I'm thinking about cutting off the tips of an aftermarket catback and welding some stock z/28 tips on for the stock look. I don't want to use the full stock catback because it's 2.75" and restrictive so I figured buying a cheap used 3" catback and welding some stock tips would give me better performance and sound.Has anyone done this?

 

Get an electric cutout and keep the stock exhaust if you really want a stock look. You'll gain a few hp over an aftermarket catback too. You'll save $$$ too.

 

Well I considered that but electric cutouts are $160 and that doesnt count installation and wiring. I'll be selling my Borla when I do this so I just want to make money or break even on the deal.

 

Also, I've heard people having problems w/ electric cutouts.

 

The stock exhaust pipes are not restrictive.
It's the muffler that is restrictive.
The .25" larger pipe means nothing to a mild/moderately modded LS1.
The stock pipes are mandrel bent stainless, get a muffler with the sound you like and use the rest of the stock stuff. You'll spend alot less for the same gains.
Good luck
Dave

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by ratio411:
<strong> The stock exhaust pipes are not restrictive.
It's the muffler that is restrictive.
The .25" larger pipe means nothing to a mild/moderately modded LS1.
The stock pipes are mandrel bent stainless, get a muffler with the sound you like and use the rest of the stock stuff. You'll spend alot less for the same gains.
Good luck
Dave </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">That is what I said at first but people then told me the piping itself was restrictive. So confused <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />

 

According to everything I've read on catcacks on average you'll gain around 15 rwhp with a full catback and about 10 with just the muffler. Somebody on LS1.com with a Magnaflow catback and a cutout only gain one more hp with the cutout open over the Magnaflow catback. Just replace the muffler for $100 instead of $400-700 for a catback since you want to keep the stock tips. Another idea is Fast toys sells chromed stock looking tips.

 

http://www.exhaustproslinc.com
they have just the magnaflow muffler <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> . Throw a cut out on too just in case you wanna get buck-wild!!

 

Ok, what do the muffler dimensions have to be to replace the stock muffler?

 

Not to beat a dead horse, but what about a regular cutout? You can get one for $50 installed. Can't beat that.

What about a bullet in place of the stock muffler?

 

I'll say it again. You get as much power from a muffler as a cat-back.
I have a muffler with the stock 2.75" piping and pulled as much on the dyno as guys with the most expensive cat-backs... same day, same dyno, same mods other than pipe size.

As for cut-outs and !muffler exhaust, they are the cheapest way to go, but they sound like *** IMO. Way too much rasp, not enough deep bass.
My .02
Dave

 

Ok I have long tubes, off road pipe, and a bullet in the i-pipe already. I'm going to go with the stock catback but replace the muffler on it. I don't want a cutout because I don't want to have to uncap it if I wanna run someone and I don't wanna spend $170 for an electric one. I'm selling my Borla to go back to stock because Borla sounds like *** w/ headers and orp.

I've pretty much decided on a Magnaflow for the replacement muffler because I'm going for the sleeper look and I want it to be tame when cruising.

But can anyone tell me which mufflers directly replace the stock muffler? Isn't the stock muffler 1 in and 2 out?

 

A bullet is under $40... How is that overpriced?
Your exhaust sound is modified by the cats anyway. If you really believe that you should have pure and natural exhaust, you aren't even close until you rid the cats.
I posted my opinion and stand by it.
Dave

 

Internally stock, the stock exhaust system isn't much of a restriction. I have an electric cuttout, full bolt-ons including headers with no cats, and the stock exhaust system running 113.3 MPH in the 1/4 through the cuttout. With the cuttout closed I lose a half MPH.