i failed emissions...help me pass
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Member
Joined: Apr 2001
Posts: 341
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From: Kingston, NH
Car: 2004 Wrangler Rubicon
Engine: 4.0
Transmission: NV3550
Axle/Gears: Dana 44s with 4.10 and air lockers
i failed emissions...help me pass
i went to go get a sticker today, and i sorta failed emissions. these are my results (GPM):
HC: mine was 4.71, limit is 2.00
CO: mine was 44.61, limit is 30.00
NOx: mine was 1.44, limit is 3.00
CO2 was 403.58
85 Trans Am with T5. the engine is a 350 with around 350 miles on it, i just rebuilt it. weiand stealth intake, comp cams hi energy 268, holley 600 cfm double pumper. dynomax shorty headers, gutted cat, flowmaster. how much difference would a high flow cat make? anyone know where to find a 2.5" inlet 3" out? any way to check what air/fuel ratio i have by looking at that stuff? please help me make my baby somewhat legal.
ps-you gotta love inspection guys who look under the hood, notice the complete lack of emissions bs whatsoever, and tell me to fiddle with my holley and bring it back
HC: mine was 4.71, limit is 2.00
CO: mine was 44.61, limit is 30.00
NOx: mine was 1.44, limit is 3.00
CO2 was 403.58
85 Trans Am with T5. the engine is a 350 with around 350 miles on it, i just rebuilt it. weiand stealth intake, comp cams hi energy 268, holley 600 cfm double pumper. dynomax shorty headers, gutted cat, flowmaster. how much difference would a high flow cat make? anyone know where to find a 2.5" inlet 3" out? any way to check what air/fuel ratio i have by looking at that stuff? please help me make my baby somewhat legal.
ps-you gotta love inspection guys who look under the hood, notice the complete lack of emissions bs whatsoever, and tell me to fiddle with my holley and bring it back
Senior Member
Joined: Oct 2001
Posts: 674
Likes: 2
From: Stevens Point Wisconsin
Car: 1991 Formula
Engine: 350 firebreathing inches of Small Block Chevrolet
Transmission: A 700R4 that has trouble handling the formentioned 350.
Dude if the inspector knew that you didn't have the emmisions stuff on it? Just buy him a 12-pack of Miller and go back split it with him and "Boom " like magic you passed.
.
Well it worked for a friend of mine in Virginia.
Later, Garrett
.Well it worked for a friend of mine in Virginia.
Later, Garrett
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Joined: Jan 2000
Posts: 19,651
Likes: 309
87,
By the numbers alone, it appears that you're running a little fat (rich). The relatively low NOx and high HC/CO indicates incomplete combustion and low combustion temperatures.
Lean the mix, get the engien hot for testing, and cross your fingers. A cat would certainly help.
By the numbers alone, it appears that you're running a little fat (rich). The relatively low NOx and high HC/CO indicates incomplete combustion and low combustion temperatures.
Lean the mix, get the engien hot for testing, and cross your fingers. A cat would certainly help.
Supreme Member
Joined: Jul 1999
Posts: 18,457
Likes: 16
From: Loveland, OH, US
Car: 4
Engine: 6
Transmission: 5
A cat would definitely cure it. Your numbers look to me like a low-compression engine that's set up more to where it runs the best, with little or no compromise for emissions.
You could try dinking with the carb, but it may take several tries through the line before you get it right, and even then I wouldn't bet on it making it.
With a 2½" inlet to the cat (leftover LG4 stuff obviously) a high flow cat is not going to make the slightest difference to how the engine runs, it's already strangled in a big way. Just get a 3" one and have your local muffler shop use an adapter. Or better yet, look on the bright side, and take advantage of the opportunity to get rid of all that LG4 stuff, and claim your extra power you've left on the table by leaving that drinking straw on there.
I wish I lived in a place where the numbers were that high...
You could try dinking with the carb, but it may take several tries through the line before you get it right, and even then I wouldn't bet on it making it.
With a 2½" inlet to the cat (leftover LG4 stuff obviously) a high flow cat is not going to make the slightest difference to how the engine runs, it's already strangled in a big way. Just get a 3" one and have your local muffler shop use an adapter. Or better yet, look on the bright side, and take advantage of the opportunity to get rid of all that LG4 stuff, and claim your extra power you've left on the table by leaving that drinking straw on there.
I wish I lived in a place where the numbers were that high...
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