Somebody recently came up with a board and shared parts list and assembly instruction. Perhaps someone following it can chime in. 15 here so not in my scope of thing to do.
I'm looking for a method to force the muffler butterfly valves closed even while in Sport / Performance / Track mode. I've read the threads on pulling the fuse to force it always open, but that doesn't work to keep them always closed.
I've got longtubes / cam / whipple, and would like the option to keep the sleeper disguise.
No doubt the open side flows better, but I'd never have expected a 20whp difference...how modded are you?My car lost about 20whp on a dyno with the mufflers in Tour mode so it's safe to assume there's a horsepower impact. The difference was mostly above 4k, which probably means the open side flows better!
Not OP but for me, I would like the ability to keep the suspension and steering in performance mode all of the time but still have flexibility to change the exhaust note. I like the valves open most of the time but certain situations like my driveway/neighborhood or cruising in 6th gear on the interstate, I’d like to shut the valves without having to switch the suspension mode. I really cannot stand the feel of the suspension in tour mode… in any driving conditions. Car feels like a land yacht.out of curiosity why do you want to force them closed?
Rotofab, otherwise stock, on a Dynapack. 370whp first pull, 367 second pull, 350 3rd in Tour mode. There probably wasn't enough cooling between pulls, but it still looks like the exhaust or drive mode matters.No doubt the open side flows better, but I'd never have expected a 20whp difference...how modded are you?
My car (2017 6M) has a few mods (ARH longtubes, BTR Stage 3 PD cam, Whipple), so it's really loud with the baffles open. I'd like the option for stiffer suspension and heavier steering all the time, and only sounding hyper aggressive when I want.out of curiosity why do you want to force them closed?
Thank you! I'll go check this out.Found it...!
DIY Bi-Valve controller for early modelsI am documenting this here and on Thingiverse (Chevy NPP/Bi-Valve Exhaust Controller by c4b4the04) for folks to follow. I KNOW THESE ARE AVAILABLE FOR SALE in Australia. If you are a tinkerer and enjoy doing things yourself, this is a fun project and you might have all the pieces lying around...www.ssforums.com
I did not know that would be available in HPTuners settings! I might have to tinker with that so I can keep it quiet while the wife and baby are in the car without the dynamic drawbacks of tour mode.if you are tuned, you can do it thru HP tuners. It is in the FPCM. I currently have mine closed on my track setting. That way I can make nefarious trips to Mexico without drawing undo attention to my jackassery.
Mode 0-3 corresponds to Tour-Sport-Perf-Track. Change the values in which S-P-T to match Tour and you are good to go. You can even play around with the RPM and gear threshold if you want.I did not know that would be available in HPTuners settings! I might have to tinker with that so I can keep it quiet while the wife and baby are in the car without the dynamic drawbacks of tour mode.