Anyone have a 3" DP to stock CBE? Need help tracking down exhaust noise.

[paintpollz]

Trying to find other humans with my setup. I have a divorced perrin DP thats mated to the stock CBE. I have exhaust drone, and I'm trying to pin it down, before I start ripping apart the entire exhaust system.

 

Its like unecessary drone between 2500 and 3800 rpm. Anything above that or below it, it sounds normal. It sounds like its coming from the drivers side of the car, but that might just be because I'm sitting on that side. I'm pretty sure its a different noise then the growl that the Dp makes at WOT, as the noises together are different sounding. Gotta figure out a way to track it down. Its tough because I never noticed it when I swapped in the perrin Dp, but that could just be because I wasn't paying attention.

 

stock headers, stock up, catted divorced perrin DP to stock CBE. If you guys could give me places to start, that would be great. I originally thought it could be a rotten gasket somewhere, but Lardo had that happen and said the noise was terrible all around. This is just bad between 2500-3800 rpms.

[spec.B Dream]

No issues at all with mine. I've ran both an ERZ bellmouth catless, CNT bellmouth catted, and currently Invidia divorced catless. I've had some leaks from time to time but replaced all gaskets and tightened up everything and was good to go. You sure it isn't a leak?

[robitrice]

i have a catless perrin DP and have zero drone i can hardly hear my car honestly. sometimes it is just the mind trick playing games on you. Inspect your resonator in the stock mid pipe for any holes or damage as well as the mufflers. I find it interesting you have a drone with the stock catback cause like i said i have the same setup and its hardly audible imo. Did you get a new donut gasket for the DP > CBE with a 3" adapter?

[paintpollz]

i have a catless perrin DP and have zero drone i can hardly hear my car honestly. sometimes it is just the mind trick playing games on you. Inspect your resonator in the stock mid pipe for any holes or damage as well as the mufflers. I find it interesting you have a drone with the stock catback cause like i said i have the same setup and its hardly audible imo. Did you get a new donut gasket for the DP > CBE with a 3" adapter?

 

yep. new gaskets, donut and all. good call on the res

[paintpollz]

if in fact the sound was unique to the drivers side of the car, what could that possibly be?

[robitrice]

exhaust manifold? most of the exhaust is on the passenger side until the the dp meets the cbe where it is in the center.

[paintpollz]

exhaust manifold? most of the exhaust is on the passenger side until the the dp meets the cbe where it is in the center.

 

ya shit thats what i figured.

[paintpollz]

bump.

 

noise is driving me goddman crazy. Can't really hear it 4000rpms or over. Anywhere between 2500 rpms and up, especially when I'm going up a slight incline or under any sort of load, its most noticable.

 

I'm thinking about replacing these gaskets. both UPs, both exhaust manis, and crossovers. I know the turbo to DP is ok, and the DP to MP is fine, because I replaced them all when I put the DP on, and with the stock CBE I used a fresh donut, adapter, and fresh 3" gasket.

 

I'm thinking I could have a rotted gaskets, otherwise, I don't know what else this exhaust noise could be coming from.

 

any more ideas?

[cypher0117]

do your mufflers rattle if you shake them?

[BarManBean]

Are you positive that you put the adaptor, donut, and 3" gasket in the right order at the DP-to-CBE connection?

 

You should have a normal 2-bolt (3") gasket up next to the DP, then the adaptor with the protrusion facing towards the rear of the car, and the donut gasket with the tapered end towards the rear of the car. Just trying to make sure here.

 

If that's the case, tighten the shit out of that connection just to rule it out for sure before you do everything else. Tighten each bolt a little bit at a time.

[paintpollz]

Are you positive that you put the adaptor, donut, and 3" gasket in the right order at the DP-to-CBE connection?

 

You should have a normal 2-bolt (3") gasket up next to the DP, then the adaptor with the protrusion facing towards the rear of the car, and the donut gasket with the tapered end towards the rear of the car. Just trying to make sure here.

