Custom 3” Downpipes & Exhaust

[Kruppa]

Car is headed back to same shop for intercooler piping and custom intake. I just made a bunch of Amazon purchases to attempt to take quality video/audio of my setup as the iPhone wasn’t cutting it. I’ll post some content in a few days.

 

[Kruppa]

Ok I did this for you guys. This is my “I have no friends here but need to get quality audio and video clips of my car” Osmo pocket does 4k60 and tracking mode so it will automatically follow my car with iPhone as viewing screen and got tripod with nice add-on mic with shock mount and windshield. Don’t know how good it will be but definitely better audio than iPhone. I’ll try to get some content tomorrow.

 

[Nine29]

Met up with @kpkimmel1983 and got a few quick videos. The area is really busy so there's a lot of road noise...but it's something!

I'll work on quieter area and more clips. And do a proper launch where I don't roll first. And clean the car lol.

Launch

Clip 1

Clip 2

That looks like Mound Road...fun place to get on it if you can avoid the potholes! Nice work on the pipes ...(from a fellow GP'er)

 

[Kruppa]

That looks like Mound Road...fun place to get on it if you can avoid the potholes! Nice work on the pipes ...(from a fellow GP'er)

It is indeed Mound Rd - my Dunkin coffee spot (can’t take MA out of me). GP baby!

 

[Brucecris]

Ok I did this for you guys. This is my “I have no friends here but need to get quality audio and video clips of my car” Osmo pocket does 4k60 and tracking mode so it will automatically follow my car with iPhone as viewing screen and got tripod with nice add-on mic with shock mount and windshield. Don’t know how good it will be but definitely better audio than iPhone. I’ll try to get some content tomorrow.

View attachment 3660

Will somebody be this guys friend already? Thx for sharing!!


Sent from my iPhone using Tapatalk

 

[Kruppa]

Will somebody be this guys friend already? Thx for sharing!!


Sent from my iPhone using Tapatalk

lol I swear I had lots of friends before. I signed onto a new job, sold my house and 3 weeks later COVID hit so we drove 14 hours from MA to MI and with everything shut down and people being safe so hard to meet people.

In other news I spent hours washing both cars since finally the weather said 5 days of no precipitation. I was just loading the stuff to go get some content and look out the windows and it’s snowing so hard. Dammnit!

 

[Nine29]

lol I swear I had lots of friends before. I signed onto a new job, sold my house and 3 weeks later COVID hit so we drove 14 hours from MA to MI and with everything shut down and people being safe so hard to meet people.

In other news I spent hours washing both cars since finally the weather said 5 days of no precipitation. I was just loading the stuff to go get some content and look out the windows and it’s snowing so hard. Dammnit!

Ha! Just washed mine yesterday for it's first bath since buying it 2 weeks ago, and now I don't want to drive it with all the snow (and salt) we just got today!

 

[Kruppa]

Wanted more stealth so sprayed rear section black after adding some more resonators.

 

[Jwbreeding]

Did they ever say if there were going to mass produce the catback like they are with the downpipes?

 

[Kruppa]

Ended up wanting the exhaust more quiet - really wanted to hear mostly intake and turbo sound. We replaced the bottle style vibrant resonators up front with vibrant ultra quiet and put the old bottle ones into the rear between the mid muffler and rear mufflers. It’s perfect for me now.

Startup

 

[Kruppa]

Did they ever say if there were going to mass produce the catback like they are with the downpipes?

He is going to focus more on downpipes and intake but I think he would be open to making that for people. 100% locally not sure about when he would be ready for shipping. I’d just reach out and ask though!

 

[Jwbreeding]

He is going to focus more on downpipes and intake but I think he would be open to making that for people. 100% locally not sure about when he would be ready for shipping. I’d just reach out and ask though!

Sounds good, thanks for the info.

 

[Novagunner]

That does sound really nice. That was a warm start, rt? How loud are cold starts? My neighbors hated my coyote on cold starts and it was a mild(ish) exhaust.

Do you happen to have the parts list for the resonators/mufflers?

 

[Kruppa]

That does sound really nice. That was a warm start, rt? How loud are cold starts? My neighbors hated my coyote on cold starts and it was a mild(ish) exhaust.

Do you happen to have the parts list for the resonators/mufflers?

