This setup will be better than stock. However smog inspections would be a problem, and you should get a H/X pipe put in.
Wondering about this exaust setup
Thread Starter
Racer
Joined: Sep 2008
Posts: 273
Likes: 0
From: Tallahassee Florida
Wondering about this exaust setup
I found these pipes for cheap and wondering what you guys thought of the pipes... How come the pipes arn't for highway use and will they sound good?.. I was thinking about adding chambered muffler eliminatorshttp://www.mamotorworks.com/corvette-1984+91-dual-exhuast-1-36-928.html
Safety Car
Joined: Dec 2006
Posts: 4,290
Likes: 6
From: St Marys GA
looks like a substantial upgrade over stock; your stock system necks down to a single pipe throught the cat, then breaks back into 2. This system stays true dual, which will definitely help performance.
However, it looks like it completely eliminates the cats, which is why they say you can't use it on the highway. I'm not familiar with your state's inspection rules, but your car may not pass inspection with these.
Also, there's no H or X-pipe in the system. It would probably be a good idea to have the exhaust shop install one of these; it will greatly help both performance and eliminate drone.
However, it looks like it completely eliminates the cats, which is why they say you can't use it on the highway. I'm not familiar with your state's inspection rules, but your car may not pass inspection with these.
Also, there's no H or X-pipe in the system. It would probably be a good idea to have the exhaust shop install one of these; it will greatly help both performance and eliminate drone.
Pro
Joined: Jan 2008
Posts: 584
Likes: 1
From: Near Lockport NY Black 1986 Coupe
If you weld a set of small bullet cats where the stock pre-cats would be, it would be possible to pass inspection and still gain a plausible 10-15rwhp over stock.
I do agree with the others that it needs an H-pipe, but even without you would gain a bit more without the bottlenecks of the stock system. And the system is 2.25" to boot, which will sustain your low-end grunt. I'd do it.
I do agree with the others that it needs an H-pipe, but even without you would gain a bit more without the bottlenecks of the stock system. And the system is 2.25" to boot, which will sustain your low-end grunt. I'd do it.
Race Director
Joined: Nov 2003
Posts: 12,221
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
They will be louder than your stock system by a potentially large margin -- if you don't re-install mufflers and/or both cats (front/main).
Essentially, you'll have 3 levels of louder as you eliminate each of the stock exhaust components. Having 2 of 3 will sound sporty. Every passenger will probably like the sound. If you remove 2 or more components, you will find people (including possibly yourself) that will find the result too loud/resonating.
3 components = 1) front cats 2)main cat 3) mufflers
Race Director
Joined: Jun 2004
Posts: 13,949
Likes: 705
From: WI
There are some better made systems, that come with X or H pipes. Check these:
http://www.pypesexhaust.com/gallery109.html
http://www.allencorvetteexhaustsystems.com/
I had a local place make mine, no shipping cost that way.
http://www.pypesexhaust.com/gallery109.html
http://www.allencorvetteexhaustsystems.com/
I had a local place make mine, no shipping cost that way.
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Team Owner
Joined: Dec 1999
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The chambered system is supposed to sound like the mid-sixties Vettes with the factory side exhaust. They arent too loud at lower RPM's, but at WOT, they will be LOUD. IIRC, Walker made a number of these systems for differerent cars. A friend had them on an 86 V8 Mustang that he used for SCCA Rallye and the car was outrageously loud at full throttle. It could draw attention from those pesky cars with the blue lights on top....
Also, if your car currently has the stock exhaust, you may find that most muffler shops will not remove your cats and install this system. It's a violation of federal law to remove cats and the fine (if a shop gets caught) can run into 5 figures.
You could remove the existing system yourself and get a shop to do the install if you don't want to do all of it yourself, but call around to find a shop that will do that for you.
You also need to verify that the system comes with an O2 bung so you can reinstall the O2 sensor. Not a big deal if it doesn't; any muffler shop can weld in a new bung. Might want to buy a new O2 sensor if the one in the car is original.
Also, if your car currently has the stock exhaust, you may find that most muffler shops will not remove your cats and install this system. It's a violation of federal law to remove cats and the fine (if a shop gets caught) can run into 5 figures.
You could remove the existing system yourself and get a shop to do the install if you don't want to do all of it yourself, but call around to find a shop that will do that for you.
You also need to verify that the system comes with an O2 bung so you can reinstall the O2 sensor. Not a big deal if it doesn't; any muffler shop can weld in a new bung. Might want to buy a new O2 sensor if the one in the car is original.
Instructor
Joined: Sep 2008
Posts: 222
Likes: 0
From: Lafayette Indiana
There are some better made systems, that come with X or H pipes. Check these:
http://www.allencorvetteexhaustsystems.com/
I had a local place make mine, no shipping cost that way.
http://www.allencorvetteexhaustsystems.com/
I had a local place make mine, no shipping cost that way.
I had no idea they existed....gonna have to check them out. Thanks for the link
Instructor
Joined: Mar 2007
Posts: 233
Likes: 0
From: Red Oak Texas
my question is, where the middle cat is located at, there is a pipe that runs to it going back up the motor. What do you do with this pipe since you will be getting rid of the middle cat??? Will it throw a check engine light?
Race Director
Joined: Nov 2003
Posts: 12,221
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
That's the air tube coming from the air pump. It won't throw a code if not used. It just spits out air. Either tie it off and forget it. Or remove AIR system and install AIR delete pulley.
Safety Car
Joined: Jan 2004
Posts: 3,783
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From: Northern California
Last edited by GKK; Nov 18, 2008 at 02:04 PM.
Thread Starter
Racer
Joined: Sep 2008
Posts: 273
Likes: 0
From: Tallahassee Florida
When u talk about putting at least one of two cats back onto this exaust system, won't the cat restrict airflow? I was planning on putting the dual pipes along with perfromance mufflers. Won't that sound pretty good? Also, what is the biggest size pipes I connect to the stock manifold?