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Maybe there's something with the M7 and A8s... My car is procharged, cammed, tubes etc... In track mode you could CLEARLY hear the car close the valves. While crusing at certain RPMs. There's no mistaking or need for some one to be looking down the damn pipes to verify.
BooSSted,
So, you dispute GM's Service Manual. Kind of a stretch.
I have had my exhaust system set to Track Mode in Sound Management continuously for over five months. The NPP valves do not close, so perhaps mine is the only 2018 Z06 Z07 whose exhaust system operates as the GM service manual states. Oh, and yes, my car is bone-stock.
Montana Bob
Last edited by MontanaBob; 07-15-2018 at 12:09 AM.
Reason: Correction of verbiage
So, you dispute GM's Service Manual. Kind of a stretch.
I have had my exhaust system set to Track Mode in Sound Management continuously for over five months. The NPP valves do not close, so perhaps mine is the only 2018 Z06 Z07 whose exhaust system operates as the GM service manual states. Oh, and yes, my car is bone-stock.
Montana Bob
Nothing stretched here, clear fact.
And from the amount of disparity between Corvette owners and the actual functionality of this mode/NPP it seems to be a rather clouded discussion. And not clearly black and white as a few of you want to point out of the manual.
When the car goes from all out racecar sounding V8, to muffled slightly louder than stock there's no mistaking the switch. I guess you should feel good on having one of working 2018 Z06/Z07. Good thing the owners manual doesn't depict track usage, all those overheating Z's... They're all delusional...
Nothing stretched here, clear fact.
And from the amount of disparity between Corvette owners and the actual functionality of this mode/NPP it seems to be a rather clouded discussion. And not clearly black and white as a few of you want to point out of the manual.
When the car goes from all out racecar sounding V8, to muffled slightly louder than stock there's no mistaking the switch. I guess you should feel good on having one of working 2018 Z06/Z07. Good thing the owners manual doesn't depict track usage, all those overheating Z's... They're all delusional...
BooSSted,
So, if I understand your post correctly, you are saying that I am delusional. For that to be true, you would have to be more familiar with my car than am I. Doesn't make sense, does it?
I had a '68 Corvette, (purchased new), originally equipped with an L71/L89 427. Within a year, I converted it to an L88, replete with the competition headers, 4 primaries (per side) into 1 secondary (again, per side), with removable (slide-out) mufflers. The secondaries exited behind the doors. With or without the mufflers inserted, the car was extremely loud at full chat, yet was relatively quiet when feathering the throttle at low RPM. Obviously there were no NPP valves in those days. Perhaps you are experiencing a quiet exhaust when at low RPM, with little throttle input, rather than a perceived closing of the NPP valves.
So, if I understand your post correctly, you are saying that I am delusional. For that to be true, you would have to be more familiar with my car than am I. Doesn't make sense, does it?
I had a '68 Corvette, (purchased new), originally equipped with an L71/L89 427. Within a year, I converted it to an L88, replete with the competition headers, 4 primaries (per side) into 1 secondary (again, per side), with removable (slide-out) mufflers. The secondaries exited behind the doors. With or without the mufflers inserted, the car was extremely loud at full chat, yet was relatively quiet when feathering the throttle at low RPM. Obviously there were no NPP valves in those days. Perhaps you are experiencing a quiet exhaust when at low RPM, with little throttle input, rather than a perceived closing of the NPP valves.
Montana Bob
That's not the case my man... This was crusing at normal RPMs. The car would clearly drop in tone as stated with the mods there is no mistaking the tone of the car. Then even when accelerating there was a however so slight delay for the car to regain its normal 'loud' tone.
I don’t do track mode too much because of the ride. It makes sense that the valves should just be wide open in track. My theory is I had both valve actuators fail. When the valves were closed in tour mode the valves made a hideous clicking noise. When the valves were open, no noise. So when I drove around in the different modes I could tell when they were in the closed position. In sport coasting off throttle the valves were closing because the noise was there. I didn’t try track.
Setting the exhaust in Track Mode doesn't do anything to the ride. You go to the settings icon on the center display, select driving modes and then select engine sound management, followed by Track Mode. That only affects engine sound. Ride is selected through the dial on the console.
Nothing stretched here, clear fact.
And from the amount of disparity between Corvette owners and the actual functionality of this mode/NPP it seems to be a rather clouded discussion. And not clearly black and white as a few of you want to point out of the manual.
