Stock catback-AM I MAKING A MISTAKE?
Thread Starter
Le Mans Master
Joined: Feb 2007
Posts: 9,290
Likes: 1,523
From: Oviedo Florida
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Stock catback-AM I MAKING A MISTAKE?
Hello friends----I have always thought that I was making the
right decision by keeping my stock catback. I thought that
folks changed them for the sound and only sound.
Now I have read a couple of posts where changing to
a aftermarket catback is picking up power.
Here's my stiuation I have a Vortech supercharger, ARH,
X-pipe, cats, a bunch of bolt-on's on a 346 cu in.
making 520 rwhp/500 tq.
Are other member's making this kind of hp with stock
catback ? Or, are you running aftermarket catback's for
power not sound. Believe me I have enough noise as my
vette sit's now. Do you think I have that much back
preasure that I am choking the motor?
Thanks for taking the time to read this and I will be
interested in your reply.---road pilot
right decision by keeping my stock catback. I thought that
folks changed them for the sound and only sound.
Now I have read a couple of posts where changing to
a aftermarket catback is picking up power.
Here's my stiuation I have a Vortech supercharger, ARH,
X-pipe, cats, a bunch of bolt-on's on a 346 cu in.
making 520 rwhp/500 tq.
Are other member's making this kind of hp with stock
catback ? Or, are you running aftermarket catback's for
power not sound. Believe me I have enough noise as my
vette sit's now. Do you think I have that much back
preasure that I am choking the motor?
Thanks for taking the time to read this and I will be
interested in your reply.---road pilot
Race Director
Joined: Jul 2007
Posts: 11,467
Likes: 8
From: 972 and 405
Most, if not all of the aftermarket catbacks are going to be the same 2.5inch diameter as the stock one. However depending on the routing of the pipes, whether they have mufflers or not etc, you MAY notice some minimal gains. I picked up my B&B bullets for the sound, as the rest of the exhaust is stock... for now.
-Alex
-Alex
Safety Car
Joined: Feb 2006
Posts: 4,541
Likes: 385
From: Fort Worth Texas
I think this is the first time I have ever seen someone with those kinds of mods and stock exhaust. If I could only do 2 things to a Vette, it would be intake and exhaust. I think you are cheating your car. Just my opinion though.
Melting Slicks
Joined: Sep 2006
Posts: 2,728
Likes: 142
From: Iowa
I swapped my exhaust for the sound only. I am absolutely sure there are power gains in swapping it, but whatever gains are there would be so little it's not really worth mentioning.
Yeah, I'm only aware of one aftermarket catback setup that is a full 3" all the way. The LG "Big 3" I believe is completely 3.
Most, if not all of the aftermarket catbacks are going to be the same 2.5inch diameter as the stock one.
Pro
Joined: Nov 2003
Posts: 682
Likes: 8
From: Alexandria VA
On an otherwise stock car one would see little to no gain with a new catback. Given your mods you'd see more, but how much, I don't know. Probably not enough to justify the $$ if the performance gains are all you're looking for. But combined with the much better sound and more aggressive look of the pipes coming out the back I think its worth it.
You might want to ask this question over in the FI section. I know those guys have tried a lot of different setups, from stock to straight pipes, to see the gains.
You might want to ask this question over in the FI section. I know those guys have tried a lot of different setups, from stock to straight pipes, to see the gains.
Melting Slicks
Joined: Feb 2006
Posts: 3,191
Likes: 43
From: Scottsdale Az
Hello friends----I have always thought that I was making the
right decision by keeping my stock catback. I thought that
folks changed them for the sound and only sound.
Now I have read a couple of posts where changing to
a aftermarket catback is picking up power.
Here's my stiuation I have a Vortech supercharger, ARH,
X-pipe, cats, a bunch of bolt-on's on a 346 cu in.
making 520 rwhp/500 tq.
Are other member's making this kind of hp with stock
catback ? Or, are you running aftermarket catback's for
power not sound. Believe me I have enough noise as my
vette sit's now. Do you think I have that much back
preasure that I am choking the motor?
Thanks for taking the time to read this and I will be
interested in your reply.---road pilot
right decision by keeping my stock catback. I thought that
folks changed them for the sound and only sound.
Now I have read a couple of posts where changing to
a aftermarket catback is picking up power.
Here's my stiuation I have a Vortech supercharger, ARH,
X-pipe, cats, a bunch of bolt-on's on a 346 cu in.
making 520 rwhp/500 tq.
Are other member's making this kind of hp with stock
catback ? Or, are you running aftermarket catback's for
power not sound. Believe me I have enough noise as my
vette sit's now. Do you think I have that much back
preasure that I am choking the motor?
Thanks for taking the time to read this and I will be
interested in your reply.---road pilot
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Racer
Joined: Mar 2007
Posts: 313
Likes: 0
exhaust
Correct me if I am wrong but the stock Cat back is not a true 2.5 inch exhaust. I know the pipe is 2.5 for the Z06 but it tapers down right where it goes into the muffler to like 2.25 or so. Im happy with my LG big 3. I had some issues with the clamps not holding initially but I ended up getting a couple tack welds for extra insurance. The sound is nice. Not too loud and not too quiet.
Instructor
Joined: Oct 2008
Posts: 137
Likes: 1
From: Wisconsin
Why do I like CORSA??? Because most of their product info. doesn't claim such and such HP gains, but WILL tell you how much more airflow you'll recieve after the install. My Corsa PaceCar flows 47% better than stock...and sound, wow don't even get me started.
Racer
Joined: Dec 2008
Posts: 365
Likes: 0
From: Port Richey FL
IMO its about economics really.
Cat-backs alone are for looks and sound.
Price out a complete 1 7/8 LT header system w/ 3 inch collectors, cats, crossover, and cat back, which for your application I would go with the 3 inch set up from LG then figure 25-30 additional horses then make your decision.
Factor in looks and sound if that is what you are after too then decide.
You are making great power, up to you to decide if you want more and at what cost.
Consider buying a used cat-back and keep your old and try it out. If you don't like it, go back to stock.
Good Luck
Cat-backs alone are for looks and sound.
Price out a complete 1 7/8 LT header system w/ 3 inch collectors, cats, crossover, and cat back, which for your application I would go with the 3 inch set up from LG then figure 25-30 additional horses then make your decision.
Factor in looks and sound if that is what you are after too then decide.
You are making great power, up to you to decide if you want more and at what cost.
Consider buying a used cat-back and keep your old and try it out. If you don't like it, go back to stock.
Good Luck
Le Mans Master
Joined: Sep 2007
Posts: 7,604
Likes: 8
From: Belleville Il
Cat backs DO flow a bit better,,but as stated it's not much. When the advertise 10 to 15 horses you can bet they are stretching the truth as far as possible. IMO with your set up you SHOULD be able to better the advertised numbers by a little bit,,and look and sound a little better. If you want to keep the sound under control,,look into Corsa,,pace car or touring!!