Clanking sound after header and cat install

[usnavydoc]

I finally got around to installing my Borla short headers and Solo high flow catalytic converter. My mechanic said that he was barely able to get the cats to fit because my Corsa exhaust was spot welded (to keep thieves from stealing it) and he wasn't able to do much in terms of adjustment.

The car sounded fine in the beginning, but 10 minutes on the road and it sounds like I have a popcorn cooker under the car. Lots of clanking when the car moves, and its even louder when I go on reverse at low speed - it almost sounds like a high pitch rumble, and not the good kind of rumble.

What do you guys think it is? My mechanic and a friend who works on cars thinks it is the exhaust pipe hitting the chassis because it is too close to it. I was told the factory cats are designed in a way that it keeps it from vibrating or becoming loose, a feature I don't have with aftermarket cats.

Engine sounds great other than the constant clanking. It feels like someone is punching my seat from below. I am taking it to the muffler shop tomorrow to get them looked at and adjusted if needed. I hope it is something as simple as an adjustment of exhaust pipe position. I don't know if I am being paranoid or never noticed it, but it looks like the engine block is a bit off center, leaning towards the left.

[SUX2BU]

Your mechanic did a crappy install job. Exhaust should not be rubbing on anything.

[usnavydoc]

I can't hold it too much against him since the exhaust was welded down and he didn't have the necessary equipment to cut the welding. Hope it isn't something more serious.

[SUX2BU]

Originally Posted by usnavydoc

I can't hold it too much against him since the exhaust was welded down and he didn't have the necessary equipment to cut the welding. Hope it isn't something more serious.

Not sure I understand. Did you have used parts installed that were welded together?

[usnavydoc]

I originally had the Corsa exhaust installed, which was spot welded, with the headers and catalytic converter left stock. Today, I had the aftermarket headers and cats installed. The mechanic couldn't adjust the exhaust to the best position because it was welded. I am going to a muffler shop tomorrow to have the parts adjusted so it isn't touching the car frame and then spot re-weld them - hopefully that fixes the issue.

[Sebastian]

i just installed headers with cats and have a catback as well. seems that the exhaust is just misplaced. i dont have any problem with space for exhaust or the pipes. best thing as u already said is go to exhaust shop and let them have a look.

[MA2010SS]

Originally Posted by usnavydoc

I originally had the Corsa exhaust installed, which was spot welded, with the headers and catalytic converter left stock. Today, I had the aftermarket headers and cats installed. The mechanic couldn't adjust the exhaust to the best position because it was welded. I am going to a muffler shop tomorrow to have the parts adjusted so it isn't touching the car frame and then spot re-weld them - hopefully that fixes the issue.

He should have cut the spot welds, then he would have all the adjustments in the world to make it not bang the floor boards

[bluetorp]

Spot welded to keep thieves from stealing it?

I'm really not trying to be an ass, I just thought that was funny. This can't really be a problem, can it? It would be quicker and easier to just steal the whole car.

Anyway, it does just sound like the cats are hitting the car. Spot welds are easy to cut, so I'm not sure why this mechanic didn't just do that in the first place. If you're taking it in to an exhaust shop, they'll certainly be able to cut the spot welds and get everything aligned properly.

[justa25thTA]

your exhausts NEEDS to move. You know that the engine moves around right? And if the exhaust is bolted to the engine, it will need to have the ability to move as well. Why do you think you have rubber hangers?

[Ject]

Originally Posted by justa25thTA

your exhausts NEEDS to move. You know that the engine moves around right? And if the exhaust is bolted to the engine, it will need to have the ability to move as well. Why do you think you have rubber hangers?

I think you miss understood.
It isn't welded to the car, It appears he is saying that the exhaust was spot welded together instead of using band clamps. Thus meaning there is no adjustment ability unless the welds are cut.

[usnavydoc]

Originally Posted by bluetorp

Spot welded to keep thieves from stealing it?

I'm really not trying to be an ass, I just thought that was funny. This can't really be a problem, can it? It would be quicker and easier to just steal the whole car.

Anyway, it does just sound like the cats are hitting the car. Spot welds are easy to cut, so I'm not sure why this mechanic didn't just do that in the first place. If you're taking it in to an exhaust shop, they'll certainly be able to cut the spot welds and get everything aligned properly.

Unfortunately I have friends who have had their mufflers stolen by thieves while parked in a public garage. Its easier to just spot weld them. If they take the car oh well hopefully I can be there in time to stop them.

[IndeedSS1]

The stainless mesh inside of the SOLO cats are welded in many places to prevent any breakage or rattling. It is extremely unlikely that it's internally those cats.

[usnavydoc]

Got them fixed. Sound great. Best thing is the muffler shop did it for free. Lesson learned. Never spot weld unless the whole exhaust system from intake to muffler is done - and then only if one is sure they will stay with the setup. Shop had to heat pipes to bend them away from floorboard.