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8-4-1 Headers (Video)

TreeFiddyAre

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@TreeFiddyAre did you approach the company with this topic? Pursuing a refund? Providing feedback?
Yep… and they basically told me to pound sand. 😂 I even asked for a partial refund and got a hard “nope,” so I’m officially married to this expensive science experiment.

The good news: I just got the car back with the new setup and the sound is sooooo much better. Like, night-and-day better. The Voodoo finally sounds like it remembers it’s a flat-plane crank engine instead of a stainless-steel weed trimmer.

The bad news: apparently the car decided I wasn’t allowed to have a win this week.

After about 10 minutes of driving, when I turn the wheel to roughly the 2:30 position towards the right, I get a noticeable vibration. If I keep turning toward about 3 o’clock, the vibration suddenly disappears. It seems to be speed-dependent, and the vibration feels like it’s coming from under the dash near the steering column/stalk area.

My best guess right now is that it feels almost like the electric power steering assist motor is briefly applying a strange load or oscillation. The weird part is the car is throwing zero codes.

For context, the shop said they disconnected the battery and cleared the P0300 code that appeared immediately after the Concept exhaust setup was installed. Now that issue is gone, but this steering vibration showed up after the first 10-minute drive.

So the current scorecard looks like this:

✔ Exhaust sounds dramatically better

✔ P0300 appears gone

❌ Steering wheel now thinks it’s auditioning for a massage chair

❌ My blood pressure is probably making more horsepower than the car at this point

Before I start throwing parts at it, what would you guys check first?

Curious if anyone has seen a speed-dependent steering vibration with no codes after a battery disconnect or exhaust install. The timing is suspicious enough that I don’t think it’s a coincidence.
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GregO

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the vibration feels like it’s coming from under the dash near the steering column
My guess is the stainless headers are contacting something. 300 series stainless will expand in diameter and especially length when heated.
10 minutes of run time is enough time for the system to start expanding.
 

WItoTX

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Did they pull the subframe to do the headers? If the headers were touching the steering column, I'd expect a knock code of some sort. But yeah I'd definitely start at headers and then look at wheel bearings, especially if they are factory.
 

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TreeFiddyAre

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My guess is the stainless headers are contacting something. 300 series stainless will expand in diameter and especially length when heated.
10 minutes of run time is enough time for the system to start expanding.
Ehhhh dont think so , when the car is at idle and i turn the steering wheel the vibration is slow but it I turn the wheel at 20mph the vibration is a high frequency, 40mph higher,etc.... I'm confident it has something to do with artificial weighted steering function
 

TreeFiddyAre

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Did they pull the subframe to do the headers? If the headers were touching the steering column, I'd expect a knock code of some sort. But yeah I'd definitely start at headers and then look at wheel bearings, especially if they are factory.
I'm not sure if the lowered the subframe but I spoke to them already and Monday it goes back. The vibration/feeling/sound isnt that of a wheel being out balance its a more deliberate one and it feels like its coming from the electric gizmo that creates the weighted feel of the steering and as speed increase the steering wheel tension varies... sorry I'm struggling to try and describe it lol
 

TreeFiddyAre

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Here is a quick vid , it’s very faint since I am driving slow but as speed is increased the feeling in the steering wheel and the sound is far more pronounced, it sounds like it’s coming from the base of the steering stalk just under the dash . Towards the end of the vid you can hear it a bit better.. once up to driving speeds it’s mega annoying and makes me want to park the car … again :( . I want to enjoy the dang exhaust setup damn it lol , which is wayyy better than I expected btw - minimal rasp
 

TreeFiddyAre

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So your car had this issue before the most recent header swap ?
Zero issue minus the previous exhaust setup and the p0300 code that populated after the install



 

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TreeFiddyAre

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@TreeFiddyAre sorry that you took the plunge and it didn’t work out (I agree it sounds terrible), but hopefully this new setup sounds killer!
I really really really like the sound … to my surprise the rasp is no where near as bad as I expected and to be honest there really isn’t any super happy about that to say the least .
 
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A_Bau3

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My guess is we were all hoping for something along these lines, but it clearly didn’t come to fruition. And this isn’t even a Voodoo, it’s a Coyote.
I really really really like the sound … to my surprise the rasp is no where near as bad as I expected and to be honest there really isn’t any super happy about that to say the least .
Post a vid when you get the chance. I think I’ve always been drawn to ARH’s full system with cats/res because it took away all the rasp.
 
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A_Bau3

A_Bau3

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I think we were all hoping for something along the lines of this

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