Weird Noise From Side Pipes....Search Performed...Additional Questions

[ASO544]

Notice my pipes has a weird noise from pipes when idling or when I let off after accelerating. Not really a heavy metallic rattle but a kinda odd loose metal vibrating sound that does come from inside the pipes. Sounds like cards in the spokes of a tire.

Any ideas or help is always greatly appreciated.


2013 Build
Roush 427R
TKO 600
1300 miles

[Cashburn]

The earlier issues were a completely different style of pipe from a different manufacturer at the time. The sound you are hearing is the current norm. It is the wadding used within the mufflers. You can replace the mufflers entirely if you do not like the sound, but I will warn you that the performance will suffer as these pipes do a great job of cutting noise but not eating power.

Alternatively you can gut them but your ears will suffer. Drilling and tapping screws will do nothing to stabilize the packing of the mufflers.

[ASO544]

Well crap! Being in the car it sounds kinda weird. Hopefully it's not quite as noticible from a spectators side. Thanks for the info though. Guess my pipes got un-needed SS screws

[jeffnolan]

And BDR427 and I can tell you (our cars are close together) that the box of rocks gets worse over time. Over the winter I may take a chop saw to the sidepipes and repack them. It's embarrassing to decelerate and listen ot that rattling.

Originally Posted by Cashburn

The earlier issues were a completely different style of pipe from a different manufacturer at the time. The sound you are hearing is the current norm. It is the wadding used within the mufflers. You can replace the mufflers entirely if you do not like the sound, but I will warn you that the performance will suffer as these pipes do a great job of cutting noise but not eating power.

Alternatively you can gut them but your ears will suffer. Drilling and tapping screws will do nothing to stabilize the packing of the mufflers.

[ASO544]

Definitely an annoying noise. Think id rather lose a little performance and not have my car sound awful we cruising through town.

[cycleguy55]

Originally Posted by jeffnolan

And BDR427 and I can tell you (our cars are close together) that the box of rocks gets worse over time. Over the winter I may take a chop saw to the sidepipes and repack them. It's embarrassing to decelerate and listen ot that rattling.

If you're going to carve up your side pipes you may want to check out this thread: Classic Roadster exhaust dilemma

[jeffnolan]

cutting them open or replacing them outright are the only two options because the rattling is unacceptable.

[427BDR]

Originally Posted by jeffnolan

cutting them open or replacing them outright are the only two options because the rattling is unacceptable.

Amen Jeff. The rattle has significantly worsened over the 1 yr I've had the car.

Jay, my first backdraft from 2011/2012 didn't have this issue. What's the difference in the pipes and what's the best fix in your opinion? At this point I literally drop it into neutral at 30-40 mph when coming to a stop because if I leave it in gear the rattle is gawd awful embarrassing. People look over like "hey that's a cool car but why does it sound like ****?" LOL!

[Cashburn]

Originally Posted by 427BDR

Amen Jeff. The rattle has significantly worsened over the 1 yr I've had the car.

Jay, my first backdraft from 2011/2012 didn't have this issue. What's the difference in the pipes and what's the best fix in your opinion? At this point I literally drop it into neutral at 30-40 mph when coming to a stop because if I leave it in gear the rattle is gawd awful embarrassing. People look over like "hey that's a cool car but why does it sound like ****?" LOL!

Your first car came from us and did not have a Smeding engine... But I don't know if the noise you are describing is in fact what I am stating is the norm. Unless you guys are both unique at the same time? It's not something our customers are complaining about. So perhaps you need to YouTube it and/or get your dealer to work on it with you?

The current pipes are produced by the same company building far more units for several other BIG kit car companies and again not seeing these complaints on their forums or here.

[ASO544]

My best description is the sound of cards in the spokes of a bicycle. It has it slightly while ideling but really bad when de-accelerating with clutch out. Really odd noise. I already used stainless scres to secure the baffles thinking that was it. I also check all mounting bolts and heat shield bolts. Whatever the noise is is coming from inside the exhaust.

[427BDR]

Originally Posted by Cashburn

Your first car came from us and did not have a Smeding engine... But I don't know if the noise you are describing is in fact what I am stating is the norm. Unless you guys are both unique at the same time? It's not something our customers are complaining about. So perhaps you need to YouTube it and/or get your dealer to work on it with you?

The current pipes are produced by the same company building far more units for several other BIG kit car companies and again not seeing these complaints on their forums or here.

Thanks Jay. Given what you've shared it seems Jeff and I may have received a bad batch. I've put a camera scope down the pipe and I don't see any packing, just perforated baffles along the inner walls of the pipe.

