TRUE DUAL OPTIONS - K1500 with Manual Trans

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volfan72

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Good luck with that. They're risking a ten-thousand dollar federal (not state, not local) fine for screwing with your catalytic converters.
I have no idea what you are referring too, please explain with specific details.

I have had multiple exhausts built which included replacing OEM converters with hi flowing converters while still maintaining the integrity of my counties emissions testing.

The purpose of this thread was to discover how GMT 400 owners specifically 4 Wheel drive versions created “True Dual” setups from the manifold/collector back.

What was your goal in responding?
 

volfan72

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It’s not cheating if your exhaust maintains the requirements set forth by your county or state’s government emissions testing.

These are the types of responses that make finding useful information within this forum so challenging.

Does this forum even have a moderator?
 

OutlawDrifter

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You've never really given us a clear indication of your setup at the engine. Long tubes vs stock manifolds/shorty headers would call for different options.

What is your goal for running true dual exhaust? Looks, sound, more power? A single 3" exhaust will flow far more HP than any of these pickups could produce from the factory.
 

thegawd

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I think there is only an assumption that you would be removing the catalytic converters.... your honestly the first person I have heard of on here who is keeping them while building your dual exhaust.

I wish more people cared about clean air and kept their cats.

theres so many posts where people are like I cut my cats off, threw the vapour canister and egr in the garbage, tuned out O2 sensors, put a carb on and now I smell raw fuel and my truck is running like shìt..... well put it back together....

I think if people are going to keep the Cats which isn't only legal but morally right, let us know just to avoid the confusion with the others...

and Thanks Man!

CHEERS!
 

volfan72

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You've never really given us a clear indication of your setup at the engine. Long tubes vs stock manifolds/shorty headers would call for different options.

What is your goal for running true dual exhaust? Looks, sound, more power? A single 3" exhaust will flow far more HP than any of these pickups could produce from the factory.
Well said. My apologies. I was just wanting to see options regarding crossing over from drivers manifold/collector without using a Y Pipe for a “True Dual” setup.

My engine dynoed 448 at the crank naturally aspirated.
 
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HeavyAsAChevy

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Well said. My apologies. I was just wanting to see options regarding crossing over from drivers manifold/collector without using a Y Pipe for a “True Dual” setup.

My engine dynoed 458 at the crank naturally aspirated.
Any pics???
 

volfan72

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All finished. My OCD would have preferred the drivers Convertor parallel with the motor. However, there was not enough room with the bends required. Definitely flows better now and actually smoother at low RPMs.

BEFORE = 2 1/4” Y Pipe with single 3” large with Magnaflow muffler all the way back.

AFTER = 2 1/2” from collector back with X Pipe and 2 Magnaflow mufflers.
 

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Schurkey

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US Federal law requires you to keep the same number of catalytic converters, in the same location as stock--unless you've got an exemption number from the EPA, or from the California Air Resources Board (CARB). Canada generally follows US Federal emissions laws, but there may be differences I'm not aware of.

If your vehicle was made with one catalyst, you can't install two.

If your vehicle was made with two catalysts on the passenger side, you can't move one to the driver's side, or sneak it in under the transmission.

You cannot remove a FUNCTIONING OEM catalytic converter even if you install an aftermarket "high performance" catalyst in it's place.

It is legal to remove a non-functioning OEM catalyst in order to install an aftermarket "universal" catalyst...but not in California.

Screwing with the EPA is a FEDERAL offense--the Feds can (but usually don't) bust you anywhere in the USA. Point is, if they want you...you've given them a way to get you.

CARB, of course is applicable only in California, and other states that have adopted Crazy California emissions requirements, so those states may require CARB exemptions, or perhaps they have their own emissions-compliance officers. Emissions regulations can be more strict than EPA, but never LESS strict. Under CARB, "universal" catalysts are likely illegal--you have to have "OEM-quality" catalysts which may or may not be made/sold by the vehicle manufacturer, but they're about three+ times as expensive as the "universal" cats legal in the other states.

A business faces serious fines for violating EPA regulations. An individual so far as I know doesn't face massive fines for DIY violation of the EPA regulations, but the vehicle registration can be revoked unless it's "repaired". Again, enforcement is sparse and inconsistent, but it can exist.

BE AWARE of what the Government can do to you when you make them unhappy.
 
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