After nearly 2 days of work (no lift or engine hoist) i finally got my Mac's w/offroad pipes in. I was so excited about hearing them for the first time. I turned it on and althought it wasn't much lounder that before, it had a sound of power. I took off down the road and at about 2500 RPM's this horrable raspy/crackly sound hit in and lasted only till about 3500. It sounded exactly like the trucks around here running straight pipes. It makes my car sound like some old junker and im so frustrated. Not only that, but every time i take off i hear lound clanks and thuds and rattles. When it shifts it thuds and clanks again. I wanted a deep rumble that came alive (i love the video of adam_blkknight on f-bodyhideout, sounds perfect). I dont care how loud it is, if it is deep and powerful sounding. What should i do guys.... i cant stand that crackly/raspy sound ... i will put it back stock if i have to in order to get rid of it. My currend mods were a Flowmaster Catback, LS1 Motorsports lid, K&N, and a home ported and descreened MAF.

 

I haven't read one post about macs that didn't mention rasp, so I am not surprised. There are a few things you can do though. Put in some high flow cats will not sap too much HP and bring down the rasp, or you could go with a bullet muffler in the I pipe.
I got my loudmouth with the bullet, and it has little to no rasp while my friend doesn't have the bullet and has quite a bit of rasp.
Good luck!

 

Welcome to the wonderful world of the LS1 sound. This motor sounds like absolute $hit without cats for a SBC IMHO. I'd definitely put some highflow cats on your headers. They should get rid of most of the rasp(if not all) and give a deeper(cleaner) tone. It will be quieter but sound a LOT better. And everything all just depends upon your exact exhaust set-up. Some cat-backs have a deeper sound that others, headers will always affect sound(good or bad), what kind of cam your using, how your cylinder heads are ported, and the overall size(cubic inches) of your motor, etc... If your looking for the LT1 sound, forget it.

Mike

 

Is there any setup without cats that is not raspy/crackly ? I am considering an x-pipe sort of setup. Does anywhere make x-pipes made specifically for our cars ? There aren't any muffler shops around here that i would trust to "custom fit" something like that.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 99-z-28:
<strong>Is there any setup without cats that is not raspy/crackly ? I am considering an x-pipe sort of setup. Does anywhere make x-pipes made specifically for our cars ? There aren't any muffler shops around here that i would trust to "custom fit" something like that.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Sorry but just about every cat-back or exhaust set-up will rasp some without cats on an LS1(some more than others). At least I haven't heard one yet in person that actually doesn't. Supposedly, the SLP dual/dual is about rasp free with orps, but it is also very quiet.

Dr. Gas sells the X-pipe set-up you need. Just use that with 2.5" piping and some quality bullet mufflers to get rid of the exhaust. This true dual set-up should have no rasp without cats.

Mike

 

LOUD AND OBNOXIOUS JUST THE WAY i LIKE IT!

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by ponykila:
<strong>LOUD AND OBNOXIOUS JUST THE WAY i LIKE IT!</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">YEP!!!! <img border="0" alt="[judgement]" title="" src="graemlins/gr_judge.gif" /> <img border="0" alt="[judgement]" title="" src="graemlins/gr_judge.gif" /> <img border="0" alt="[judgement]" title="" src="graemlins/gr_judge.gif" />

 

i have looked around at Dr Gas's website and was kind of confused as to which one to get.... I would like to do a 3" x-pipe but it seems like a lot of people only have the 2.5" ? Do any of their kits bolt up or am i going to have to get some custom piping done. I am really interested in this sytem. Which dynomax bullets should i get as well... im told they come in many lengths. I want the deepest, most rumbling sound i can get without that annoying raspy crackle im getting now.

 

my duals don't rasp at all, period. i will never build another exhaust system without an x-pipe.

<small>[ September 11, 2002, 04:16 PM: Message edited by: ktm520 ]</small>

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 2000LS1Z28:
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 99-z-28:
<strong>Is there any setup without cats that is not raspy/crackly ? I am considering an x-pipe sort of setup. Does anywhere make x-pipes made specifically for our cars ? There aren't any muffler shops around here that i would trust to "custom fit" something like that.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Sorry but just about every cat-back or exhaust set-up will rasp some without cats on an LS1(some more than others). At least I haven't heard one yet in person that actually doesn't. Supposedly, the SLP dual/dual is about rasp free with orps, but it is also very quiet.

Mike</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">My SLP 2OTL has a little rasp between 2100-2600rpm. When its uncapped I think it sounds like sh*t unless your at WOT... then it sounds bad@ss! <img border="0" alt="[Fluffy]" title="" src="graemlins/fluffy.gif" />

 

hooker catback makes NO rasp. I have heard it on almost every header setup with no cats and never heard any rasp. With my heads/cam setup and FLP long tubes with no cats and the hooker catback, it makes ZERO rasp. Open the cutout and the rasp is there slightly at 2400 rpms or so. Close it and it sounds great. Read some threads about the hooker and rasp, just the quality of the hooker catback is great, and sounds awesome to boot.
-dan

 

I beg to differ, the Hooker does indeed have rasp. Although not as much as the others, it still does. I have the complete Hooker system (Hooker LT, ORY and Cat-Back) plus a Vig3600. Right around the 1-2 shift you can get rasp. It is annoying, but luckily only happens when I take off from a light fairly aggressive. At normal driving or hard acceleration (upto WOT) I don't hear any rasp. Every exhaust without cats has rasp, just where/when/how it happens varies. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

The y-pipe is pretty much what causes rasp so if you go duals or an x-pipe or h-pipe, it shouldn't rasp at all

 

Personally I love the rasp, it sounds crazy!

 

It's the worst thing about these cars (mechanically, anyway) especially with a stickshift. Rasp... crackling and popping between shifts...sounds like a farmtruck.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by MRZ28HO:
<strong>I beg to differ, the Hooker does indeed have rasp. Although not as much as the others, it still does. I have the complete Hooker system (Hooker LT, ORY and Cat-Back) plus a Vig3600. Right around the 1-2 shift you can get rasp. It is annoying, but luckily only happens when I take off from a light fairly aggressive. At normal driving or hard acceleration (upto WOT) I don't hear any rasp. Every exhaust without cats has rasp, just where/when/how it happens varies. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">It could be the design of the headers. You're not the first person I have heard that complained about how they're car sounded with Hooker Longtubes...

If you run an LS1 with wide open exhaust, it will be the worst sounding motor on the planet. You can thank the firing order and aluminum block for that. However there are ways to make the LS1 sound good. High flow cats will definately do the trick, but can be costly. There are good catbacks out there that flow well, and knock out 90-95% of the rasp..

FWIW, I run the raspy Macs myself and with my Hooker catback I get zero rasp. I had the ball flanges cut off and also had a 3 inch y-pipe welded in, which helped a good bit. Most of the rasy sound coming from Macs is in the shitty/small collectors and small y-pipe. The Hooker catback is THE best sounding catback for an LS1 IMHO. I have never heard anything without cats that sounded as clear, clean, and good....

Josh

<small>[ September 13, 2002, 02:36 PM: Message edited by: Damian ]</small>