When the car goes from all out racecar sounding V8, to muffled slightly louder than stock there's no mistaking the switch. I guess you should feel good on having one of working 2018 Z06/Z07. Good thing the owners manual doesn't depict track usage, all those overheating Z's... They're all delusional...
Mine gets quiet every time it switches to V4 mode. You may have V4 operation switched off using a range controller or by having a tune but that doesn't mean the complete control sequence is defeated. The control sequence for the sound management may continue to work even though the engine itself doesn't switch to V4 mode. I wonder if you put your dash display into info mode and selected the readout that shows whether the engine is in V4 or V8 mode you might actually see V4 when it gets quiet.
That's not the case my man... This was crusing at normal RPMs. The car would clearly drop in tone as stated with the mods there is no mistaking the tone of the car. Then even when accelerating there was a however so slight delay for the car to regain its normal 'loud' tone.
Cruising for me is at low rpms. My car runs along at 50 to 60 mph with the engine turning somewhere between 1000 and 1500 rpm. Even at 75 mph the rpms are lower than 2K. I can hear the exhaust get quiet every time there is a level stretch of road and the cruise control backs off the throttle and the engine switches to V4 operation and once the road hits a little bit of an incline the engine switches back to V8 mode and the exhaust gets loud. I can tell by the sound of the exhaust what mode the engine is in. Loud V8, Quiet V4. Since I have an M7 I only get the quiet/loud operation when the center drive mode dial is set on ECO. In Tour it is Loud all the time.
Bill, I know how to work the car. I cannot comment on the working of the valves in track mode because I do not enjoy the ride quality of that setting. However, in sport mode the valves do open and close at some rate. I thought my writing was pretty clear. Thanks.
Bill, I know how to work the car. I cannot comment on the working of the valves in track mode because I do not enjoy the ride quality of that setting. However, in sport mode the valves do open and close at some rate. I thought my writing was pretty clear. Thanks.
But you can set the exhaust to Track even though you are in Sport driving mode like Bill said.....in case you missed the subtle detail.
Bill, I know how to work the car. I cannot comment on the working of the valves in track mode because I do not enjoy the ride quality of that setting. However, in sport mode the valves do open and close at some rate. I thought my writing was pretty clear. Thanks.
Hate to say it but you really don't know how to work this part of the car. Like I said in post 25, setting the EXHAUST to track mode doesn't do anything to the ride. Use your finger to select settings on the center display (the one that has a storage compartment behind it). Once you get to settings select Drive Mode and then select Exhaust Management. Once you do that you will see several settings including STEALTH and TRACK. Go with TRACK and you will have a loud exhaust when riding in Tour.
This is from the 2017 Owner's Manual and the 15 and 16 ones say the same thing. Haven't checked the 18 and 19 manuals but I doubt they have changed.
Bill
Last edited by Bill Dearborn; 07-15-2018 at 09:23 PM.
Hate to say it but you really don't know how to work this part of the car. Like I said in post 25, setting the EXHAUST to track mode doesn't do anything to the ride. Use your finger to select settings on the center display (the one that has a storage compartment behind it). Once you get to settings select Drive Mode and then select Exhaust Management. Once you do that you will see several settings including STEALTH and TRACK. Go with TRACK and you will have a loud exhaust when riding in Tour.
This is from the 2017 Owner's Manual and the 15 and 16 ones say the same thing. Haven't checked the 18 and 19 manuals but I doubt they have changed.
Bill
Bill,
Verbiage is identical in 2018 Owners Manual although it appears on page 125.
Hello corvette c7 fans and thanks for all your input to my npp fuse question, I did a cold start with the #87 fuse still plugged in before I started my 19 zo6 on a cold start I looked and the outer tailpipe flaps were closed after it warmed up for a min the flaps closed oh and I keep my zo6 in sport mode with the settings set to track in driving mode. any way as I drove and got to my work place with the car running in park because it's an 8 speed auto, I looked and the flaps were closed. after I pulled the #87 fuse I ran the same test and guess what the flaps stayed open all the time cold or hot and while driving at low speeds it sounds so much of a better exhaust note, even under partial throttle the exhaust sounds great and the shift pop is more noticeable. Even when I programmed my zo6 through the settings from the center screen the flaps still functioned as gm makes them work with the #87 fuse in but as I said after I pulled th #87 fuse these flaps stay open all the time in any mode. I enjoy the sound better as I know some people may not enjoy the corvette any way you like , right!!!
