Eliminate LS rasp

[sdubfid]

Just got my swap on the road.

hooker blackheart 3” stainless ls swap exhaust with x-pipe.

sounds great at idle but around 2500rpm there is a really annoying raspyness to the sound.

Any suggestions how to eliminate this? Replace x pipe with H pipe? High flow cats? Resonators? Different mufflers?

I am ok if the sound is a little quieter but it really sounds like a civic with a v8 sometimes.

[andrewb70]

Just got my swap on the road.

hooker blackheart 3” stainless ls swap exhaust with x-pipe.

sounds great at idle but around 2500rpm there is a really annoying raspyness to the sound.

Any suggestions how to eliminate this? Replace x pipe with H pipe? High flow cats? Resonators? Different mufflers?

I am ok if the sound is a little quieter but it really sounds like a civic with a v8 sometimes.

Sadly the mufflers that Holley uses in those systems are not the best. Worse yet, they will get louder as time goes on.

I recently replaced the V304 Hooker mufflers with large case (19 inches) Borla ProXS mufflers and I am very happy.

Andrew

[F-Body International]

I don’t really get into brands on this subject but I always use and recommend packed mufflers myself. I’m not sure if you have chambered but make sure you have a packed muffler to keep it somewhat quiet (by comparison).

[showdog75]

Another vote for the Borla ProXS. I took off a pair of Pypes Street Pro's that were very raspy tinny sounding. The Borla's are perfect.

[sdubfid]

After lots of googling and YouTube watching it seems borla pro xs would be a good solution to try. Thanks

[sdubfid]

Installed the borla pro xs 3” today, they are quite a bit heavier than the blackheart mufflers maybe more packing. But they are also much quieter at idle. Snowed today so have gotten a chance to see if the rasp is gone.

[68Formula]

I think you're going to like those Borlas. If that doesn't completely do it, I'd try replacing the X-pipe with an H-pipe.

[sdubfid]

I think you're going to like those Borlas. If that doesn't completely do it, I'd try replacing the X-pipe with an H-pipe.

got it out for a test drive. It is much better but still not there yet. I guess my next options will be h pipe or high flow cats

[Mr Nick]

I'm surprised that one brand of straight through perforated core muffler can sound that much different than the same type of muffler by a different brand.

My SBO has a rasp right around 2,500 - 3,000 RPM as well, mostly when deaccelerating (between gears) and I'm tempted to swap out the Hooker Aerochambers for something else. I really like the way the car sounds, with the exception of the rasp which is right at my cruising shift point. :hand:

[shelteredchevelle]

On my V I had a Stainless works exhaust with x-pipe in back of American Racing 2" headers and it was OBNOXIOUS. I cut in a pair of 22" Vibrant resonators and that made it sound really good, but still loud. It didn't rasp or drone at all, just kinda loud. I ended up going back to stock mufflers, gutted cats, and 16" Vibrant's. That was quiet until you romped on it. I sold the car with that setup.
My current build has a 572 in it, so that doesn't count here.
My latest has a LSA with LS7 manifolds into 3" with an Xpipe and I'm thinking of going with the Borla ProXS too. I don't have much room at all, so resonators might be out. The cats have already been tuned out and gutted, if it's rude, I'll put green cats back in and tune it for them.

[130fe]

I have been considering the Holley headers and exhaust setup (for the DSE suspension- on my list of upgrades). What is the difference with/without the resonator? Louder, quieter? Any info would be appreciated.

https://www.holley.com/products/exhaust/exhaust_systems/hooker_blackheart/parts/705013124RHKR

VS

https://www.holley.com/products/exhaust/exhaust_systems/hooker_blackheart/parts/705013109RHKR

[sdubfid]

I'm surprised that one brand of straight through perforated core muffler can sound that much different than the same type of muffler by a different brand.

My SBO has a rasp right around 2,500 - 3,000 RPM as well, mostly when deaccelerating (between gears) and I'm tempted to swap out the Hooker Aerochambers for something else. I really like the way the car sounds, with the exception of the rasp which is right at my cruising shift point. :hand:

this surprised me as well. The Holley vs borla are both the same size straight through 14” mufflers with the borla being significantly quieter/minimizing higher frequencies. In 6th gear I’m at 1500rpm at 60mph and there’s no drone or anything, it’s quite comfortable other than the big hole around my shifter.

[andrewb70]

If y'all check out some of the recent builds done by The Roadster Shop, you will see a heavy use of Borla mufflers, resonators, and J-pipes.

Andrew

[monteguy88]

I know this is an old thread, but were the Borlas a good swap? I have the hooker 3” system on my swapped 6.0 and the drone on the highway at 3000 rpm is unbearable. Looking to make a muffler swap.

[hp jnkey]

Install Drone tubes

[andrewb70]

I know this is an old thread, but were the Borlas a good swap? I have the hooker 3” system on my swapped 6.0 and the drone on the highway at 3000 rpm is unbearable. Looking to make a muffler swap.

You may have a hard time finding mufflers that are quiet at 3000RPM. In my Cougar I go down the highway at 75mph at 1700RPM and you can barely hear the engine. I have the Borla ProXS large case mufflers.

Andrew

[79 Camaro]

You might try Dyna Max turbo mufflers. I like and use them on my LS swaps.

[monteguy88]

Well, my Borla PRO XS are out for delivery today. I’ll update the post on whether or not they were worth the swap from the Hooker mufflers that come with the otherwise really nice and well made Hooker exhaust.

[monteguy88]

100% better, no more rasp or drone. The Borlas sound way crisper too. Only slight issue I ran into is the Borla mufflers were roughly 3/4” shorter than the Hookers, so I had to cheat a bit on some of the gaps, but it worked out great.

[68Formula]

Awesome. Thanks for deeding back to the group.

[monteguy88]

No problem! I’m not sure how to upload pics and videos on here otherwise I’d share some.

[67-LS1]

Drone and Rasp are two different issues.
I just changed my X pipe to an H pipe and the tone dropped noticeably. Not as raspy as before.

[monteguy88]

Check out my Instagram account @monteguy88. I made a video comparing both mufflers back to back for anyone interested.