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73-87 Chevy _ GMC Trucks => Performance => Exhaust => Topic started by: crazymudder on February 19, 2007, 09:40:00 pm

Title: No tailpipe after muffler?
Post by: crazymudder on February 19, 2007, 09:40:00 pm: On my 86 gmc half ton 305, the previous owner ran true dual exhaust with what sounds to be a mild turbo muffler. when they ran it out the back, they left no room for the spare tire. I want to put the spare back under and also want to make it a little louder. The way they bent it over the rear axle pinched the exhaust a little. I was thinking about cutting the pipe right after the muffler. Is this a good idea? The pipe is 2 inch. It isn't stainless and has some surface rust. I think the reason for sounding like a "mild" turbo is because of the 2 inch pipe all the way to the rear bumper. The muffler itself is just behind the gas tank. Please give me any input of past experience etc. Thanks
Title: Re: No tailpipe after muffler?
Post by: Lt.Del on February 19, 2007, 09:52:00 pm: The longer pipe, or lack thereof, will not change loudness much if any. I have 2 inch pipe on my 91 suburban. At first, I had it installed without a muffler, just a cat and ran the pipe all the way past the rear wheel. Boy was she loud. I had to go back and put a muffler on it it was just toooo loud.

Now on my 79 pickup with 383 stroker I had new exhaust, a little smaller diameter than 2", whatever that is, and had a new cat (round cylinder type) put on without a muffler. From the cat it split to duals to both sides just in front of rear wheels. She sounds great, not too loud because of the smaller diameter of the pipe. She sounds perfect.

The moral of the story: I don't think the length of the pipe makes it sound louder/quieter, more importantly, it is diameter of the pipe. It also depends on type of cat and whether you have a muffler or not.
SgtDel
aka "Andy"

www.delbridge.net

1979 Big 10 383 stroker
1991 Blu 'Burb 3/4 ton 4x4
Title: Re: No tailpipe after muffler?
Post by: xtreme80 on February 21, 2007, 10:12:00 am: I've got true duals with 2.5" pipes all the way back with no mufflers, exiting out just in front of the left rear tire and boy is she loud!

I you're wanting to cut those pipes off, go for it, but try to get a turndown tip for your muffler. If you don't, it's gonna blow that exhaust right back on everything under your truck, and it'll also drone a little more.
Title: Re: No tailpipe after muffler?
Post by: crazymudder on February 21, 2007, 09:05:00 pm: Thanks for the help guys. I cut them off right after the muffler. It isn't much louder if any but at idle it is much deeper. It only drones at idle. I'll probably eventually get turbos with downward tips. Now I can get my spare back under there. It'll be a hassle when I need to get it off, but I got tired of having it in the bed. Also, any ideas for cheap turbo mufflers that sound good but without being ridiculously loud at idle? Thanks for the help.
Title: Re: No tailpipe after muffler?
Post by: jseifert on February 25, 2007, 10:26:00 am: On lowered trucks, it seems to me that a turndown right behind the muffler makes a difference... Maybe I am just hearig thing, but it would make sense to me that an echo off of the ground would be present in that situation...
Title: Re: No tailpipe after muffler?
Post by: xtreme80 on February 27, 2007, 09:51:00 am: It will echo off the ground more, but the main thing is, it won't rattle everything under the bed and turn everything black under there.

My old truck had an exhaust that dumped right before the axle, and having the turndown on there was a night and day difference to the noise inside the cab. It really didn't make a difference outside, but it was so much quieter inside.
Title: Re: No tailpipe after muffler?
Post by: 78heavyhalf on October 13, 2012, 11:29:37 pm: I want to do that too I was just wondering if it will be a little dangerous from the back fire by the gas tank I ain't running cats so it pops when I put it in low gear
Title: Re: No tailpipe after muffler?
Post by: Fairlane514 on October 14, 2012, 09:50:49 am: Summit has their house brand mufflers that are pretty cheap. I have the street/strip mufflers and a 2.5 system and it sounds very nice, not too loud not too quiet.
Title: Re: No tailpipe after muffler?
Post by: thirsty on October 14, 2012, 10:35:12 am: I'm in favor of having tailpipes. At the very least have some downspouts. Where I live beds for these trucks are getting very rare now. I hate to see the moisture from the exhaust always lingering underneath the beds when the trucks aren't moving.
Title: Re: No tailpipe after muffler?
Post by: Stewart G Griffin on November 08, 2012, 07:42:15 pm: i think it's always best to get the exhaust out from under the car----be it sidepipes, bend out behind the rear wheels, or all the way to the back bumper. The risk of getting carbon monoxide into the cab is too great.
Title: Re: No tailpipe after muffler?
Post by: Irish_Alley on November 10, 2012, 09:21:22 am: in a truck as long as it goes past the cab your good you dont have to worry about carbon mono once it passes a couple inches past the cab. if i can remember right in delaware as long as it passes the cab and have a cat and muffler on your good. i loved 45s right before the rear tires kind of gave it a hot rod look. on my 79 i have turn downs with only mufflers right after the cab. no problem with sound but i ended up just cutting them off and going with open headers cause it doesnt see that much road. but i do plan on doing 45s on my 79 when im ready to start working on her again instead of tearing her up. but anyway why we posting on such a old topic lol