Cruising for me is at low rpms. My car runs along at 50 to 60 mph with the engine turning somewhere between 1000 and 1500 rpm. Even at 75 mph the rpms are lower than 2K. I can hear the exhaust get quiet every time there is a level stretch of road and the cruise control backs off the throttle and the engine switches to V4 operation and once the road hits a little bit of an incline the engine switches back to V8 mode and the exhaust gets loud. I can tell by the sound of the exhaust what mode the engine is in. Loud V8, Quiet V4. Since I have an M7 I only get the quiet/loud operation when the center drive mode dial is set on ECO. In Tour it is Loud all the time.
Bill
Bill--debate on fuse #42 seems endless. My understanding based on numerous threads is that while the flaps in Track Mode are considered open, they are still not open 100% of the time--and this can only be accomplished by pulling fuse #42. Is that correct?
Bill--debate on fuse #42 seems endless. My understanding based on numerous threads is that while the flaps in Track Mode are considered open, they are still not open 100% of the time--and this can only be accomplished by pulling fuse #42. Is that correct?
NO!!!! They are open all the time when in track mode. They have two positions open and closed. They will close when the engine is running in V4 mode but that doesn't happen on an M7 unless the car is running in Eco Mode and it doesn't happen on an A8 if the car is actually in Sport or Track Driving Modes. With an A8 in Tour they will be open unless the engine switches to V4 mode or the system thinks it switched even though something prevented it from switching. I am not sure how the Range Module works to prevent the engine from switching to V4 mode but that is done through the ECM while the exhaust control is done by the Chassis Control Module.
Since I have never seen a video showing those valves closing while driving with the exhaust set in Track Mode and the Driving Mode set in Tour on an M7 or an A8 with the exhaust set in Track Mode and the Driving Mode set in Sport I suspect the people making the claim really don't know. My ears and the ears of people riding with me know it doesn't close on my car and all of my fuses are in place. The C7 NPP system doesn't work like the C6 NPP system.
Hello corvette c7 fans and thanks for all your input to my npp fuse question, I did a cold start with the #87 fuse still plugged in before I started my 19 zo6 on a cold start I looked and the outer tailpipe flaps were closed after it warmed up for a min the flaps closed oh and I keep my zo6 in sport mode with the settings set to track in driving mode. any way as I drove and got to my work place with the car running in park because it's an 8 speed auto, I looked and the flaps were closed. after I pulled the #87 fuse I ran the same test and guess what the flaps stayed open all the time cold or hot and while driving at low speeds it sounds so much of a better exhaust note, even under partial throttle the exhaust sounds great and the shift pop is more noticeable. Even when I programmed my zo6 through the settings from the center screen the flaps still functioned as gm makes them work with the #87 fuse in but as I said after I pulled th #87 fuse these flaps stay open all the time in any mode. I enjoy the sound better as I know some people may not enjoy the corvette any way you like , right!!!
First, try putting the exhaust in Track Mode Vs Sport Mode and then select the driving mode as Tour. You will see the exhaust valves stay open while the engine is idling. Track Mode leaves the valves open all the time even when idling.
Exhaust set in Track Mode valves open while idling:
Just to let you know, the valves do close sometimes in Sport and Track when the throttle is closed. I do not know the reason, maybe to keep back pressure? Thanks.
NO!!!! They are open all the time when in track mode. They have two positions open and closed. They will close when the engine is running in V4 mode but that doesn't happen on an M7 unless the car is running in Eco Mode and it doesn't happen on an A8 if the car is actually in Sport or Track Driving Modes. With an A8 in Tour they will be open unless the engine switches to V4 mode or the system thinks it switched even though something prevented it from switching. I am not sure how the Range Module works to prevent the engine from switching to V4 mode but that is done through the ECM while the exhaust control is done by the Chassis Control Module.
Since I have never seen a video showing those valves closing while driving with the exhaust set in Track Mode and the Driving Mode set in Tour on an M7 or an A8 with the exhaust set in Track Mode and the Driving Mode set in Sport I suspect the people making the claim really don't know. My ears and the ears of people riding with me know it doesn't close on my car and all of my fuses are in place. The C7 NPP system doesn't work like the C6 NPP system.
Bill
Bill,
My 2018 Z06 A8 will switch into V4 mode even if I've got the dial set to Sport. I've watched it do this quite a number of times. Won't get into the exhaust valve discussion as I think pictures (while driving) or some type of tattle tale on the actuator valves will be the only sure way to settle this discussion.
07-15-2018, 12:06 AM
