MPE exhaust valves open sport and sport plus

[TRKY]

Installed MPE exhaust about 2 weeks ago and since day 1when I am I switch to sport and sport plus the valves stay open. Whe idling and rev the engine it's the same as the valve delete mod when in sport and sport plus. Select efficient and the valves close. Anyone else notice this?

[chiplee]

Originally Posted by TRKY

Anyone else notice this?

Yes. Everyone.

[boostaholic786]

Thats the way they were designed... If you put your car in ECO mode your probably not really getting on the throttle (hence ECO MODE) so they designed the exhaust to have one mode that makes the car somewhat more quiet.

[CanAutM3]

This topic has been extensively discussed.

The valve control logic with the MPE is no different than with the stock exhaust. In efficient, the valves are mostly closed; they only open above ~4000RPM. In Sport and Sport+, they are mostly open; only closing at low RPM high gear cruising to avoid drone.

From the Exhaust Deep Dive Interview:

For instance, if you select the COMFORT mode, the exhaust valves are fully closed in the lower revs ranges. If there is a greater load demand at higher engine speeds, they open up. When driving with a constant load in COMFORT mode, the valves generally remain closed to achieve a maximum level of everyday comfort over long distances.

In SPORT and SPORT PLUS modes, other engine characteristics are selected for controlling the exhaust valves. At lower gears, the exhaust valves are always open, while when higher gears are selected under constant driving conditions, they are closed; however, if the load conditions change accordingly, they open up in a flash. There are also ranges in which we have chosen to close the valves, for instance at low engine speeds in high gears. In these ranges, which are frequently selected in the automatic mode of the M DKG Drivelogic for driving at maximum efficiency, the exhaust tract in turbo engines would have a tendency to drone if there were no damping.

[TRKY]

Not sure if its just the sound of the exhaust but after installing the MPE I dont hear the valves closing at all is what I have noticed. Very different to how it was with the OEM exhaust. It seems they are always open if I am cruising, low RPM high gear. I get no difference in sound from the valve delete mod. If the car is idling switching between comfort and sport/plus opens the valves as well.

[CanAutM3]

Originally Posted by TRKY

Not sure if its just the sound of the exhaust but after installing the MPE I dont hear the valves closing at all is what I have noticed. Very different to how it was with the OEM exhaust. It seems they are always open if I am cruising, low RPM high gear. I get no difference in sound from the valve delete mod. If the car is idling switching between comfort and sport/plus opens the valves as well.

Are your exhaust valves properly connected?

Installing the MPE does nothing to alter the software in the car's ECU, hence the logic for the valve control stays the same as with the stock exhaust.

[dmk08]

Originally Posted by CanAutM3

Are your exhaust valves properly connected?

Installing the MPE does nothing to alter the software in the car's ECU, hence the logic for the valve control stays the same as with the stock exhaust.

So if the valves are closed in efficient and the car always starts in efficient why does GOLFFR closing his manually before cold start matter? Is he actually bypassing the cold start process? Sorry just a random question but my car is loud as crap on cold start which should be 'efficient' every time.

[CanAutM3]

Originally Posted by dmk08

So if the valves are closed in efficient and the car always starts in efficient why does GOLFFR closing his manually before cold start matter? Is he actually bypassing the cold start process? Sorry just a random question but my car is loud as crap on cold start which should be 'efficient' every time.

My impression has been that the valves close for the cold start sequence regardless which mode is selected. This impression seems to be confirmed by GOLFRR's video

[Bob (Los Angeles)]

On delivery of a 2016 M3, a couple of days ago, the salesperson demonstrated how apparently to open the exhaust valves on a cold start, on an stock (unmodified) car. His method was to turn on the ignition (start button with foot off of the brake), switch to sport plus, depress the throttle pedal, and then to start the engine by depressing the brake while again pressing the start button.

[Brasko]

Originally Posted by Bob (Los Angeles)

On delivery of a 2016 M3, a couple of days ago, the salesperson demonstrated how apparently to open the exhaust valves on a cold start, on an stock (unmodified) car. His method was to turn on the ignition (start button with foot off of the brake), switch to sport plus, depress the throttle pedal, and then to start the engine by depressing the brake while again pressing the start button.

That's exactly how I've done it in the past. You can really tell a difference between cold starts with the valve open vs. closed with this method. You'll notice that with the S55 cold start up, the exhaust will be loud for approximately 60 seconds before idling down to a nice burble. I've set a stop watch several times to measure this. Happens if I let the car sit a several hours or several days.

I've got a few cold start videos I was going to share that show this, but not certain how to upload videos. I'll post some once I figure it out.

[JoeyBananas]

What's the point of getting the Electroiv Valve controller then?

[Jimbooo]

Originally Posted by JoeyBananas

What's the point of getting the Electroiv Valve controller then?

Although the cold start open valve trick works as soon as you drive off the valves will resume oem operation. With the valve controller you can choose to open them all the time. I have the cg precision controller on my MPE and it's made a huge difference. You don't realise how often the valves are closed in oem setups regardless of sport or sport plus mode. Yes they open when you floor it but the noise from 1000-3000rpm is far better with valves forced open. The only negative to open valves as mentioned is motorway cruising when it drones. With the controller you can return to oem operation at the press of a button.
Another rarely mentioned benefit of open valves is a much more prolific bark or whatever you call it when you lift off the pedal quickly and the pressure dumps. It's really quite loud and puts a big grin on my face every day. Overrun burble is also louder as in both these situations with oem setup the valves would be usually closed.

If you've spent the money needed to fit an MPE I can't thing of any reason at all why anyone wouldn't get a valve controller to make the most of it.

[JoeyBananas]

Originally Posted by Jimbooo

Although the cold start open valve trick works as soon as you drive off the valves will resume oem operation. With the valve controller you can choose to open them all the time. I have the cg precision controller on my MPE and it's made a huge difference. You don't realise how often the valves are closed in oem setups regardless of sport or sport plus mode. Yes they open when you floor it but the noise from 1000-3000rpm is far better with valves forced open. The only negative to open valves as mentioned is motorway cruising when it drones. With the controller you can return to oem operation at the press of a button.
Another rarely mentioned benefit of open valves is a much more prolific bark or whatever you call it when you lift off the pedal quickly and the pressure dumps. It's really quite loud and puts a big grin on my face every day. Overrun burble is also louder as in both these situations with oem setup the valves would be usually closed.

If you've spent the money needed to fit an MPE I can't thing of any reason at all why anyone wouldn't get a valve controller to make the most of it.

Excellent explanation!, thank you!

[JS_M3_F80]

So I was wondering why my MPE doesn't sound as loud as when I start driving the car and also after the car warms up the farts are not loud enough it is pretty much like the stock exhaust so I was thinking maybe do to the valve thing especially when the car builts up turbo with third gear the car used to sound so much louder