removing the emissions on c3
Thread Starter
Instructor
Joined: Jun 2007
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From: Torquay Devon
removing the emissions on c3
Hi peeps,
Have a 76 stingray and I was wondering if I could safely remove the emission gubbins. If I can remove them I don't know where to start and if I have to plug any pipes removed etc. The car has been in the family for over 25 years and is original apart from de catted s/s exhausts. Coming to you guys as obviously you are brought up on the vettes and know your stuff.
Jamie.
Have a 76 stingray and I was wondering if I could safely remove the emission gubbins. If I can remove them I don't know where to start and if I have to plug any pipes removed etc. The car has been in the family for over 25 years and is original apart from de catted s/s exhausts. Coming to you guys as obviously you are brought up on the vettes and know your stuff.
Jamie.
Tech Contributor
Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
There really isn't a good reason for removing it - the gains from doing so are negligible. You're better off just giving the car a good setup and tuning with a correct carb setup and a good ignition advance curve. Yanking off vacuum hoses isn't going to do anything for you...
Le Mans Master
Joined: Jan 2006
Posts: 9,192
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From: Boca Raton Florida
Thats true unless the vac operated emissions stuff is leaking. Lot of people think that the emissions stuff sucks off a lot of HP, but generally its the detuning required by emissions requirements that makes the motors weak. The only real exception is a clogged Cat, but that too is a failure that when fixed would get you back up to snuff quickly.
Safety Car
Joined: Dec 2004
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From: San Diego CA
Generally the only emissions crap that tend to rob power, besides the detuning, are the cat and AIR pump. The AIR pump is kind of a smaller power killer as it's just an extra belt driven by the crank, but the cat tends to kill exhaust flow so bad that it is the main thing that will give some noticable power gains.
PCV and EGR really don't hurt it much. PCV is a good thing. EGR... I'm not a big fan of as I don't like recirculating my hot exhaust back in to my intake, but the power gains from removing it again are kinda minor. Many aftermarket intakes don't even have a place for EGR, including mine.
PCV and EGR really don't hurt it much. PCV is a good thing. EGR... I'm not a big fan of as I don't like recirculating my hot exhaust back in to my intake, but the power gains from removing it again are kinda minor. Many aftermarket intakes don't even have a place for EGR, including mine.
Thread Starter
Instructor
Joined: Jun 2007
Posts: 126
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From: Torquay Devon
thanks for the info, will leave it alone. Here in the U.K. you very rarely see the c1, c3 or c3. Someone at a u.k. forum suggested I de smog the car and this is why I've come to you guys as obviously you know the motor inside out
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Safety Car
Joined: Dec 2004
Posts: 4,071
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From: San Diego CA
Gotta agree with viperbaron on that part, it definitely cleans up the engine.
Top flight corvette ends up charging me less for labor because all of my emissions stuff is gone. Makes it so they can get to stuff under the hood easier.
Top flight corvette ends up charging me less for labor because all of my emissions stuff is gone. Makes it so they can get to stuff under the hood easier.
Le Mans Master
Joined: Jan 2007
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From: Omaha NE
2025 c3 ('74-'82) of the Year Finalist - Unmodified
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You can be clean & still have your stock '76 engine stuff...........
Instructor
Joined: Jun 2005
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From: Bovingdon Hertfordshire
Are you going to the UK Summer Nats. at Huntingdon Racecourse ?
Are you taking the car?
If the answer is yes to both of these, I'm happy to sort the timing for you while we are there...........
Jeremy.
Le Mans Master
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From: Omaha NE
2025 c3 ('74-'82) of the Year Finalist - Unmodified
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Instructor
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From: Atlas is shrugging KC, MO area
