headers/exhaust question
Thread Starter
Drifting
Joined: Feb 2009
Posts: 1,302
Likes: 2
From: colchester CT
headers/exhaust question
I am considering buying a 96 lt1 which has headers, flowmaster cat back and a new programmable chip. I live in CT and I am wondering how/if these mods will effect CT emissions testing. Any one out there that lives in CT and has similar mods and went through CT emissions?The car is in nice shape and the price is right, these mods are a bonus and I would be buying it in Long Island NY so I don't know if NY has similar emissions requirements. The car also has 3.73 gears , not that that would effect emissions. Basically it comes with many of the things that I would want to do to it. Thanks
Thread Starter
Drifting
Joined: Feb 2009
Posts: 1,302
Likes: 2
From: colchester CT
I am also wondering what kind of effect these modifications have on fuel efficiency? Obviously you don't buy a vette for good gas mileage but this will be my daily driver so I am wondering what headers, flowmasters, and gears will do to mpg. The 86 I just sold had stock 2.59 gears, do the 3.73 make it quicker off the line or do you see it more at top end. I am just wondering if this car would not be a good DD, if it's set up more for racing or auto cross. Thanks
Racer
Joined: Nov 2010
Posts: 460
Likes: 1
From: Oliphant Ontario
Not familier with your air testing procedures down there, but here, the gears would effect pollution. Our systems measure at idle and at 30 mph, with your higher gears, your engine will rev higher at 30 mph and produce more pollutants..
That said. Headers and cat back exhaust should cause you no grief at the sniffer and will help fuel mileage a very tiny bit. As long as the cats are in good shape they don't know what's behind them.. The chip, could hurt. No way to know but I suspect it is a very mild mod which should go unnoticed.
Mileage wise, your rear gears will hurt mileage a bit (engine will rev higher at cruise) and will help the car launch off the line.
That said. Headers and cat back exhaust should cause you no grief at the sniffer and will help fuel mileage a very tiny bit. As long as the cats are in good shape they don't know what's behind them.. The chip, could hurt. No way to know but I suspect it is a very mild mod which should go unnoticed.
Mileage wise, your rear gears will hurt mileage a bit (engine will rev higher at cruise) and will help the car launch off the line.
Race Director
Joined: May 2006
Posts: 10,691
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From: Phoenix Arizona
I would assume your emission testing is the same as NYC. YOu didn't say if it still has cats (some of the programable chips can fool the computer to think it still has cats if they have been removed). 96 is the first year for OBD2, and they should just plug in to the computer to test. If you don't have a service engine light on, it should pass. You can have it tested at most auto parts stores. The gas mileage will be a lot worse than the 86, figure 10-15 in town, 20 or so highway. LT1's generally average about 25% worse mileage than a L98, gears will definately make it worse. If it's a factor, perhaps you should keep looking....
Thread Starter
Drifting
Joined: Feb 2009
Posts: 1,302
Likes: 2
From: colchester CT
thanks for the info guys. My 86 got about 16 mpg around town maybe 21 on the highway. I thought the lt1 would be better. I always see guys on here claiming they get 20 plus around town and 27 highway. always seems to be a huge disparity. I'm not going to worry about mpg too much though. Just don't want to buy a car and then not make it through emissions.
Melting Slicks
Joined: Jan 2009
Posts: 3,482
Likes: 196
From: folsom california
I would assume your emission testing is the same as NYC. YOu didn't say if it still has cats (some of the programable chips can fool the computer to think it still has cats if they have been removed). 96 is the first year for OBD2, and they should just plug in to the computer to test. If you don't have a service engine light on, it should pass. You can have it tested at most auto parts stores. The gas mileage will be a lot worse than the 86, figure 10-15 in town, 20 or so highway. LT1's generally average about 25% worse mileage than a L98, gears will definately make it worse. If it's a factor, perhaps you should keep looking....
Unfortunately I have no experience with an automatic and / or 3.73 rear gears; perhaps someone who has run this combo will chime in ?
Thread Starter
Drifting
Joined: Feb 2009
Posts: 1,302
Likes: 2
From: colchester CT
yeah, I was looking forward to better gas mileage with the lt1. I guess it depends on which one I get. This one has some nice mods so we'll see. I'm just getting impatient which will soon lead to impulsive. Hopefully the right car , my car, will come along soon
Race Director
Joined: May 2006
Posts: 10,691
Likes: 71
From: Phoenix Arizona
After writing the 25%, I thought better of it. 20% would be closer. L98 autos generally get over 30mpg. I've had several mid 80's autos that would get 33mpg @ 75mph. My LT1's (with 2:55's) get about 28, the 3:08s about 26.
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I respectfully disagree...the LT series have sequential (timed) fuel injection while the L98's used the earlier batch fire injection..which should give the LT's better gas mileage. Remember it was all about fuel economy and emissions. My 96 with a 6 speed manual and 3.45 rear gears can easily get 28 - 29 mpg at (legal) freeway speeds. But, as they say, "Your mileage may differ".
Unfortunately I have no experience with an automatic and / or 3.73 rear gears; perhaps someone who has run this combo will chime in ?
Unfortunately I have no experience with an automatic and / or 3.73 rear gears; perhaps someone who has run this combo will chime in ?
I have a '96 LT1 auto with 3:07 gears and get 28 miles to the gallon cruisin' at 70 on the highway all day long.
Drifting
Joined: Aug 2009
Posts: 1,971
Likes: 243
I am considering buying a 96 lt1 which has headers, flowmaster cat back and a new programmable chip. I live in CT and I am wondering how/if these mods will effect CT emissions testing. Any one out there that lives in CT and has similar mods and went through CT emissions?The car is in nice shape and the price is right, these mods are a bonus and I would be buying it in Long Island NY so I don't know if NY has similar emissions requirements. The car also has 3.73 gears , not that that would effect emissions. Basically it comes with many of the things that I would want to do to it. Thanks
If it is running well and has cats you're probably fine.
I bought my car out of state too - they are going to nail you on the taxes.
Racer
Joined: Nov 2010
Posts: 460
Likes: 1
From: Oliphant Ontario
However, your car being a 96, in CT, will NOT get the sniffer test. It is OBD II and they will link up to the diagnostic port instead. The only thing I can see harming you would be whatever was done in the tune (the aftermarket chip you refer to). If the tune disabled the rear o2s, turned off the air injection pump, etc. it could possibly fail. Other than the diagnostic port test, they will probably do a visual to ensure it has cats and test the gas cap to ensure it does not leak.
If it is running well and has cats you're probably fine.
I bought my car out of state too - they are going to nail you on the taxes.
If it is running well and has cats you're probably fine.
I bought my car out of state too - they are going to nail you on the taxes.
Drifting
Joined: Aug 2009
Posts: 1,971
Likes: 243
94+ is a flash pcm, no chip replacement. If it has a tune it was reflashed. I'd not worry about it. Take it to emissions, if it fails at least you'll know what caused it to fail and go from there. But if it runs right, has cats and no check engine light I'm betting you are just fine.
Le Mans Master
Joined: Oct 2004
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From: Everett WA
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With the 4 speed auto trans that 96 is not going to get much better gas milage than your older car did and the 373 is going to hurt it as well. My high stall tc really hurts my milage around town where it never locks up and I get around 14 but at a steady 65 I can get 23mpg .... but I am running the stock 3.07 not a 373.
Of course "your milage may differ"
Best of luck to you and let us know what you end up getting .... remember the worst thing you can do .... is fall in love with the first one that you drive.
Of course "your milage may differ"
Best of luck to you and let us know what you end up getting .... remember the worst thing you can do .... is fall in love with the first one that you drive.
