Equal-length exhaust discussion: new S55 sounds

[ntg44]

Update: Top Gear project still in progress, but it's moving along. They're working out how to partition the system for packaging. Still no sound clips unfortunately, but they told me it should hopefully be wrapped up by end of next week.

[calebcross]

Originally Posted by ntg44

Update: Top Gear project still in progress, but it's moving along. They're working out how to partition the system for packaging. Still no sound clips unfortunately, but they told me it should hopefully be wrapped up by end of next week.

I'm really really excited for this. You're going to go down as a legend in the F80 world!

Keep us updated

[ntg44]

Originally Posted by calebcross

I'm really really excited for this. You're going to go down as a legend in the F80 world!

Keep us updated

Will do. Thanks, but I can't stress enough that this was a team effort between me, spool twice, and RMDZidane. Just want to give credit to where it's due.

[calebcross]

Originally Posted by ntg44

Will do. Thanks, but I can't stress enough that this was a team effort between me, spool twice, and RMDZidane. Just want to give credit to where it's due.

Thanks everybody!!!

[Kilabyte]

[Judd]

Been following this thread, and I finally got enough snow out of the driveway to back my car out. Next thing I know I have the car jacked up in my Driveway with 6 foot high snow banks all around. Can't wait to see the final product. One thing I will add is that I like the exhaust valves, I don't always want to be running around with a screaming mad exhaust. Although when that Honda pulls up along side I want him to hear and see me as I pull away.

[ellipsis212]

Originally Posted by ntg44

Update: Top Gear project still in progress, but it's moving along. They're working out how to partition the system for packaging. Still no sound clips unfortunately, but they told me it should hopefully be wrapped up by end of next week.

Assuming a new thread will be started?

This thing is too much already

[ntg44]

Originally Posted by ellipsis212

Assuming a new thread will be started?

This thing is too much already

When appropriate, yes. My intention will be to leave the discussion here and just have the top gear system in its own thread. But these things usually go off topic anyways. We'll see how it goes.

[bmdoubledru]

Following.

[bmagic1771]

Following

[Ed_rx7]

Originally Posted by ntg44

Yep. Just need to delete the x pipe at the beginning of the system in addition to the above changes and you're good to go.

So what would you suggest if modifying a MPE? Would I remove the h pipe just after the secondary cats and then put in another one close to the back box? Or could I have both in there ?

[Lifestyler]

Originally Posted by Ed_rx7

So what would you suggest if modifying a MPE? Would I remove the h pipe just after the secondary cats and then put in another one close to the back box? Or could I have both in there ?

Remove front H pipe and add 14inch to Passenger side the before muffler do the H

[Ed_rx7]

Cheers

[figure99]

Originally Posted by ntg44

Update: Top Gear project still in progress, but it's moving along. They're working out how to partition the system for packaging. Still no sound clips unfortunately, but they told me it should hopefully be wrapped up by end of next week.

Been following since the beginning of the initial thread... can't wait to see the results. Any additional updates this week?

[ntg44]

Originally Posted by figure99

Been following since the beginning of the initial thread... can't wait to see the results. Any additional updates this week?

Not yet. I usually get status updates on Friday evenings. I'll relay them as soon as they're communicated to me. Taking a bit longer than I expected, but this exhaust also isn't the only project being worked on, so I understand. But I'm as friggin' excited/impatient as anyone else

[ntg44]

Top Gear Exhaust Update: Project still in progress, but it’s getting there . But the good news is I should have a sound clip for everyone next week! This is definitely wrapping up soon, and I anticipate many more details to be revealed in the next few weeks.

[GT_Juls]

Originally Posted by ntg44

top gear exhaust update: project still in progress, but it's getting there . But the good news is i should have a sound clip for everyone next week! This is definitely wrapping up soon, and i anticipate many more details to be revealed in the next few weeks.

gahhhhh i cant wait!!! 🤣

[///Mani]

Wow! Crazy to see what progress has been. How's everyone doing? Spool, I don't know if you remember me but I texted about doing the EQ mod plus secondary cat replacement with race mufflers, I haven't gotten the chance to do it as I went to Asia as well like RMDZidane. My plan based off what I've seen is...

