[AlBoston]

So I order my new 535xdrive with the sport auto trans, but am reconsidering my choice. I've read its just paddles and different software, true? Does it include revmatch downshifting? I forgot to try this on my test drive.

[pharding]

That the SAT is just paddle shifters is a ridiculous urban legend that has been beaten to death here. Please look at the relevant threads using the search function. SAT is much more and is a great option. Downshifting is amazing for an automatic transmission, much better than the E60 sport tranny.

[grimlock]

'different software' can mean a lot.. as the software controls all the aspects of a transmission..
meaning if the paddles were to dissappear on a Sport auto car, it would still drive differently in normal use because the software differs, but how exactly and how large the difference, is a matter of contention ...

I rarely use kickdown, so i don't know how well it revmatches, or what exactly this means, but the Sport auto in Manual shifting mode is HEAVEN ... can't comment on Manual mode with Normal auto though

[AlBoston]

I did look this up via the search tool but didn't come up with any concrete answers about rev matching downshifts.

[Jon D]

Originally Posted by AlBoston

I did look this up via the search tool but didn't come up with any concrete answers about rev matching downshifts.

It's the same as momentarily blipping the throttle with a manual gearbox between downshifts to increase the RPM to match the road speed. That way you get jerk free downshifts and that's exactly what you get with the sport auto.

[grimlock]

Originally Posted by Jon D

It's the same as momentarily blipping the throttle with a manual gearbox between downshifts to increase the RPM to match the road speed. That way you get jerk free downshifts and that's exactly what you get with the sport auto.

oh.. i get it.. its called 're-constitute oil' in chinese =increase the gas/throttle to the amount required to maintain the same rpm in a lower gear

i don't pay attention to how well the f10/sport auto does this, im too busy enjoying the 8speed transmission+N52B30 engine in 'M' mode

[grimlock]

actually the amount of revmatching does seem to vary.. i got a very obvious (tiny) roar the other day when I downshifted in 'M' on Sport (non-tranmission) but today I didn't notice anything .. I would say it does vary alot, depending on the rpm, gear, speed ...
I need to start driving it in Sport transmission mode.. and pay attention to this .. but its hard to in the city.. i try my best

[Jon D]

Originally Posted by grimlock

oh.. i get it.. its called 're-constitute oil' in chinese =increase the gas/throttle to the amount required to maintain the same rpm in a lower gear

Not quite; the revs increase to match the road speed and as they decay the gearbox slows the car through the downshifts.