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Rasp Question ???

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Old 07-04-2006, 05:03 PM
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Default Rasp Question ???

I have Hooker Cat-Back now and plan on getting Pacesetter LT + Pacesetter Y pipe.

I have done a little reading and saw that running a Catted Y pipe may give me less rasp sound than running no cats. ???

Any truth in this? Will it quiet it down a lot? any loss in power between the 2?

Bottom line is I want no Rasp.

Thanks
Old 07-04-2006, 05:36 PM
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well with the hooker catback you will have no rasp. Having the cats you may lose 5 hp but nothing big. Hooker catback has been known to not have rasp even with the ORY so ur good to go. I just ordered the hooker catback for my ride and i have the same setup you do...LT's and Catted Y.
Old 07-04-2006, 09:40 PM
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Maybe we should define where rasp originates. LS1's are gonna have or at least tend to have some rasp anyway. The hooker is a pretty "raspless" in my opinion too. The charateristics of the aluminum block is a main source of rasp due to its resonance. Having open exhaust is going to let it show it's ugly head even more-so. That is why you hear the "keep your cats" saying when refering to "Will I have rasp with ORY, LT's, and bullets?" questions.
Old 07-04-2006, 09:41 PM
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I didnt think that Pacesetter had a y-pipe.
Old 07-04-2006, 09:55 PM
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Originally Posted by orangeapeel
I didnt think that Pacesetter had a y-pipe.
I better check on that maybe the shop meant pacesetter LT but some other ORY
Old 07-04-2006, 09:58 PM
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Well no one I can find has this set-up that lives around so that I can hear the difference between catted and without... so If no Rasp= keep the cats then thats what I will do.

thanks,
Shawn
Old 07-04-2006, 10:16 PM
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run cats. all catbacks rasp with an ORY, yes, even the hooker. so why do people say it doesn't rasp? three main reasons:

1.) most people don't know what their car sounds like since they've never heard anyone drive it

2.) some people can tolerate rasp better than others

3.) some people don't even know what rasp is! (it's that BLAT BLAT noise on decel when you rev it high)

a catted y will get rid of the rasp much better than an ORY will. however, even with a catted y, the LS1 is usually not 100% rasp free. it'll just be far better than an ORY.
Old 07-04-2006, 11:12 PM
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Originally Posted by ChocoTaco369
run cats. all catbacks rasp with an ORY, yes, even the hooker.

3.) some people don't even know what rasp is! (it's that BLAT BLAT noise on decel when you rev it high)
Most people consider the high pitched sound that occurs roughly between 2200-2600 rpms on accel rasp. It's generally not used to describe the decel noise, as you don't hear it if you drive properly.

And no, chances are your Hooker won't rasp / will have VERY little rasp as long as you're running a Y pipe with a flowmaster style collector, such as the mufflex. I've had this setup on 2 cars, one that was just boltons/cammed, and one that was heavily modified, both had a clean, deep exhaust note all throughout the powerband. If you run a Y pipe like you're describing, as the one you can buy with pacesetters, or any in which the pipes just run into each other as a collector, you will experience rasp.

Last edited by LSUxBlake; 07-04-2006 at 11:21 PM.
Old 07-04-2006, 11:21 PM
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Originally Posted by LSUxBlake
Most people consider the high pitched sound that occurs roughly between 2200-2600 rpms on accel rasp. It's generally not used to describe the decel noise, as you don't hear it if you drive properly.
Correct.
Old 07-04-2006, 11:24 PM
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I guess I like rasp then lol
Old 07-05-2006, 03:19 AM
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Apparently. I think that you just don't know what part is "rasptastic".
Old 07-05-2006, 06:32 AM
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Originally Posted by ChocoTaco369
3.) some people don't even know what rasp is! (it's that BLAT BLAT noise on decel when you rev it high)

Hope this link works... http://www.ls1sounds.com/Hooker/hook...LT_3in-ORY.wmv

this link is from LS1sounds.com I went to Hooker section, then down towards the bottom where it says " Pacesetter/ORY/Hooker/3"system"

When I watch the video, it sounds good to me until...he stomps it then lets off he does it a few times. So yeah I think that the noise that I dislike/call Rasp is on the way down when he lets off the accel.

