Getting rid of truck sound
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Getting rid of truck sound Question for you guys that have run single setups and then true duals. I'm having a hard time getting my exhaust to not have that individual pulsing noise upon 1/2-3/4 throttle that sounds like an old pickup with straight pipes lol.
I'm beginning to believe it's because of the single 3" exhaust I'm running.
I can't find good videos of true duals with "normal" take offs to see how it sounds. They are either WOT or stationary revs lol.
I didn't have this issue when I ran L/T's catless and 3.5" single on my 04 GTO...but it was also a LS1.
Currently running L/T's, catless, 3" single to a home-made glasspack style muffler under trunk on passenger side with a helmholtz resonator pipe T'd off where OEM muffler would be.
I'm beginning to believe it's because of the single 3" exhaust I'm running.
I can't find good videos of true duals with "normal" take offs to see how it sounds. They are either WOT or stationary revs lol.
I didn't have this issue when I ran L/T's catless and 3.5" single on my 04 GTO...but it was also a LS1.
Currently running L/T's, catless, 3" single to a home-made glasspack style muffler under trunk on passenger side with a helmholtz resonator pipe T'd off where OEM muffler would be.
That sound is from the clashing of fast moving and different air pressures in the y-pipe just prior to where it converges to a single pipe. This sound IMO, is unavoidable if your running a y-pipe and LT's. If you put cats on the y-pipe, it will muffle them a good bit by dampening the air pulses. A straight through muffler like Borla or magnaflow will do little to help the issue whereas a chambered muffler like a Hooker will help a small bit.
There is a ton of science that goes into good exhaust flow. The folks that have a y-pipe and dont have this issue just luckily nailed the ideal lengths of pipe down to the 1/4". This would not be the norm. The TD's are much more forgiving in every respect.
I had that exact same truck/machine gun sound with my old LT's, y-pipe, Borla catback, no cats and that prompted me to go TDs cause it sounded awful. After that, the ugly sound was 100% gone and the exhaust sound was "sweet music". Pics and vid in sig.
There is a ton of science that goes into good exhaust flow. The folks that have a y-pipe and dont have this issue just luckily nailed the ideal lengths of pipe down to the 1/4". This would not be the norm. The TD's are much more forgiving in every respect.
I had that exact same truck/machine gun sound with my old LT's, y-pipe, Borla catback, no cats and that prompted me to go TDs cause it sounded awful. After that, the ugly sound was 100% gone and the exhaust sound was "sweet music". Pics and vid in sig.
Last edited by wrd1972; May 2, 2014 at 02:18 AM.
The glass pack pry isn't helping much IMO. The y-pipe design on these cars can make the exhaust sound very different from one exhaust setup to another even with the same muffler.
About 10 years ago I installed my first set of long tubes, removed the cats and did a hooker catback system. I had a local shop make a off road y-pipe for me. At the time I thought it was built well, but the merge where the two pipes came together at the beginning of the cat back were more of a T instead of a smooth and gradual Y shape merge. I also had that annoying cackle/machine gun sound in the 2400-3500 RPM range. Once I got past that window of RPMs it sounded OK.
When building my 355 I wanted to redo the whole exhaust and the Y-pipe was my main focus. I couldn't find anything on the market designed the way I wanted and after seeing a few other members here having luck with custom Y pipes with a quality merge I knew I had to build my own. I used 3" mandrel bent pieces from Jegs to piece together smooth bends from the LT collector that paralleled together (making the angle in which the pipes come together as small as possible and as close to parallel as possible) before they met with this Flowmaster Merge:
http://www.jegs.com/i/Flowmaster/389...FYdrfgodC10ALA
Followed by a Magnaflow cat back. I have absolutely none of the cackle/machine gun noise at any point of the engine RPM like I had before and this Y should flow much better as well. I also built the exact same exhaust for a buddy running a Hooker catback and it sounded smooth and deep as well without the cackle. Just a side note the Hooker muffler sounds better than the Magnaflow muffler IMO.
About 10 years ago I installed my first set of long tubes, removed the cats and did a hooker catback system. I had a local shop make a off road y-pipe for me. At the time I thought it was built well, but the merge where the two pipes came together at the beginning of the cat back were more of a T instead of a smooth and gradual Y shape merge. I also had that annoying cackle/machine gun sound in the 2400-3500 RPM range. Once I got past that window of RPMs it sounded OK.
When building my 355 I wanted to redo the whole exhaust and the Y-pipe was my main focus. I couldn't find anything on the market designed the way I wanted and after seeing a few other members here having luck with custom Y pipes with a quality merge I knew I had to build my own. I used 3" mandrel bent pieces from Jegs to piece together smooth bends from the LT collector that paralleled together (making the angle in which the pipes come together as small as possible and as close to parallel as possible) before they met with this Flowmaster Merge:
http://www.jegs.com/i/Flowmaster/389...FYdrfgodC10ALA
Followed by a Magnaflow cat back. I have absolutely none of the cackle/machine gun noise at any point of the engine RPM like I had before and this Y should flow much better as well. I also built the exact same exhaust for a buddy running a Hooker catback and it sounded smooth and deep as well without the cackle. Just a side note the Hooker muffler sounds better than the Magnaflow muffler IMO.
