[Luke680]

Hello all,

As the title says, I recently installed a new downpipe from Whoosh Motorsports and now I can feel a clunk to the right of the accelerator pedal whenever I go over a bump. The noise occurs between 10-45 mph. Today, I went under the car and completely loosened and re-tightened everything that I touched when I installed the pipe, and did the same to the motor mount. I also tested the control arms, tie rods, sway bar + end links, and CV shafts for any play/movement and found none. While I was under the car, I noticed small cracks beginning to form on the factory downpipe hangar. I suspect that this might be the root cause of the noise. If anyone has experienced this same issue, any advice/fixes would be much appreciated!

Mod List/General Info:
59000 Miles
Sound Symposer Delete
CP-e stage one RMM
Whoosh Motorsports Catted Downpipe
AWE Track Catback
König Tandem Wheels
ESP Intercooler

 

[rob99rt]

When you say "factory downpipe hanger" are you referring to the "brillo pad" mount, or the one near the rear of it for the legs of the downpipe to go through? Got any pics of the cracks you're talking about?

 

[Luke680]

When you say "factory downpipe hanger" are you referring to the "brillo pad" mount, or the one near the rear of it for the legs of the downpipe to go through? Got any pics of the cracks you're talking about?

I am talking about the one for the legs of the downpipe to go through. I did not think to take any photos of the part, but the cracks were beginning to appear and shoot away from the holes where the legs go through. The Whoosh downpipe can not be mounted using the steel wool/brillo pad looking mount.

 

[Foenetik]

I can't speak to your situation exactly but with my COBB DP (no brillo mount), mine was hitting the brace that goes across the sub frame (around where the legs are). I had to make some spacers to lower the brace a bit.

 

[Luke680]

I can't speak to your situation exactly but with my COBB DP (no brillo mount), mine was hitting the brace that goes across the sub frame (around where the legs are). I had to make some spacers to lower the brace a bit.

Thanks for the response, this could be it. What did you use to make the spacers for the cross-brace?

 

[ddfred]

I am talking about the one for the legs of the downpipe to go through. I did not think to take any photos of the part, but the cracks were beginning to appear and shoot away from the holes where the legs go through. The Whoosh downpipe can not be mounted using the steel wool/brillo pad looking mount.

Sometimes the "legs" protrude too far through the lower mount and can hit the chassis; in that case they need to be shortened a bit.

 

[Foenetik]

Thanks for the response, this could be it. What did you use to make the spacers for the cross-brace?

Depends on how much you want to respect me in the future. At first I used a few stacked washers to see if that was the issue. It was, so I left it for 4 months because I was lazy and then I realized it was not the best option so I had some machined. I think they are 1/4".

@ddfred also brings up a good point as that does happen. Mine didn't have that issue as the bracket was adjustable so we made sure it didn't hit.

 

[Luke680]

Depends on how much you want to respect me in the future. At first I used a few stacked washers to see if that was the issue. It was, so I left it for 4 months because I was lazy and then I realized it was not the best option so I had some machined. I think they are 1/4".

@ddfred also brings up a good point as that does happen. Mine didn't have that issue as the bracket was adjustable so we made sure it didn't hit.

Sometimes you just gotta use washers lol. I know Home Depot and other hardware stores sell metal spacers as well, so I will definitely look into this.

 

[Luke680]

Sometimes the "legs" protrude too far through the lower mount and can hit the chassis; in that case they need to be shortened a bit.

I noticed that they are quite close to the chassis, so this could also be it. I will add this to the rapidly growing list of suggestions! Thanks!

 

[rob99rt]

I noticed that they are quite close to the chassis, so this could also be it. I will add this to the rapidly growing list of suggestions! Thanks!

I had to trim mine, too, but be aware that trying to trim those pieces of super hard unearthly metal with a sawzall blade will just infuriate you and make butter knives out of your expensive blades. Get a cut off wheel instead and make really quick work of them.

Don't be me in this instance.... Learn from my poor choice of tooling (when I started) and use what I finished with... You can rip through those things with a cut off wheel in seconds.

 

[junits15]

If you can adjust it that is the cheapest option. However that stock DP hanger is soft and us usually breaks. Because there isn’t enough flex on 99% of aftermarket DPs

here’s another fix:

whoosh motorsports uprated downpipe Hanger Focus ST/RS *FREE SHIPPING*

IN STOCK ! as of 3/28/2023 Replace the weak and worn stamped steel factory Ford bracket with the new whoosh motorsports billet bracket upgrade Features include: Machined from aircraft grade billet aluminum 1 piece press fit red poly bushings Hard anodized Black and Gunmetal finishes...

whoosh-motorsports.myshopify.com

 

[rob99rt]

That's almost as cheap the VW downpipe mount I'm running, but without the need to drill a new hole in the bracket.