That seem right to anyone?

thanks again everyone for helping me out...its tough to make the decision when I can't hear in person
Old 07-05-2006, 07:26 AM
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Originally Posted by LSUxBlake
Most people consider the high pitched sound that occurs roughly between 2200-2600 rpms on accel rasp.
*BLAT BLAT* is rasp. the noise you are describing is more like drone. i know what you're saying, my old V6 did it at 3000 rpm's on the dot. sounds like ****. another reason why i love my dual/dual.
Old 07-05-2006, 10:38 AM
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Originally Posted by ChocoTaco369
*BLAT BLAT* is rasp. the noise you are describing is more like drone. i know what you're saying, my old V6 did it at 3000 rpm's on the dot. sounds like ****. another reason why i love my dual/dual.
Yes, its a splatty sound that occurs in the RPM range I listed. Drone is a totally different animal. Here's a vid clip where I intentionally made the car rasp. It happens in the very first part of the clip when I'm in second gear, you can clearly hear the exhaust rasping during that rpm range while I accel. Granted it's very toned down on this video due to the nature of the exhaust, but it can still be easily heard. It's an 11mb video, so not 56k friendly. Of course the best way to hear rasp is to just watch someone drive away with LT/ORY/Borla.

http://www.lsuxblake.com/Trans%20Am/SLPDD.wmv
Old 07-05-2006, 10:46 AM
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what i'm saying is people usually confuse drone with rasp. that high pitched sound - which sadly is a raspy high pitched squeel, which causes a lot of people to consider it as rasp - that causes interior resonance is just drone. it doesn't have to be long resonance on a highway to be considered drone. even if there is interior resonance for 2 seconds, that's 2 seconds of drone.

rasp is just hard to describe. BLAT BLAT is the general definition of rasp but the best adjective to describe the sound at around 2400rpms with a hooker w/ORY is, well, a raspy drone...

we need to invent other terms...rasp has 2 different definitions
Old 07-05-2006, 11:04 AM
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Magnaflow HF cats cost me 9rwhp @ about equal rwtq back when I was cam only. The slight power loss was well worth it as the sound was great. Even with the Corsa muffler it had no rasp at all after adding the cats at any rpm. The Corsa was pretty raspy in the 2200-2800rpms range with the ORY. I've only ran my current Hooker muffler with cats so I have no experience on the sound with an ORY. Although it would be hard to beat the current way it sounds with H/C LTs Cat Y and CME....
Old 07-05-2006, 11:37 AM
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Originally Posted by Ryan02SS
Magnaflow HF cats cost me 9rwhp @ about equal rwtq back when I was cam only. The slight power loss was well worth it as the sound was great. Even with the Corsa muffler it had no rasp at all after adding the cats at any rpm. The Corsa was pretty raspy in the 2200-2800rpms range with the ORY. I've only ran my current Hooker muffler with cats so I have no experience on the sound with an ORY. Although it would be hard to beat the current way it sounds with H/C LTs Cat Y and CME....

so you like your hooker catback with the LT's and catted Y?
Old 07-05-2006, 11:40 AM
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Originally Posted by Ryan02SS
Magnaflow HF cats cost me 9rwhp @ about equal rwtq back when I was cam only. The slight power loss was well worth it as the sound was great. Even with the Corsa muffler it had no rasp at all after adding the cats at any rpm. The Corsa was pretty raspy in the 2200-2800rpms range with the ORY. I've only ran my current Hooker muffler with cats so I have no experience on the sound with an ORY. Although it would be hard to beat the current way it sounds with H/C LTs Cat Y and CME....
Just wondering if you noticed a difference in the exhaust smell / strength of the fumes when running the HF cats.
Old 07-05-2006, 01:14 PM
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Originally Posted by jlashley2001ss
so you like your hooker catback with the LT's and catted Y?
I love the sound! Very docile at idle with slight chop but really roars at WOT. If I need to get really loud I can always open up the QTEC. I DD my car to work and it's very civil for the power it has.

Just wondering if you noticed a difference in the exhaust smell / strength of the fumes when running the HF cats.

Yes with the HF cats there was a noticeable drop in exhaust smell and fumes. While it was never really bad with the ORY during normal driving the sticker was when I pulled the car into the garage. The fumes were pretty intense.
Old 07-05-2006, 09:08 PM
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Someone give me an example of what he means by BLAT BLAT lol. That video I heard, is that sound that sounds like dry leaves being crinkled rasp?


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