Drilling vents into exhaust
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Drilling vents into exhaust Hey guys. been snooping around here a while and this forum seems to have the most knowledgeable people.
I have a 99 Z28 a4. 100% stock. I had this idea to drill a few 1/2 to 1 inch holes right after the Y turns into a single pipe before the rear axle. I'm looking to get possibly a better exhaust flow without making the car unreasonably loud. I'm thinking if I remove the clamp where the Y is, I can drill a line of holes along where the clamp would go, so if it turns out to be horrible, I can just reattach the clamp over the small holes. I really don't mind if the car is a bit louder.
It can't sound that horrible since its behind the cat right? Any thoughts?
I have a 99 Z28 a4. 100% stock. I had this idea to drill a few 1/2 to 1 inch holes right after the Y turns into a single pipe before the rear axle. I'm looking to get possibly a better exhaust flow without making the car unreasonably loud. I'm thinking if I remove the clamp where the Y is, I can drill a line of holes along where the clamp would go, so if it turns out to be horrible, I can just reattach the clamp over the small holes. I really don't mind if the car is a bit louder.
It can't sound that horrible since its behind the cat right? Any thoughts?
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The thing about the E-cut is it's an expensive application. I'm kinda limited to doing stuff with the tools I have already. Smog laws are not a factor for me. I'm just curious as to how it might sound after. If it turns out to be fail, I'll just weld the holes closed
TECH Fanatic
Joined: Aug 2011
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From: Marengo, Ia
I would guess that it would make the car sound like a POS with a rusted out exhaust. Also with the holes that far forward it would cause an annoying exhaust drone in the interior. If you want to do something thats free look up the free ram air mod.
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Is it really that far forward? Maybe a bit closer to the muffler then. My current budget is $0 so a cutout is not an option at the moment. I'm assuming a manual cutout is the same as E, but its perma opened. Isn't that essentially what I'll be doing? In that case I might just do 2 or so holes at 1.5 in... I could've sworn I saw someone who had the E-cut where the Y is, right where I wanna do it. I might have even seen one before the cat. I wonder how that sounds in the car
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I didn't realize asking for people's thoughts on my DIY project was a stupid question. Why isn't it stupid to do a cutout or gut you cats? I'm just talking about drilling a few one inch holes in the back of my Y. All I want is to see if anyone else tried this on a stock F-body exhaust.
Someone wants to see my before and after video
I'm gonna do it
Someone wants to see my before and after video
I'm gonna do it 
Staging Lane
Joined: Jan 2014
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its a ******* stupid idea because a few small holes will make it sound terrible. itll sound like the exhaust is rusted out and need replacing. a e cutout will sound completlely different to what you are looking to do. if you cant afford to mod it leave it alone. better yet sell it and buy a corolla. milo tins are free.
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Actually I have a corolla. Its for sale. I myself have only driven and worked on 4th gen Camaros. you sound like you know a thing or two about Corollas. You should buy it. its a 2000. 140k and counting. Yours for $8,000.
So why does a cutout sound different exactly? because the entire pipe is open? Like I said, I'm not planning to do an exhaust leak-sized hole. I'm talkin several holes over one inch in diameter in close proximity to each other
So why does a cutout sound different exactly? because the entire pipe is open? Like I said, I'm not planning to do an exhaust leak-sized hole. I'm talkin several holes over one inch in diameter in close proximity to each other
There is a reason you didn't find any results when you did a search on here. I'd say save up for a manual cut out (cheapest option) and call it a day till then. Go on youtube if you'd like to hear sound clips with it opened and closed.
Good luck
Good luck
If you want it to be louder and flow better without spending money, just remove the muffler. The cats will keep it at a tolerably volume but it will be fairly loud. Later you can buy an aftermarket muffler to install in place of the old one if you want.
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