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Wow, thanks for the replies fellas.
Yea I can see your point about the Y pipe. I ran a Hooker max flow muffler (non chambered and straight through) and it still had a slight popping noise. I have then switched to the glasspack style and the noise is more prominent. The feature staying the same is the design of the Y.
This is the exhaust I built for my GTO in which I had none of this popping noise, but I didn't know if the popping was a cause of the LT vs LS motor.
This was a 3" Y legs running to a 3.5" back to a 3" magnaflow magnapack right before the tip...all behind L/T's and no cats. Sounded AWESOME at WOT with no popping noise under normal driving.
Granted the Camaro merge is more of a "T" like 97Pontta mentioned. It's something to think about for sure. I could redesign/remake the merge to mimic what I did on my GTO.
Yea I can see your point about the Y pipe. I ran a Hooker max flow muffler (non chambered and straight through) and it still had a slight popping noise. I have then switched to the glasspack style and the noise is more prominent. The feature staying the same is the design of the Y.
This is the exhaust I built for my GTO in which I had none of this popping noise, but I didn't know if the popping was a cause of the LT vs LS motor.
This was a 3" Y legs running to a 3.5" back to a 3" magnaflow magnapack right before the tip...all behind L/T's and no cats. Sounded AWESOME at WOT with no popping noise under normal driving.
Granted the Camaro merge is more of a "T" like 97Pontta mentioned. It's something to think about for sure. I could redesign/remake the merge to mimic what I did on my GTO.
Last edited by smitty2919; May 2, 2014 at 11:23 AM.
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Looks identical to the hooker Y, I used one to make a Y for my OBX headers.
http://www.jegs.com/i/Hooker-Headers...oductId=751902
http://www.jegs.com/i/Hooker-Headers...oductId=751902
Yeah, sorry, I was in a hurry and quoted the wrong pic. I meant that the top one here is what I have, which is a Hooker, it has a nice merge. The other is a Flowmaster.
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Seems like it's a Flowmaster merge or bust lol.
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I cant really comment on the "truck" sound part of this. I am not exactly sure what sound is being discussed.
I have video from the driver's seat that might count as idle with dual exhaust, but I am not sure if people would call it "true dual." It was carbureted.
I doubt I have picture of the exhaust, but if one is needed it will have bad quality.
EDIT
Video removed I do not want a youtube box in this post.
I have video from the driver's seat that might count as idle with dual exhaust, but I am not sure if people would call it "true dual." It was carbureted.
I doubt I have picture of the exhaust, but if one is needed it will have bad quality.
EDIT
Video removed I do not want a youtube box in this post.
Last edited by ChevyOwner; May 4, 2014 at 12:49 PM. Reason: link removed i do not want a video box in this post.
Getting the flowmaster merge is the way to go if you will keep it a single exhaust. I've been running one for years and I don't think I have ever heard anything like you are describing.
Car is stupid loud, CC503, single 4" exhaust using a dynomax bullet for muffler. I do have two other 3" dynomax bullets in my ypipe setup, only because I moved back to PA and wanted it to look like something was there, but it really didn't tame it much, which I liked.
I don't know if I still have the parts list, but someone had posted on here a few years back from this diesel website the parts for going 4" over the axle. It sounds like you just want to replace your ypipe section though so I guess you probably don't need that info anyway.
Car is stupid loud, CC503, single 4" exhaust using a dynomax bullet for muffler. I do have two other 3" dynomax bullets in my ypipe setup, only because I moved back to PA and wanted it to look like something was there, but it really didn't tame it much, which I liked.
I don't know if I still have the parts list, but someone had posted on here a few years back from this diesel website the parts for going 4" over the axle. It sounds like you just want to replace your ypipe section though so I guess you probably don't need that info anyway.
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Well I ended up putting my full size borla muffler (one that comes with the adjustable CB) in addition to my home made glasspack on passenger side and it smoothed out the tone a lot. Not much left of the truck sound.
I also HATE drone...which this exhaust now has lol. If I remove the glasspack I know it will o away since I bought the car with just the borla catback...it just wasn't aggressive enough for me.
I also have a hooker max flow 3" muffler I can swap on in place of the borla...that's happening tomorrow and will see how it turns out.
I also HATE drone...which this exhaust now has lol. If I remove the glasspack I know it will o away since I bought the car with just the borla catback...it just wasn't aggressive enough for me.
I also have a hooker max flow 3" muffler I can swap on in place of the borla...that's happening tomorrow and will see how it turns out.