Removing Emissions
Thread Starter
Racer
Joined: Oct 2006
Posts: 269
Likes: 7
Removing Emissions
I have a completely stock 77 L48 that I have not had on the road in 10 years. I plan to spend this winter preparing it for the road in the spring. The first few things I will be doing include installing a Performer Air Gap intake, headers, true duals, and removing emissions. When I am done I want the engine compartment to be as uncluttered as possible.
I there anything emissions related that is required for performance purposes. What vacuum hoses are required other than the ones for brakes and distributor? Any advice that members can share would be appreciated.
I there anything emissions related that is required for performance purposes. What vacuum hoses are required other than the ones for brakes and distributor? Any advice that members can share would be appreciated.
Race Director
Joined: Oct 2000
Posts: 11,891
Likes: 3
From: Kansas City, MO ...I'd like to go fishing and catch a fishstick. That'd be convenient. - Mitch Hedberg
You need the vacuum hoses to run the heater controls and the headlights.
You can remove the smog pump and everything it is connected to, the egr and the cat. You might as well ditch the stock air cleaner in favor of an open element. With the stock hood you might run into clearance problems with an airgap intake though.
Don't know if you have a state inspection or not, but removing any or all of the above is against federal law. With that said, hope you make it onto the road next summer.
You can remove the smog pump and everything it is connected to, the egr and the cat. You might as well ditch the stock air cleaner in favor of an open element. With the stock hood you might run into clearance problems with an airgap intake though.
Don't know if you have a state inspection or not, but removing any or all of the above is against federal law. With that said, hope you make it onto the road next summer.
Melting Slicks
Joined: Jul 2004
Posts: 2,577
Likes: 2
From: Long Island New York
Originally Posted by Ak. M
With the stock hood you might run into clearance problems with an airgap intake though.
I run an Edelbrock Performer 2101 on mine with a Q-Jet and a 14x3" open air cleaner, it is a non-EGR manifold and it fits under the hood with no problem. I don't think you'll see any gain with an Air Gap on your stock L48 over the performer anyway. I stripped my '77 L48 of all the emissions stuff and run headers and true duals with 2-1/2" pipes and it did make a difference over stock. The only thing that I left connected is the Evap canister, it keeps the garage from smelling like gas after you drive it and it doesn't effect performance. I still have my PVC connected as well and a chrome breather on the passenger side valve cover, because you have to let the crankcase breathe. The biggest improvement you'll see however is by getting your timing and carb tuned properly.
Thread Starter
Racer
Joined: Oct 2006
Posts: 269
Likes: 7
Thanks for the feedback. In New York no emissions testing is required on cars more than 25 years old. A mechanic is not allowed to remove emissions equipment. That is why I was looking for info on what is required for operation. I will have to remove it myself. If you show up for an inspection with a 25+ year old car they just do a safety check.
So, if I assume that the intake has been replaced and all emissions equipment has been removed, what vacuum lines will still be connected and where should they be connected? Will I need to make major adjustments to my timing and carburetor?
Thanks
So, if I assume that the intake has been replaced and all emissions equipment has been removed, what vacuum lines will still be connected and where should they be connected? Will I need to make major adjustments to my timing and carburetor?
Thanks
Thread Starter
Racer
Joined: Oct 2006
Posts: 269
Likes: 7
Originally Posted by supervette77
I run an Edelbrock Performer 2101 on mine with a Q-Jet and a 14x3" open air cleaner, it is a non-EGR manifold and it fits under the hood with no problem. I don't think you'll see any gain with an Air Gap on your stock L48 over the performer anyway. I stripped my '77 L48 of all the emissions stuff and run headers and true duals with 2-1/2" pipes and it did make a difference over stock. The only thing that I left connected is the Evap canister, it keeps the garage from smelling like gas after you drive it and it doesn't effect performance. I still have my PVC connected as well and a chrome breather on the passenger side valve cover, because you have to let the crankcase breathe. The biggest improvement you'll see however is by getting your timing and carb tuned properly.When I last drove the car 10 years ago it ran perfectly but it was a dog. I just want it to be more responsive. Maybe put me back in the seat a little and possibly break the tires loose. I also want the engine compartment uncluttered.
Please let me know what adjustments you had to make after removing the emissions equipment and what challenges you encountered during the process. Any advice would be greatly appreciated.
Thanks
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
On my 77, to unclutter the engine compartment, and loose weight, I removed the AC compressor and condensor and hoses. Also removed the heater hoses and plugged manifold and water pump. My car didn't have a smog pump. Definitely keep your PCV system operating. You don't need the EGR.
You need to have your Quadrajet rebuilt/upgraded like Lars has done in the past. You should decide on the cam change early in the process so that all changes will match.
The only vacuum hoses left are for headlights, other than power brakes, vac advance etc.
See my sig for other changes on my car.
You need to have your Quadrajet rebuilt/upgraded like Lars has done in the past. You should decide on the cam change early in the process so that all changes will match.
The only vacuum hoses left are for headlights, other than power brakes, vac advance etc.
See my sig for other changes on my car.
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Pro
Joined: Dec 2005
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From: Vettemod.com For the C3 People
St. Jude Donor '06
Originally Posted by Cali77
MyC3,
If your interested in selling those parts your taking off let me know.
I have a 77 I need to get passed for smog in California.
If your interested in selling those parts your taking off let me know.
I have a 77 I need to get passed for smog in California.
tt
Melting Slicks
Joined: Aug 2002
Posts: 3,334
Likes: 4
From: Midland TX
Originally Posted by 73, Dark Blue 454
I'd keep the PCV stuff,..your engine needs this equipment to purge the crankcase of nasty blow-by gases. With your goals, not sure I'd keep much else.
If you don't have PCV you will probably develop oil leaks all over the place. Doesn't hurt performance - probably helps.
How are you going to register your Vette? Classic / Antique or regular.
It may make a difference.
I registered mine as an Antique and don't have to worry about state insections. Another guy registers his 69 as a regular vehicle and has to get annual inspections. The place he took it said they would not pass it because he had an open air cleaner instead of a closed one and did not have the heat pipe that goes from the exhaust manifold to the air inlet.
We have pictures from the AIM and NCRS judging book that says big blocks never had the heat pipe and some big blocks and all LT1s had open air cleaners. No deal. They didn't even notice he doesn't have the air injector.
