[Magna]

I have a 2000 323i with Sport Package and it's a March 2000 production, so I am pretty sure it has the mechanical trottle. I drove an old Porsche 911 and all I had to do was tap the trottle and the revs went up instantly (absolutely no lag), then again the revs didn't "stick" or "stay" and the revs went down almost as fast as they went up. On my BMW 323i to match revs during a downshift, I have to "more than blip" the trottle (I need to hold the trottle in an extra moment) to get the revs up. Then again, the revs "stay up" or "stick" longer than on the Porsche 911.

Questions: Anybody else experiencing this? Is this normal? Is this what the people with trottle by wire are complaining about? Or is the lag longer with trottle by wire?

Out of curiousity, why did the Porsche respond so instantly compared to my BMW? Perhaps it was engineered that way. Also, the revs wouldn't stay up as long as the BMW's. Anybody know how they engineered that?

Thanks for any info.

 

[Kaz]

Uusally this means that the more 'responsive' drivetrain has a lighter flywheel or otherwise carries less mechanical momentum, all others being equal.

Between a 911 and a E46, this sounds likely to me.

 

[Mystikal]

Also, the ECU is tuned to produce lower emissions, so the quick change of revs is slowed down significantly for less unburnt CO2 coming out the pipe. Something like that. Methinks the Shark Injector could help this problem a bit.

BTW, I too have a 3/2000 production 323i SP :thumb:

 

[nate]

Mystikal is right, the reason is the ECU is letting RPMs drop slowly in order to raise fuel emissions....

Gotta meet CAFE standards