Straight Pipes from Turbos Back

[froop]

Hello,

Just wondering whether anyone has actually tried this setup or something similar.

I have the worst lucky, but my CP-E axleback has decided to come apart internally so I'm getting a really bad rattle and my exhaust shop told me it cannot be repaired, only replaced. I have AR catless DPs and the CP-E straight through mids without resonators at the moment.

My options are either to get a new muffler cut in for $400 (but I'll have no idea what it'll sound like), buy a new axleback (expensive as I'm in Australia), or do what I'm considering, which is just to remove the faulty muffler and replace it with straight piping for $250. I'll still have the "silencer pipe" so it'll look like an AA Gen 1 signature exhaust.

If it sounds really bad or waaaay too loud I guess I can always get some resonators put into the mids but just wanted some feedback from people who may have done this before.

Cheers,

Alex

[suspenceful]

[froop]

Thanks for that. I did see that second video at least however on the video description for both it seems as though he is running N55 mids which have a resonator.

Looking for a personal review of someone who has run a full straight pipe with no resonators or cats and a straight axleback such as an AA, AFE, or Berk Race.

I know it's going to be loud. Just wondering how much drone there will be haha.

[suspenceful]

Originally Posted by froop

Thanks for that. I did see that second video at least however on the video description for both it seems as though he is running N55 mids which have a resonator.

Looking for a personal review of someone who has run a full straight pipe with no resonators or cats and a straight axleback such as an AA, AFE, or Berk Race.

I know it's going to be loud. Just wondering how much drone there will be haha.

Ahh, I thought those videos were completely straight-piped.

I have 3" catless downpipes and 3" exhaust after that with only one small muffler in back. It drones pretty bad at certain RPMs, but isn't too loud otherwise. I'd expect it to be loud with a drone!

It'd be a mean, throaty loud. Not a tin-can, ricey loud.

[froop]

Originally Posted by suspenceful

Ahh, I thought those videos were completely straight-piped.

I have 3" catless downpipes and 3" exhaust after that with only one small muffler in back. It drones pretty bad at certain RPMs, but isn't too loud otherwise. I'd expect it to be loud with a drone!

It'd be a mean, throaty loud. Not a tin-can, ricey loud.

Thanks for the replies. I think mine is like yours currently. 3" DP, 2.5" dual straight midpipes and then the CP-E race muffler with silencer pipe. Drones a fair bit and is quite loud but not racecar loud lol. Should be interesting without a muffler I'm guessing. When/if I get it done I'll be happy to put some videos up =D

[suspenceful]

Originally Posted by froop

Thanks for the replies. I think mine is like yours currently. 3" DP, 2.5" dual straight midpipes and then the CP-E race muffler with silencer pipe. Drones a fair bit and is quite loud but not racecar loud lol. Should be interesting without a muffler I'm guessing. When/if I get it done I'll be happy to put some videos up =D

Hopefully you beat me to it! Mine also has a weird rattle that comes from the rear muffler. Now that I think about it... maybe something is causing this for the both of us? Wastegate rattle resonating further down?

I toyed with the idea of eliminating the muffler. Please do post videos if you do it.

[froop]

Originally Posted by suspenceful

Hopefully you beat me to it! Mine also has a weird rattle that comes from the rear muffler. Now that I think about it... maybe something is causing this for the both of us? Wastegate rattle resonating further down?

I toyed with the idea of eliminating the muffler. Please do post videos if you do it.

Unfortunately mine is not due to wastegate rattle. I just had RB turbos installed to fix that issue as well as the leaking seals. Mine is quite definitely coming from the inside of the muffler itself. I took it to an exhaust shop today and he had a look all around it and there was good clearance. It was when he banged on the bottom of the muffler that you could hear the rattle which is what I replicated as well at home on a ramp. My guess is that that perforated pipe or something has come a bit loose inside the muffler and the vibration from the exhaust with certain resonances causes the rattle.

But yeah, pretty sure a straight pipe will fix that issue. It just might add a few new noises along with it

[135Pats]

Never owned a straight piped n54 but have heard them in car and outside the car. It's just a wall of noise IMO, very tractor-y sounding. Not that our motor sings to begin with, but it really kills anything exotic about the tone.

I say weld it is as a straight pipe, then add a large resonator to the mids to quiet down the drone. That could be really nice. Aggressive but who cares!

[Lmaiuri]

I think each straight piped application will have a different pitch, drone, startup etc. I have 2.5 cat less Dps connected to stock n54 mids to which I cut out the cats and welded in straight pipe, connected to an AFe exhaust. It probably sounds unlike any other n54 setup; but it does have an exotic note to it. WOT in tunnels sounds like a super car ripping through

[froop]

Yeah even though my exhaust currently drones pretty badly I do really like the tone at WOT. It's a shame it lasted less than 30,000kms... I have the worst luck. HPFP lasted only 36,000kms. Turbos lasted only 55,000kms.

[Lmaiuri]

Originally Posted by froop

Yeah even though my exhaust currently drones pretty badly I do really like the tone at WOT. It's a shame it lasted less than 30,000kms... I have the worst luck. HPFP lasted only 36,000kms. Turbos lasted only 55,000kms.

believe me man, I'm in the same boat. Everything but my block has been replaced with updated components. Most of it was sorted out before I owned the car; but I've had to replace an oil filter housing, coolant tank, and turbos; but the turbos and the coolant tank were covered under warranty. I'm only like 550 out of pocket on things that aren't consumables.

[Nugget]

Not quite what you are looking for but I have a downpipe, twin 2.5" midpipes with Magnaflow resonators then a 3" muffler delete. I highly recommend it.
Not too loud at light throttle or cruising, but sounds great when getting on it.

[froop]

Originally Posted by Nugget

Not quite what you are looking for but I have a downpipe, twin 2.5" midpipes with Magnaflow resonators then a 3" muffler delete. I highly recommend it.
Not too loud at light throttle or cruising, but sounds great when getting on it.

Although yours is an N55 and mine's N54, that exhaust setup sounds quote similar to mine. Can I ask which magnaflow resonators were used? The exhaust shop I'm going to tomorrow to get the muffler replaced with straight pipe is a magnaflow dealer so if I need some resonators after I'll grab them from them.

Going to go to the drags with just the complete straight pipe setup first though =P

[Nugget]

Originally Posted by froop

Although yours is an N55 and mine's N54, that exhaust setup sounds quote similar to mine. Can I ask which magnaflow resonators were used? The exhaust shop I'm going to tomorrow to get the muffler replaced with straight pipe is a magnaflow dealer so if I need some resonators after I'll grab them from them.

Going to go to the drags with just the complete straight pipe setup first though =P

Not sure what the model number is as it was done ages ago.
Here's a couple of blurry pics of where they are located and what the muffler delete looks like.