[Dave07997S]

In sport+ mode does the exhaust open fully or still just partial. I definitely hear different exhaust tone from Sport to Sport+

[reallymarkedup]

The general consensus (which may be based on an exact number) is that they only open to 70%. That's why some people buy valve controllers.

[M_Power Rob]

Originally Posted by Dave07997S

In sport+ mode does the exhaust open fully or still just partial. I definitely hear different exhaust tone from Sport to Sport+

In sport plus it is open ~75% or so. You will need a valve controller to have the valve open fully.

[Southtown]

To add. I can’t tell much, if any, of a difference between the valves being open 75% vs fully open. The valve controller shines at keeping the valves fully open under light load and decels. Making the driving experience more enjoyable.

[ajaj96]

So I’ve noticed a few things with this. In sport plus when in gear they are definitely not fully open. However, in neutral they sound fully open but only when you start to give it some revs. In the 6MT, the vale’s feel about 50% open in neutral at idle. When you push in the clutch the vale’s open up to about 70%. When your in neutral and rev the engine, without pushing in the clutch, the vale’s seem to open fully while reving. Too much movement of the valves if you ask me. Just asking to break earlier than they should.

[M_Power Rob]

Originally Posted by ajaj96

So I’ve noticed a few things with this. In sport plus when in gear they are definitely not fully open. However, in neutral they sound fully open but only when you start to give it some revs. In the 6MT, the vale’s feel about 50% open in neutral at idle. When you push in the clutch the vale’s open up to about 70%. When your in neutral and rev the engine, without pushing in the clutch, the vale’s seem to open fully while reving. Too much movement of the valves if you ask me. Just asking to break earlier than they should.

You are just probably hearing an engine idle sound difference from engaging the clutch and car being in or out of gear. Without a valve controller, they are NEVER fully open.

[ajaj96]

Originally Posted by M_Power Rob

You are just probably hearing an engine idle sound difference from engaging the clutch and car being in or out of gear. Without a valve controller, they are NEVER fully open.

I dont think thats the case with this gen of M cars. They might not be fully open but im telling you if you sit there and be super ocd about listening to the difference in tone, the valves definetely open more in neutral when reving than when in gear accelerating. And also open up more when you push in the clutch vs sitting at idle in neutral.

[Carefree]

Originally Posted by ajaj96

I dont think thats the case with this gen of M cars. They might not be fully open but im telling you if you sit there and be super ocd about listening to the difference in tone, the valves definetely open more in neutral when reving than when in gear accelerating. And also open up more when you push in the clutch vs sitting at idle in neutral.

I think you’re hearing what you want to hear.

[Mr. Hankey]

Originally Posted by ajaj96

I dont think thats the case with this gen of M cars. They might not be fully open but im telling you if you sit there and be super ocd about listening to the difference in tone, the valves definetely open more in neutral when reving than when in gear accelerating. And also open up more when you push in the clutch vs sitting at idle in neutral.

This is exactly my finding. If I'm in neutral and push the clutch in the valves open up. Idle RPMs do not change. Let clutch out they close again. Weird. Maybe to make the car sound better when getting ready to take off

[BroDoze]

It’s so you can rev it up while parked / at a stop light and get the full volume / burbles. Not joking.

[Carefree]

Originally Posted by BroDoze

It’s so you can rev it up while parked / at a stop light and get the full volume / burbles. Not joking.

That’s an interesting possibility. If so, my “hearing what you want to hear” post is hogwash.

I hope a knowledgeable tech/vendor will comment on what owners are hearing.

[M_Power Rob]

Originally Posted by BroDoze

It’s so you can rev it up while parked / at a stop light and get the full volume / burbles. Not joking.

Huh? Not sure what this means nor what it has to do with the valves opening fully. They certainly dont have two different systems in place, one for the 6MT and one for the 8AT. BMW has never made their valved exhaust to open fully from the factory, including the G8X platform.