OEM Stock Muffler
Resonator/H Pipe removal
14" U bend
H-pipe as close to differential
Straight pipe replacement of secondary cats (I want it loud when valves open, if the tone is unbearable I'll put the magnaflow race mufflers)

I am going to get into contact with exhaust solutions hopefully they are not too busy like they were in December. I am curious have you done any changes to your exhaust, I remember yours being great tonally; how is the loudness compared to stock? Also what do you think of my plan will it be loud and somewhat deep and pleasant tone?

[spool twice]

Originally Posted by ///mpower.nick

Wow! Crazy to see what progress has been. How's everyone doing? Spool, I don't know if you remember me but I texted about doing the EQ mod plus secondary cat replacement with race mufflers, I haven't gotten the chance to do it as I went to Asia as well like RMDZidane. My plan based off what I've seen is...

OEM Stock Muffler
Resonator/H Pipe removal
14" U bend
H-pipe as close to differential
Straight pipe replacement of secondary cats (I want it loud when valves open, if the tone is unbearable I'll put the magnaflow race mufflers)

I am going to get into contact with exhaust solutions hopefully they are not too busy like they were in December. I am curious have you done any changes to your exhaust, I remember yours being great tonally; how is the loudness compared to stock? Also what do you think of my plan will it be loud and somewhat deep and pleasant tone?

Just remember that the U-bend needs to be more than 14", it has to also accomodate for the missing length of a pipe that should have been there, but was replaced bu the U-shape bend. Overall pipe length between the drive and passenger should have a total difference of 14" before they cross over. For instance, where my new pipes start to where the crossover is located, the drivers side pipe length is 36", whereas my passenger side is 50" in total length leading up to the inlet of the crossover.

I swapped my H-pipe for a flowmaster 815953 crossover pipe. It balanced out the sound more during part throttle situations, but it got rid of the "rawness" at open throttle. I wish I could have the best of both worlds, but thus car I'm enjoying the sound completely, especially in the 4,500-5,000rpm range as it sounds:

Overall, best $450 mod I could do to keep a stock-like appearance and having reasonable volume (I would actually say its subjectively quieter due to the more balanced and rounded frequencies that shine through where as the stock system sounded harsh and peaky)

[Ed_rx7]

So who’s gonna measure and tell us how much length is needed in the u bend? I think this will eliminate any confusion.

[ntg44]

Originally Posted by Ed_rx7

So who’s gonna measure and tell us how much length is needed in the u bend? I think this will eliminate any confusion.

You already know how much is needed. 14 inches more, measured from downpipe connection. Everyone is going to cut and place the U bend in a different spot, not to mention deleting the resonator will be a little different from custom job to job. That's why the only correct way to measure is from downpipe connection. There is no one size fits all solution.

[///Mani]

Originally Posted by spool twice

Just remember that the U-bend needs to be more than 14", it has to also accomodate for the missing length of a pipe that should have been there, but was replaced bu the U-shape bend. Overall pipe length between the drive and passenger should have a total difference of 14" before they cross over. For instance, where my new pipes start to where the crossover is located, the drivers side pipe length is 36", whereas my passenger side is 50" in total length leading up to the inlet of the crossover.

I swapped my H-pipe for a flowmaster 815953 crossover pipe. It balanced out the sound more during part throttle situations, but it got rid of the "rawness" at open throttle. I wish I could have the best of both worlds, but thus car I'm enjoying the sound completely, especially in the 4,500-5,000rpm range as it sounds:

Overall, best $450 mod I could do to keep a stock-like appearance and having reasonable volume (I would actually say its subjectively quieter due to the more balanced and rounded frequencies that shine through where as the stock system sounded harsh and peaky)

Ah I think I see what you are saying, so basically measure out the length that originally would be there with stock pipe and add it to the U-bend. So lets say the U-bend will take 6" length in the original pipe to be placed, I just need to accommodate those 6" in the U-bend itself making the length of the U-bend around 20"?

Have you done anything in regards to your secondary cats or your OEM Hpipe/resonator?