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Discussion Starter · #1 ·
So if you have read my problems with my stock BOV, one of the problems I didn't list is excessive gas pedal vibration. I don't remember having the gas pedal vibrate at all since installing my BOV. This problem only started after I reinstalled my stock BOV, so that's the reason for my theory.

But today, I was re-installing my raceppipe on my TurboXS Stealth Back exhaust, and taking the high flow cat off. Well anyone knows that this exhaust system comes with a mouting bracket that must be bent in order for it to fit properly. This bracket must be mounted to the stock location bracket that is bolted to the rear of the transmission. Well as I was dis-assembling the high flow cat section, I found my stock location bracket had snapped in two. So I am thinking that this might be the cause of my gas pedal vibration.

Since the exhaust is no longer secured to a mounting bracket it can bounce side to side, and could cause my gas pedal vibration. Couldn't it. The gas pedal never vibrated before last week. And I have no idea how it could have broken.

Good thing I took a machine shop course at school this semester. It will come in handy when I have tomanufacture a new bracket for my car.


 

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Check your motor mounts. A motor mount problem will produce pedal vibes, and motor mounts tend to snap exhausts - or in your case brackets. Might be a motor mount that caused both problems.
 

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I don't have WRX experience here, but my other car had wicked vibrations due to a simple broken exhaust mount. I fixed the exhaust hanger and the vibrations went away completely.Of course it never hurts to check the motormounts. JMHO.
 

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Discussion Starter · #6 ·
SD_GR said:
Check your motor mounts. A motor mount problem will produce pedal vibes, and motor mounts tend to snap exhausts - or in your case brackets. Might be a motor mount that caused both problems.
Could you point me in the right direction of pictures and or suggestions as to how to find my motor mounts? And If I should replace them, should I go with polyurethane or polygraphite pieces? I had a polygraphite set of front end bushings on my Firebird, and they worked very well.
 

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Sure here's a pictorial how-to link:
http://www.scoobymods.com/forums/showthread.php?s=&threadid=470&highlight=motor+mount

I don't know what to tell you about the material of a replacement mount - see if yours is truly messed up first. It could simply be the exhaust mount that failed - the motor mount causing exhaust problems is a possibility. It's worth exploring since all you have to do is look around, and hopefully you won't need any new motor mounts to begin with...

Just eyeball it and see if there's any merit to my suspicion about the motor mounts. If I'm compeltely wrong, no worries. If you decide to get under it *do* be safe.
 

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Discussion Starter · #9 ·
I changed my oil today, so I go underneath the car after the oil change and checked my mounts. The engine mounts are fine. No visual wear or cracks. I also check the tranny mount. Again, no visible wearing or cracks. So I assume it just may be my exhaust bracket. I need to hurry up and fabricate one. The gas pedal vibration is rather annoying.

Thanks everyone for the suggestions though.
 

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Discussion Starter · #10 · (Edited)
So last week I put my new Machine Shop skills to work,as I just got finished taking a basic class in Machining. So I took a scrap piece of hard steel plate from work, made a template from the stock broken exhaust mount and cut it on the bandsaw. Then marked the holes, used a center drill to get them started, and then drilled them through. I then put the bracket on the vise, marked it in the exact spot it needed to be bent at, and took a rubber mallet to it. I then took it to the buffing wheel, and polished it up, but the pictures I took of it don't do my polishing skills any justice.

So I got under the car, and of course it didn't fit the first time. The upper portion of the bracket (part with 2 holes) needs to be the exact size as the stock one, since it has to fit between two bolt heads. I also needed to grind down some material on the lower portion of the bracket to make it fit past one of the bolts on the 2 bolt flange of the TurboXS downpipe. So I brought it back to work, re-grinded it to size, re-polished it, and installed it. I reinstalled it with the 2 bolt bracket that originally came with the TurboXS Stealth back. So it is almost the exact same setup as I set it up from the beginning, but the new bracket I made is .025" thicker steel than the stock bracket. It seems to have taken almost 75% of the gas pedal vibration away. The other 25% of gas pedal vibration is hardly notiecable anymore.

I just wanted to share my story with you all.



 

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Well, I had a squeak coming from down around that area, and remembered this thread. When I crawled under tonight, I saw what I expected. The mount that I made (bought my stealthback used and it didn't come with the bracket) had snapped in two. Looks like I'm gonna have to call TurboXS and get them to ship me a real one.
 

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nice machining job!
 

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to check motor mounts-

1.Put e-brake on
2.Pop hood
3.Have friend look at engine
4.put in first and release the clutch slowly so the engine is put under load
5.put in reverse and do the same

If the engine is moving than an inch fore and aft, then you need to mounts. There are 2 mounts underneath and one pitch mount on top under the intercooler.

Corey
 

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Well, I just discovered this afternoon that the same metal hanger on my Turboxs stealthback broke again. It's the piece in the upper right corner in KurleeDaddy's pic.



I've helped a couple different people out with their exhausts and I couldn't believe how nicely some of the other mfg's hangers line up with that bracket. I'm seriously thinking about tossing this POS and getting a different brand. :mad:
 

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i tell you that is the weirdest crap i have ever seen i have never known an exhaust mount to cause "pedel vibrations" A motor mount i can see that you know something that might also cause a problem i have seen a tire vibration cause a vibration in the front of the floor plan which seems like it's coming from the pedel. huh thats odd.
 
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