Correct that was a warm start, I'll try to get a cold start later - maybe 30% louder.

Here is the parts list:

Downpipes: Custom 3" with G-Sport 300 CSPI
Front Resonators: Vibrant Ultraquiet #1142
Custom X Pipe 3"
Mid Muffler: Magnaflow #12599 (x-pipe internal design)
Rear resonators: Vibrant Bottle Style #1794
Rear Mufflers: Vibrant Streetpower Oval Mufflers #1111
Custom dual 2.5" tips

 

[Novagunner]

Awesome! Thanks dude.

 

[SwagSolo]

Jesus looks like 6” pipe!


Sent from my iPad using Tapatalk

 

[F=MA]

I swapped mufflers today....total lateral move. Same tone, volume and drone frequency and the Magnaflows before the 1/4 wave resonators. mine is still 187hz...not sure why yours was so much lower. Minor differences in parts make a big difference I guess.

So anyway please tell me more about the 1/4 wave resonators and what device you used to get the frequency, etc. The natural frequency of the truck seems to max out at 1500 rpm (rattles the vehicle structure) and occurs such as accelerating slowly and slowing down slowly while driving through city streets in normal or sport modes. The loud exhaust drone is on the highway at 2000 rpm when the engine shifts into 9th or 10th gear. The low rpm rattle occurs even if it passes through the 1500 rpm range quickly. The rattle is shorter duration. It is rattling something beneath the console and somewhere in the third seat area. I pulled the inserts out of the spare tire area and tried driving with sunroof panels in all postions but it still vibrates at 1500 rpm. I pulled all loose items out of the vehicle and still rattles so it is vibrating deeper in the structure. I was able to change the tone of the console vibration by pushing my hand against the floor of the forward console opening where the cigarette lighter is. It slowly returned to the previous deeper rattle sound.

 

[Bucephalus]

Are you considering ceramic coatings?

 

[UNBROKEN]

So anyway please tell me more about the 1/4 wave resonators and what device you used to get the frequency, etc. The natural frequency of the truck seems to max out at 1500 rpm (rattles the vehicle structure) and occurs such as accelerating slowly and slowing down slowly while driving through city streets in normal or sport modes. The lous exhaust drone is on the highway at 2000 rpm when the engine shifts into 9th or 10th gear. The low rpm rattle occurs even if it passes through the 1500 rpm range quickly. The rattle is shorter duration. It is rattling something beneath the console and somewhere in the third seat area. I pulled the inserts out of the spare tire area and tried driving with sunroof panels in all postions but it still vibrates at 1500 rpm. I pulled all loose items out of the vehicle and still rattles so it is vibrating deeper in the structure. I was able to change the tone of the console vibration by pushing my hand against the floor of the forward console opening where the cigarette lighter is. It slowly returned to the previous deeper rattle sound.

Rattles are a separate issue than drone but an exhaust system can definitely bring them out if it’s a harmonic vibration...in that case you just have to figure out what it is and either isolate or deaden it.
Drone is easier to fix. Just use a spectrum analyzer app on your phone to find the drone frequency then build the resonators to the length needed. Divide 1100 by the drone frequency...that will give you the wave length. Divide than number by 4 for the 1/4 wave length then multiply that by 12 for the length in inches the resonator needs to be.

 

[F=MA]

Rattles are a separate issue than drone but an exhaust system can definitely bring them out if it’s a harmonic vibration...in that case you just have to figure out what it is and either isolate or deaden it.
Drone is easier to fix. Just use a spectrum analyzer app on your phone to find the drone frequency then build the resonators to the length needed. Divide 1100 by the drone frequency...that will give you the wave length. Divide than number by 4 for the 1/4 wave length then multiply that by 12 for the length in inches the resonator needs to be.

Magnaflow #19515 - I can generate a non-stop vibration throughout the vehicle in park by revving the engine up around 1500 rpm (listen to attched video). When I drive the vehicle I hear this same annoying frequency rattle passing through this rpm range. This has occurred since the system was first installed. When driving it occurs ascending or descending through the rpm range. For a vehicle that has no squeaks or rattles this exhaust related natural frequency is very annoying. An additional drone in higher gears is super loud at 2000 rpm. Any ideas how to kill the 1500 rpm exhaust frequency vibration using exhaust mods versus tearing the interior apart and applying sound deadener?