JerryU

Bill has said that before. Can understand when he is Tracking!

But I never use ECO and now am driving my Grand Sport in Sport Mode with the software upgrade. But still have NPP in Always Track Mode.

Below about 1700 rpm the butterflies are closed. Big help on the Interstate as in 7th below 78 mph (where I have cruise control set) they are closed and no drown. When I take the 2 mile narrow trusty 25 mph road from my home to the highway I pass a friend’s house. There is a sharpe turn near her home and in the low gear I am usually in, getting the engine warm and keeping a low speed, I am right on the edge. If I give it a bit more gas they open. She accuses me of “Gunning” the car by her home- in a laughing way!

Previously when I checked, in Touring they open at about 2500 rpm.

mdolandese

Thank You Appreciate it

faninc

I have 2019 GS, auto trans. If I do fuse pull and need to drive out quiet in the mornings is it true by putting car in eco mode the flaps for 4 cylinder mode will help noise level? Or will car be in v8 mode until cruising long enough to engage 4 cylinder mode?

Thanks

JerryU

i^^^
IF you pull the fuse there is no electricity to turn the motors to close the butterflies in the two outer exhausts pipes. How could they close?

Perhaps you already did but set the car up as NPP always in Track mode regardless of Driving Mode set. That gets the butterflies open at ~1700 rpm versus ~2500 to 2700 rpm if driving in Touring.

Good enough for me and no drone on the Interstate. If not loud over a wider range install a Mild to Wild kit.

faninc

My understanding is different fuse for 4 cylinder baffles so basis for my question about eco mode on auto trans.

phalse

dumb question.. my M7 2LT doesnt have the npp exhaust, so... whats the point of the exhaust settings in the vehicle config? it offers the usual choice of track, sport etc but is it really doing anything to the exhaust?

JerryU

First, unlike NPP, those butterflies BEFORE the mufflers do not full close! If they did the engine would shut off!

Second pulling that fuse will trip a CEL! It has a feedback circuit that would see they are not operating. It would also do nothing for the sound in other than 4 cylinder mode as in V8 mode they are fully open.

The reason that they exist is so the car doesn't sound like a V8 missing on 4 cylinders! What would you accomplish if you could keep them open? Nothing to do with sound other when in 4 cylinder mode and then NOT a better sound.

JerryU

There is a footnote on some of the tables for exhaust that says, "if so equipped." It's the same with ride, if you don't have MRC no change.

What does change is Steering stiffness, Throttle tip in, and Nannie thresholds. That is important as in Weather mode it will prevent spinning the tires sooner.

BJ67

Just pull the fuse while the car is not running.