Drilling holes in exhaust system

Mannix

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:facepalm::facepalm::facepalm:
I've never wanted to rescind a thread so bad in my entire life....it was meant to be a simple question concerning a 5 minute job....if I wanted to spend hundred of dollars or tear apart my exhaust system, I'd have asked that question specifically.....never mind. I feel as if someone needs to give me a dose of my own medicine with the following....

 

Rockport

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I pull the baffles out of the exhaust pipes of all my Harleys.
Makes them VERY loud.

Just be aware that any hole you drill will create a rust spot.
You could just buy a high performance exhaust pipe.
And very inconsiderate of others.
 

JohnnyTheFox

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:facepalm::facepalm::facepalm:
I've never wanted to rescind a thread so bad in my entire life....it was meant to be a simple question concerning a 5 minute job....if I wanted to spend hundred of dollars or tear apart my exhaust system, I'd have asked that question specifically.....never mind. I feel as if someone needs to give me a dose of my own medicine with the following....


I would say if you want to, go for it. The only possible issues are not passing inspection and of course as someone else's mentioned rust. Since the holes would be on the back side of the converter I wouldn't see a problem. Not sure where you live but Wonder how strict of an inspection they have. When they had them here it would have certainly passed, even a car I had with the catalytic converter hollowed out still passed. But that is Oklahoma:laugh:
 

CalPolyTechnique

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I pull the baffles out of the exhaust pipes of all my Harleys.
Makes them VERY loud.

Just be aware that any hole you drill will create a rust spot.
You could just buy a high performance exhaust pipe.
Do you buy all your Official Harley gear off the rack?
 

Fritsch_the_cat

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Wonder how strict of an inspection they have.

That all depends. I'd say most places would run it right through, but you never know. I've had a guy refuse to pass mine because it had a low rear tire. If you find an a-hole like that, you could be on the hook for a new exhaust system. The thing is now, in Texas, if your vehicle fails inspection, you have to return to the same place that failed you to get it passed, which means you have to fix whatever they say is wrong. Also, no inspection, no registration either.
 

Cowpolk

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I would say if you want to, go for it. The only possible issues are not passing inspection and of course as someone else's mentioned rust. Since the holes would be on the back side of the converter I wouldn't see a problem. Not sure where you live but Wonder how strict of an inspection they have. When they had them here it would have certainly passed, even a car I had with the catalytic converter hollowed out still passed. But that is Oklahoma:laugh:
In Texas a hole in the exhaust is an instant fail
 

Runwildboys

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I would say if you want to, go for it. The only possible issues are not passing inspection and of course as someone else's mentioned rust. Since the holes would be on the back side of the converter I wouldn't see a problem. Not sure where you live but Wonder how strict of an inspection they have. When they had them here it would have certainly passed, even a car I had with the catalytic converter hollowed out still passed. But that is Oklahoma:laugh:
He could always solder the holes when he goes for inspection. :muttley:
 

Runwildboys

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That all depends. I'd say most places would run it right through, but you never know. I've had a guy refuse to pass mine because it had a low rear tire. If you find an a-hole like that, you could be on the hook for a new exhaust system. The thing is now, in Texas, if your vehicle fails inspection, you have to return to the same place that failed you to get it passed, which means you have to fix whatever they say is wrong. Also, no inspection, no registration either.
In CT, we don't have to get inspections unless we buy an older vehicle. If you bought a new car 25 years ago, it's still okay, unless someone buys it from you, then they have to have it inspected. Of course, emissions is every 2 years.
 

LACowboysFan1

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Depending on the car and engine if enough back pressure is lost you actually lose performance. There is a reason why too big of an exhaust can actually be detrimental, back in the day of Sport Compacts, 3 inch exhaust was usually the cutoff for NA engines with a lot of work, and 3"+ was meant for forced induction cars.

Need to keep the physics of the pipes in mind. a 20% increase in pipe diameter gives a 40% increase in flow. You're right, it's easy to go too big....
 

nobody

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Vtwin

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:facepalm::facepalm::facepalm:
I've never wanted to rescind a thread so bad in my entire life....it was meant to be a simple question concerning a 5 minute job....if I wanted to spend hundred of dollars or tear apart my exhaust system, I'd have asked that question specifically.....never mind. I feel as if someone needs to give me a dose of my own medicine with the following....


Other inexpensive options to make you truck louder are...

Remove exhaust pipe from muffler outlet. Get ya a half inch or so diameter pipe and a BFH and drive it though the muffler. Install exhaust pipe.

or

Swap the muffler out for a cheap glasspack/cherry bomb.

I think you are you are required to add a set of swinging nuts to your trailer hitch if you do these mods.
 

Runwildboys

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Other inexpensive options to make you truck louder are...

Remove exhaust pipe from muffler outlet. Get ya a half inch or so diameter pipe and a BFH and drive it though the muffler. Install exhaust pipe.

or

Swap the muffler out for a cheap glasspack/cherry bomb.

I think you are you are required to add a set of swinging nuts to your trailer hitch if you do these mods.
And turn the rims the wrong way.
 

LACowboysFan1

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What's the point of being loud and obnoxious? I can't think of a single positive from it. If it increased a car's power tremendously, or it's gas mileage, sure. . But just to be loud? Why?

All you do is make people dislike fast cars. I love the sound of a well-tuned, well sounding car. But it doesn't have to be all that loud. And if you must be loud and obnoxious, do it on the open road or in some deserted warehouse area. Of course, there's no one around to see them, no thrill there.

Just the past weekend my family and I were in Houston trying to find a restaurant, a bunch of Lambos and Porches with what appeared to be open exhausts were revving up their engines in the middle of the shopping area, so loud first of aa my ears hurt (and I've been to many an NHRA drag race, those cars are even louder, so I'm used to loud engines) and we couldn't even be heard when we tried to talk.

It's only about "look at me, look at me", has NOTHING to do with showing off your high-priced car....
 

Roadtrip635

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What's the point of being loud and obnoxious? I can't think of a single positive from it. If it increased a car's power tremendously, or it's gas mileage, sure.. .But just to be loud? Why?
In the OP's application that's all the exhaust cutouts are likely to do, make it louder.... yep just to be loud. Now if it's used on a modified, tuned engine, there can be performance increases, a little more HP and torque. It could be an option for someone that uses the car on the streets, but also takes it on the track, you keep the civility for street use and get a little added power for those track days.

Now making a stock engine louder is a little silly, but the sound of a modified, tuned engine at full throat is a pretty glorious sound. Of course, context is everything, at the track or a nice desolate piece of road, it's great, but at the supermarket or a school zone, then you're just being a jerk.......lol
 

trickblue

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If you're going to do it and least do it right and get an exhaust cutout kit. It will be completely street legal and quiet, but loud and obnoxious at the press of a button.

https://www.summitracing.com/search/part-type/exhaust-cutouts

Cutouts are great and you can control the sound via remote, but they aren't legal in all states such as Texas...

Technically here, you can't even put a dual exhaust on your truck unless it was designed by the manufacturer...
 
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