 

[Luke680]

If you can adjust it that is the cheapest option. However that stock DP hanger is soft and us usually breaks. Because there isn’t enough flex on 99% of aftermarket DPs

here’s another fix:

whoosh motorsports uprated downpipe Hanger Focus ST/RS *FREE SHIPPING*

IN STOCK ! as of 3/28/2023 Replace the weak and worn stamped steel factory Ford bracket with the new whoosh motorsports billet bracket upgrade Features include: Machined from aircraft grade billet aluminum 1 piece press fit red poly bushings Hard anodized Black and Gunmetal finishes...

whoosh-motorsports.myshopify.com

Yes, I definitely am going to purchase that mount since the cracks are already forming

 

[Foenetik]

If you can adjust it that is the cheapest option. However that stock DP hanger is soft and us usually breaks. Because there isn’t enough flex on 99% of aftermarket DPs

here’s another fix:

whoosh motorsports uprated downpipe Hanger Focus ST/RS *FREE SHIPPING*

IN STOCK ! as of 3/28/2023 Replace the weak and worn stamped steel factory Ford bracket with the new whoosh motorsports billet bracket upgrade Features include: Machined from aircraft grade billet aluminum 1 piece press fit red poly bushings Hard anodized Black and Gunmetal finishes...

whoosh-motorsports.myshopify.com

This is a genuine curiosity question:

If 99% of the downpipe's don't have an appropriate flex then what good does having the stiffer mounts do? Aren't you going to transfer the force to something that's not able to take the force like the headifold or some part of the turbo? If you stiffen all of the mounts, something in the line must take the brunt of the force, no?

edit: I left my stock DP hangar mount because of this. I have full engine and exhaust mounts so I was worried that the whole thing might be too stiff.

 

[junits15]

This is a genuine curiosity question:

If 99% of the downpipe's don't have an appropriate flex then what good does having the stiffer mounts do? Aren't you going to transfer the force to something that's not able to take the force like the headifold or some part of the turbo? If you stiffen all of the mounts, something in the line must take the brunt of the force, no?

edit: I left my stock DP hangar mount because of this. I have full engine and exhaust mounts so I was worried that the whole thing might be too stiff.

It will flex but it’s stiff, switching to the stiffer mount increases NVH but prevents the eventual failure of the stock mount from leaving you with a rattle one day.

The stiff mount allows the DP to bend at the flex, the stock mount is soft so I find that the stiff flex most aftermarket DPs have just shreds it. The DP doesn’t bend at the flex instead it just pushes the whole exhaust down.

A lot of stress is put on that DP hanger with an aftermarket DP especially if launching you can break the DP pins if you’re really aggressive. There really should be more flex on aftermarket DPs the tiny piece they use causes so many issues

 

[rob99rt]

It will flex but it’s stiff, switching to the stiffer mount increases NVH but prevents the eventual failure of the stock mount from leaving you with a rattle one day.

The stiff mount allows the DP to bend at the flex, the stock mount is soft so I find that the stiff flex most aftermarket DPs have just shreds it. The DP doesn’t bend at the flex instead it just pushes the whole exhaust down.

A lot of stress is put on that DP hanger with an aftermarket DP especially if launching you can break the DP pins if you’re really aggressive. There really should be more flex on aftermarket DPs the tiny piece they use causes so many issues

Fwiw, the cvf downpipe has a very good flexible section on it, so I can't imagine it pushing on the mount very hard.

 

[Foenetik]

It will flex but it’s stiff, switching to the stiffer mount increases NVH but prevents the eventual failure of the stock mount from leaving you with a rattle one day.

The stiff mount allows the DP to bend at the flex, the stock mount is soft so I find that the stiff flex most aftermarket DPs have just shreds it. The DP doesn’t bend at the flex instead it just pushes the whole exhaust down.

A lot of stress is put on that DP hanger with an aftermarket DP especially if launching you can break the DP pins if you’re really aggressive. There really should be more flex on aftermarket DPs the tiny piece they use causes so many issues

Understood. You said 99% of the DP's don't have enough flex. So, if you stiffen up everything as directed then I would imagine that the pressure has to go somewhere. I don't disagree with you but if we are aware that the flex isn't enough in the hardware then we should allow flex in the mounts.

 

[junits15]

Understood. You said 99% of the DP's don't have enough flex. So, if you stiffen up everything as directed then I would imagine that the pressure has to go somewhere. I don't disagree with you but if we are aware that the flex isn't enough in the hardware then we should allow flex in the mounts.

The issue is that the stock mount gives way eventually. Some people do seem to be able to adjust it just right so that it lasts which as you described is the best solution.

Youre right, we should allow movement, but its a tough balancing act, I went for the "make everything stiff" route and broke my DP, before that I left it soft and shredded my mount.

 

[TurboGT]

@Foenetik I've personally had a whoosh pipe in my hands, and while the flex is short, it is plyable.

@Luke680 Since this pipe doesn't use the stock brillo mount, I can guarantee you that it is clocked too low. What you want to do is, loosen the Vband at the turbo, put a floor jack under the 2 bolt flange area where it bolts to your catback, and jack it up an inch or so (you'll see it smashing upward on your stock downpipe mount that you said is cracked). Then go back up front, bang on the top part of the pipe with your hand and make sure it rotates upward on the turbo. Tighten the Vband, and then release the floor jack.

When the downpipe is clocked too low, it draws the legs forward toward the subframe.

 

[Luke680]

@Foenetik I've personally had a whoosh pipe in my hands, and while the flex is short, it is plyable.

@Luke680 Since this pipe doesn't use the stock brillo mount, I can guarantee you that it is clocked too low. What you want to do is, loosen the Vband at the turbo, put a floor jack under the 2 bolt flange area where it bolts to your catback, and jack it up an inch or so (you'll see it smashing upward on your stock downpipe mount that you said is cracked). Then go back up front, bang on the top part of the pipe with your hand and make sure it rotates upward on the turbo. Tighten the Vband, and then release the floor jack.

When the downpipe is clocked too low, it draws the legs forward toward the subframe.

Okay, that will be my first step towards fixing this issue. Thank you very much.