Exhaust Valve Function \ Questions

[SixPost]

Recently made the switch to M6 mufflers with the understanding that the vacuum controlled exhaust valves would continue to work after the install, mostly because my car shouldn't know the difference. Valves are not open @ cold starts after the install, and its hard to know if they're open over 3000 RPM because that takes me pressing down the gas pedal.

Took the diffuser apart today and inspected the tubing from each muffler up the control valve in the trunk where you would hook up an exhaustmeister... no issues. Both valves function normally... I can manually open the valve then put a finger over the vacuum inlet, and the valves stay open. The spring pressure required to open the M6 valves feels the same as the stock 650 ones...

Has anyone with a 650 made the switch to M6 mufflers and had the valves continue to work? Any ideas on what may be wrong or things I could look into to help solve this problem?

Thanks

[MSUGOGRN]

I unfortunately have no answer but this is something I have been considering (switch to m6 mufflers) and this was a key concern of mine so I will follow for sure. Hope someone has a solid answer on this.