Emissions compliance question

[VSTNG]

During the process of discussing going true dual exhaust on my '07 V6, the person at the performance shop I was speaking with asked if I wanted to keep the catalytic converters in the final configuration. I was surprised by the question. I didn't know it could even be considered. He said they do not look. He said, if the emissions levels pass, then they pass. Should I be worried about "tampering" consequences? I live in Maricopa county, and drive this car every day. I don't have an option regarding annual emissions testing.

[Torchmach]

It is a Federal Offense to remove Catalytic Converters from a Vehicle that came from the Manufacture with them, there are ways around this though.

You could say you Car is "for offroad use only", remove the license plate, and send it to the shop on a flatbed truck. The shop owner then would not be legally liable for removing the Cats. Your Cats could have been "accidentally damaged on a traffic bump", in which case you are legally allowed to replace them with highflow aftermarket Cats.

The Shop owner is a business man who wants to operate within the laws (ie, no fines or jail), and still keep his customer happy.

IMO go with highflo Cats. they don't add that much backpressure, which BTW, aids lowend torque/bottomend performace, and you are legal. We all have to breath the same air too, and it is bad enough around here during the winter. Just use care around traffic bumps after you install them, woundn't want to have to replace those Cats again!

[Jacostang]

Well I would check and see what exactly happens to the system before you do that. The news cars all they do for emissions is plug the car in and checks the system, if by taking the cats off this trgggers a check engine light it will fail automatically. The they start checking all over your car!!!!

[VSTNG]

Thank you for that advice. Now I need opinions on the quoted price. From the cats back, replace everything (single manufacturer's '07 V6 exhaust) with the following: dual Magnaflow mufflers, dual resonators, 2 chrome tips. All joints welded. All labor and parts $650 at a Tempe performance shop. Seem right?

[BurnTire]

Thank you for that advice. Now I need opinions on the quoted price. From the cats back, replace everything (single manufacturer's '07 V6 exhaust) with the following: dual Magnaflow mufflers, dual resonators, 2 chrome tips. All joints welded. All labor and parts $650 at a Tempe performance shop. Seem right?

Sounds Resonable.

[Indy]

You may not want all the joints welded, it could cause problems in the future if you need to remove the tranny. Just a thought take it for what its worth.

[VSTNG]

OK ... and from my discussion with the performance shop, there's been no mention of an X pipe or an H pipe in this configuration. Should I be asking for that too or best left completely separate? Yes, I'm a newbie to all of this.

[BurnTire]

OK ... and from my discussion with the performance shop, there's been no mention of an X pipe or an H pipe in this configuration. Should I be asking for that too or best left completely separate? Yes, I'm a newbie to all of this.

I would recommend keeping the catalytic converters and doing the mufflers if you want a better sound.

What does the stock setup consist of?

I am not familiar with the V-6, but I believe that you have a single muffler.

What is your mid pipe like?

Does the exhaust come out of the manifolds and then merge in to 1 pipe the whole way back to the muffler?

An X or H is a true dual setup form front to back.

As far as the cats I would keep them. It will burn cleaner. Without cats you will get more fumes.

[VSTNG]

Stock '07 V6 config. is as follows: 2 headers, one each off of each side of the V6, followed by a catalytic converter on each side, then the two sides connect via a Y pipe, with a single pipe going all the way back to the single stock muffler. My question is about staying separate from headers to the 2 new mufflers or if there is a benefit to adding an x or h mid pipe between the stock catalytic converters and the 2 new Magnaflow mufflers?

[BurnTire]

Stock '07 V6 config. is as follows: 2 headers, one each off of each side of the V6, followed by a catalytic converter on each side, then the two sides connect via a Y pipe, with a single pipe going all the way back to the single stock muffler. My question is about staying separate from headers to the 2 new mufflers or if there is a benefit to adding an x or h mid pipe between the stock catalytic converters and the 2 new Magnaflow mufflers?

What is the shop planning to do in the quote you received?

This is from the flowmaster web site.

Will my late model vehicle run better if I replace the single inlet muffler with a true dual exhaust system?
Flowmaster does not recommend replacing factory single inlet exhaust systems with a "true dual" system on computer controlled vehicles. The computers in most late model vehicles will not be able to compensate with the fuel needed with an almost doubling of the exhaust flow. Flowmasters dual outlet kits will give you the look of a "true dual" system, while optimizing the vehicles performance.

Do I need to install an "H" pipe to my dual exhaust?
Flowmaster strongly recommends using an "H" pipe, commonly known as a "balance tube" on all "true dual" exhaust systems. An "H" pipe equalizes the pressures between both banks of the engine giving a broader and flatter torque curve throughout the rpm range. It also eliminates "back-rap" common on deceleration, and creates a deeper mellower tone both inside and outside of the vehicle.
Is an "X" pipe better than and "H" pipe?
Over the years, Flowmaster's testing of all types of crossovers, including "X pipes", has revealed no substantial benefits over a properly installed "H" pipe on street driven applications. However, in race applications with small cubic inch engines and /or restricted (small bore) carburetors, will respond well to the addition of X pipes, tri-y styled collectors and/or properly designed single exhaust systems.