against road speed for all gears then assess the intersection of each gear plotted to the next to see at what point a shift will result in maximized area under the curve. With the narrower ratios of the 8HP70, I too would think that going right to the red-line may actually cause more of a drop in rear wheel torque available than dropping down solidly into that much stronger, flat-rated mountain top of torque in a numerically taller gear.

Anyone have a torque plot of the 50d N57?

Regards
D.

This is the best I can do:
Power and Torque curve for the 50d.

[cssnms]

Engine animation,,, very cool.

[Zechariaha]

wow cool vid.

[DnA Diesel]

Originally Posted by SomeRandomer123

This is the best I can do:
Power and Torque curve for the 50d.

Thanks, 123! More to follow....

[Quasimodem]

Originally Posted by cssnms

Engine animation,,, very cool.

Seems pretty sad that the triturbo is going first into every BMW except the three series.