What's up everyone! I recently had my dp installed and after the install I hear this weird noise coming under from the passenger side and the rear as well. I usually hear the sound when I go over speed bumps. It sounds like the dp is rubbing against something (maybe the cross members) also what it could be is I need some new exhaust hangers. Help me out guys. BTW before the dp install I never heard the noise. I have about 31,000 miles on the my 2005 wrx. TIA.

Here's my mods:
Tein basics coilovers
STI uppipe
helix catted dp
Hks hi power
eibach camber bolts
ic hoses
spt short ram intake
stage 2 ap acn map

 

The Helix DP its hitting the transmission crossmember.

Only way to fix it is, install Group-N engine mounts and tranny mount.

It's a very common problem with the Helix design.

*only other possibilty is when the up-pipe got put in, the turbo got shifted a bit to far and it makes the DP fit even closer to the tranny. But seeing as its a flex design up-pipe as well, most likely its just the crummy Helix design.

FYI- We see this (Helix DP) issue all the time

-Noah

 

Thanks Noah for the quick reply. Will the helix dp hitting the transmission crossmember cause a significant damage to my car if I don't fix this problem?

 

Significant damage? Anytime you have two things knocking together, something is going to break given enough time.

Look at it this way, here's your excuse to buy and install more mods, and those should definitely enhance the way your car feels.

So, here are your choices:
1. do nothing, let something break and pay to fix it
2. buy new mods to fix problem and enjoy car more
3. pay for and install a different dp
3. reinstall factory dp and admit defeat

The correct choice seems pretty obvious to me , remember, you've gotta pay to play, regardless of your hobby...and modding cars is a relatively cheap one.

 

Yeah you're right, I just got the dp installed last week and most likely either put the stock dp back again or trim the crossmember which I really dont feel comfortable in doing.

 

it's too bad really, Helix used to fit, I know I had one. I still traded out for a Titek catless though.

 

what does it sound like? my car starts to make this metal on metal scratching noise when i go over bumps. I have a COBB catted dp btw.

 

Hey,
If it is a automatic then it is hitting on the transmission not the crossmember. Sometimes you can get away with just loosening the bolt on the small bracket towards the bottom of the downpipe and pull the downpipe away from where it is hitting then tightening the bolt back up. I have seen people hack away at the car so the DP doesn't hit, please do not do this. The downpipe hitting on anything is NOT good, address this problem as soon as you can.

-Greg

 

i have the carbon ti cat back and the lil flex part was sitting right on my tranny crossmember digging in till i got the longer hangers problem fixed

 

you should have to buy a new one. same thing was happening on my car go under and on one of the screws there should be a tab which you can move the DP over. yuo only need to move it(the DP) over about 3cm or so. but you will see it helps.

 

Well the sound is coming from under me and whenever I start or turn off the car I could hear a knock sound and feel a slight vibration. I'm pretty sure it's the dp hitting the crossmembers.

Also is it normal for my car when accelerating in 1st gear to sound like a chopper (like a fluttering sound)? After 2500 and 3000 rpm the flutter sound goes away. My car sounds like a lawnmower lol Is that normal to sound like that since the dp is a bellmouth design?

 

hey robert,
its your downpipe hitting the crossmember.
I had this problem before with my helix downpipe.
let me guess it thumps pretty hard while shifting aggressively right? and when you turn your car off it feels like a hammer is knocking from under your car.
possible fixes:
grind down the crossmember a little
there is a bracket that holds the downpipe to the tranny. you can undo that bolt and bend the bracket a little and re bolt it back together.
or you can try installing aftermarket exhaust hangers like kartboy hardened hangers.
by the way I got your phone call message and havent been able to get back to you.
if you stop by the shop i'll give your your covers. and if you want I can listen to your car and confirm what the problem is
chris

 

DO NOT cut your crossmember over a part that is fitting shi*ty.

Correct the issue at hand, and not by cutting into a support for your car.

My $0.02

-Noah

 

Werd, bang a dent in the DP

The DP banging on things can also cause phantom knock while tuning, happens with evos pretty often with 3" DPs

 

i had that problem, i just loosen the hanger bolt and pulled the DP away then tightened it back up.