Originally Posted by ASO544

My best description is the sound of cards in the spokes of a bicycle. It has it slightly while ideling but really bad when de-accelerating with clutch out. Really odd noise. I already used stainless scres to secure the baffles thinking that was it. I also check all mounting bolts and heat shield bolts. Whatever the noise is is coming from inside the exhaust.

ASO544, what you are describing is the same issue Jeff and I have on our backdrafts. I also have the "sound of cards" you describe at idle, but it becomes very loud and turns into a rattle during deceleration. We're working with our dealer and backdraft for a solution but I'll secure an alternative set of pipes to fix it before next spring if needed.

Good Luck

[ASO544]

Keep me posted on your progress. At some point this needs to be fixed. BDRs are too nice a car to have this type of embarrassing sound!!! I was hoping BDR would try and help in some way but if not I'll pay to fix it.

[Ozzie Goat]

House of cards ? I'd take that over insane backpressure.

I too, will buy a new set of pipes as soon as the backorder is lifted. Backdraft said it will be a couple weeks.

Group buy and beat them up for a discount ??

Roy

[427BDR]

Originally Posted by Ozzie Goat

House of cards ? I'd take that over insane backpressure.

I too, will buy a new set of pipes as soon as the backorder is lifted. Backdraft said it will be a couple weeks.

Group buy and beat them up for a discount ??

Roy

Hi Roy

Looks like you have the older pipes I think, yes? Our pipes look very different on the inside. They are definitely less restrictive than yours but they waddle, rattle and sound down right like **** on deceleration IMO.

This may all have to do with the level of power the engine produces. Seems like backdraft is doing a lot of coyote installs and they claim few complaints. maybe smaller engines with ~400hp don't shake these pipes as much as larger displacement engines with 550-600hp.

Before you order the new pipes from backdraft let's make sure we pinpoint the source of the issues. Otherwise you may end up disappointed with the pipes.

[Ozzie Goat]

Thanks 427 - I do agree.
Yes, my build #576 is sporting the older pipes, but they have to go.

I looked at ripping them apart and rebuilding, but I can't get the same stainless finish with Frankenstein welds.

One thing I have in my favor is that I have a puny 302 w/340HP-gross.

Yes, I'll stay tuned. Those new pipes are $1,650, I'll want to know they are good to go.

[Cashburn]

Originally Posted by 427BDR

Hi Roy

Looks like you have the older pipes I think, yes? Our pipes look very different on the inside. They are definitely less restrictive than yours but they waddle, rattle and sound down right like **** on deceleration IMO.

This may all have to do with the level of power the engine produces. Seems like backdraft is doing a lot of coyote installs and they claim few complaints. maybe smaller engines with ~400hp don't shake these pipes as much as larger displacement engines with 550-600hp.

Before you order the new pipes from backdraft let's make sure we pinpoint the source of the issues. Otherwise you may end up disappointed with the pipes.

You should put your car on a chassis dyno and see. Those Smeding motors, just saying... Our smaller engine Coyote car just did 715rwhp

The sound you are not used to is the sound of a glasspack muffler. Yes, these are glasspacks... and they save upwards of 50hp (if you are actually making 600hp, it's all relative).

[427BDR]

Originally Posted by Cashburn

You should put your car on a chassis dyno and see. Those Smeding motors, just saying... Our smaller engine Coyote car just did 715rwhp

The sound you are not used to is the sound of a glasspack muffler. Yes, these are glasspacks... and they save upwards of 50hp (if you are actually making 600hp, it's all relative).

Jay can you elaborate? That's the second time you mentioned the smeding engine implying it may be the source of the issue. My engine was dyno'd and made ~581hp. I'm just trying to find a fix for these awful sounding backdraft pipes, so any experience you can share is much appreciated. If your 700 hp coyote doesn't cause the pipes to rattle then Maybe we have busted baffles?

Alistair is also exploring potential fixes so all input is appreciated. Thanks in advance

[Mark Brye]

I had a sound similar to what you guys are talking about. I pulled the side pipe off and put it on my bench and started taping on it to see if I could make the sound. What mine turned out to be was a rock that made its way in between the four primary pipes and made its way down to the collector on the outside of the exhaust. It made a horrid racket. Turned the pipe on edge and the rock rolled out.

[RedEye]

I had some success by filling the space between my outer pipe and inner baffle with high temp silicone. (red stuff). Silicone has traditionally been a good material for vibration reduction.

I used probably 8-10oz of the material, in 4 different injection holes, and let it dry for a few days. Turned out I should have let it dry for probably a week or two. It's been mildly effective to reduce vibration noise, and is my cheap last ditch effort to having new pipes made. Might be worth a try.

[cbreez]

Wow, that's a new one. High HP causes muffler problems??? Funny stuff.

I have watched and seen 800 plus HP small blocks run as smooth as a sewing machine. I am not sure the muffler knows how much power an engine makes.