 

If that's the case, tighten the shit out of that connection just to rule it out for sure before you do everything else. Tighten each bolt a little bit at a time.

 

I don't think you can mess that up, but, I did install it in the correct way that you are mentioning. I torqued it pretty hard, hard enough where the stock cbe flang is bending all the way into the adapter

[Max Capacity]

Take the mufflers off and drive the car. See if the sounds still there.

 

Sorry I just found this thread, you should have emailed me. My wagon is catless, stock exhaust from the DP back, with 2 washers between the Y pipe flange and the mufflers.

 

No drone.

 

Some have said the exhaust tips may be to short also, they may need to be further past the bumper.

 

My Spec has stock exhuast less mufflers, no drone. The tips on the muffler deletes extend a bit further then stock.

[paintpollz]

Take the mufflers off and drive the car. See if the sounds still there.

 

Sorry I just found this thread, you should have emailed me. My wagon is catless, stock exhaust from the DP back, with 2 washers between the Y pipe flange and the mufflers.

 

No drone.

 

Some have said the exhaust tips may be to short also, they may need to be further past the bumper.

 

My Spec has stock exhuast less mufflers, no drone. The tips on the muffler deletes extend a bit further then stock.

 

I would have emailed. It doesn't sound like its coming from the back of the car though. its more towards the engine. I guess the best way to figure out what's going on is to get it on a lift and see if air is coming out of any part of the exhaust

[BarManBean]

I don't think you can mess that up, but, I did install it in the correct way that you are mentioning. I torqued it pretty hard, hard enough where the stock cbe flang is bending all the way into the adapter

 

That sounds more like you tightened it WAY beyond where it should be. I would imagine you at least have a bit of a leak there. Mine bends a very slight bit matching up to the Cobb DP, but nothing like you are saying if yours is in fact touching the adapter

[paintpollz]

I mean its not flat against, but it bends towards it for sure.

 

I gotta get the thing on a lift and feel for air sneaking out while its running

[Max Capacity]

I mean its not flat against, but it bends towards it for sure.

 

I gotta get the thing on a lift and feel for air sneaking out while its running

 

What, no jack stands ? If you have a leak at that joint you should be able to hear it. If you can't hear it in the driveway, take the car next to a wall.

[paintpollz]

What, no jack stands ? If you have a leak at that joint you should be able to hear it. If you can't hear it in the driveway, take the car next to a wall.

 

I have stands. But a really shitty jack. It doesn't jack high enough

[Max Capacity]

Watch the Sears adds for the $99.00 3 ton black steel jack and two jackstands or the Harbor Fright adds for the $129. Al race jacks that lift to around 18".

 

That Sears steel jack is the first real jack I bought back 10 years ago. It's heavy but a great jack.

[laff79]

It's most likely the DP/catback connection. Mine is leaking and it drives me nuts.

 

If your jack doesn't jack high enough, have you tried a few pieces of plywood under it?

[paintpollz]

It's most likely the DP/catback connection. Mine is leaking and it drives me nuts.

 

If your jack doesn't jack high enough, have you tried a few pieces of plywood under it?

 

It jacks high enough, but it would be a lot easier if it went 6 inches higher

[Max Capacity]

Just looked at the mail, Harbor Fright just sent out the new monthly mailing.

 

Lots of nice jacks, just depends on what your looking for.

 

You are on the mailing list ...right? LOL

 

You should have a selection of 2x4's and may be a couple of 2x6's if the car is low.

 

You'll have all this one day.

[paintpollz]

going to get the car on the jack stands tonight to check this out. should I just put my hands around the exhaust connections and feel if any hot air is coming out?

 

any suggestions while I'm underneath?

[paintpollz]

hmmm.

 

mine doesn't have this flared fitting.

 

 

wondering if this could cause exhaust flow interruption that would creat this noise, especially under load

[BarManBean]

The adapter I had didn't have the flared piece either.

[paintpollz]

All turbo back connections have no leaks. Very difficult to feel for free air around the up pipe and headers.