CAMARO6 - View Single Post - Flowmaster American Thunder Dual Mode Axle-back (NPP) for 2016+ Camaro SS & ZL1

VegasZ · 12-29-2019, 01:04 PM

A couple question for the Flowmaster guys / gals or anyone that already has one of these on their ZL1.

Does the exhaust valve closing during off throttle bother the sound at all? Can you tell that it's switching between the two muffler types instead of using a single one all the time? From the sound in your videos it doesn't seem to bother it but theres a spot around 3 - 4k RPMs that sounds different than the rest of the RPM range, is this stupid valve the cause or is it something else in the motor that just sounds different in that range?

Thanks so much for any help! I'm getting ready to order an exhaust for it but it's so hard to tell what they really sound like on the internet esp when most people use shit microphones to capture the sound. Your recording is one of the best I have heard not only in how the car sounds but the quality of the capture. Did you use a real Mic to capture it?

I have removed the fuse for the NPP and it def made a difference although its still not loud enough esp when off throttle but you can tell that it's louder than it was with the fuse in so it's deff closing the exhaust valve under a certian throttle amount or whatever they use to base the valve operation off of instead of just relying on the settings we can manipulate to force them to be "open all the time" since they are overriding that setting for cruising throttle for example.

I could keep the fuse out but it seems kinda silly to buy an NPP aftermarket exhaust and pay extra for it if you can't actually use it because of the other BS the car is deciding to do with that valve instead of leaving it alone for us to set as we want.

If you can't tell I hate how quiet the exhaust is inside the car, I have a 6m and have always driven sticks off of the sound of the engine more than looking at gauges and to know if I put the right amount of throttle to take off without having either to much or not enough. If I have music on at even a moderate level the exhaust is basically un audible inside the car with the fuse in unless you give it a good jab of throttle. Removing the fuse made a small difference in the RPM ranges that it was closing on but not enough for me to not need something aftermarket.

I had a 93 mustang GT back in 96 when I was 18 that had flowmasters and I LOVED the way it sounded. I know Camaros and Mustangs sound different but it had that nice old school muscle car sound that I can't come up with a word to describe other than old school muscle car. I assume you have an idea of what im talking about since it was your company that made them. The American thunder seems to sound the closest to the sound im looking for at least when the valve is open. The closer I can get to how the GT sounded inside the happier I will be. I'm totally fine with the tone / sound being different from a GT but that is the level of in car volume I am searching for. You could always hear the exhaust inside of the car even at very low RPM. People today would probably call it drone in the lower RMP range but to me that was the best part of the sound and I ended up driving around in that RPM range more than I should of or short shifting so I could stay in it

Last question, is it even possible to get the exhaust loud enough to make it sound anything like a 80something to 93 Mustang GT inside the car?

Thanks again!

12-29-2019, 01:04 PM	#160
VegasZ Drives: 2020 ZL1 Join Date: Dec 2019 Location: Las Vegas Posts: 60	A couple question for the Flowmaster guys / gals or anyone that already has one of these on their ZL1. Does the exhaust valve closing during off throttle bother the sound at all? Can you tell that it's switching between the two muffler types instead of using a single one all the time? From the sound in your videos it doesn't seem to bother it but theres a spot around 3 - 4k RPMs that sounds different than the rest of the RPM range, is this stupid valve the cause or is it something else in the motor that just sounds different in that range? Thanks so much for any help! I'm getting ready to order an exhaust for it but it's so hard to tell what they really sound like on the internet esp when most people use shit microphones to capture the sound. Your recording is one of the best I have heard not only in how the car sounds but the quality of the capture. Did you use a real Mic to capture it? I have removed the fuse for the NPP and it def made a difference although its still not loud enough esp when off throttle but you can tell that it's louder than it was with the fuse in so it's deff closing the exhaust valve under a certian throttle amount or whatever they use to base the valve operation off of instead of just relying on the settings we can manipulate to force them to be "open all the time" since they are overriding that setting for cruising throttle for example. I could keep the fuse out but it seems kinda silly to buy an NPP aftermarket exhaust and pay extra for it if you can't actually use it because of the other BS the car is deciding to do with that valve instead of leaving it alone for us to set as we want. If you can't tell I hate how quiet the exhaust is inside the car, I have a 6m and have always driven sticks off of the sound of the engine more than looking at gauges and to know if I put the right amount of throttle to take off without having either to much or not enough. If I have music on at even a moderate level the exhaust is basically un audible inside the car with the fuse in unless you give it a good jab of throttle. Removing the fuse made a small difference in the RPM ranges that it was closing on but not enough for me to not need something aftermarket. I had a 93 mustang GT back in 96 when I was 18 that had flowmasters and I LOVED the way it sounded. I know Camaros and Mustangs sound different but it had that nice old school muscle car sound that I can't come up with a word to describe other than old school muscle car. I assume you have an idea of what im talking about since it was your company that made them. The American thunder seems to sound the closest to the sound im looking for at least when the valve is open. The closer I can get to how the GT sounded inside the happier I will be. I'm totally fine with the tone / sound being different from a GT but that is the level of in car volume I am searching for. You could always hear the exhaust inside of the car even at very low RPM. People today would probably call it drone in the lower RMP range but to me that was the best part of the sound and I ended up driving around in that RPM range more than I should of or short shifting so I could stay in it Last question, is it even possible to get the exhaust loud enough to make it sound anything like a 80something to 93 Mustang GT inside the car? Thanks again! Last edited by VegasZ; 12-29-2019 at 01:22 PM.