1975 L48 Engine Originallity ?
Thread Starter
Instructor
Joined: Oct 2010
Posts: 140
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From: Sunshine Coast Queensland Australia
1975 L48 Engine Originallity ?
Can anyone tell me what needs to be done here to make this look as original as possible.
from what i can see it is missing the air cleaner rubber hood seal.
can the seal be fitted to this cleaner, and i am assuming the rocker covers are off an L82.
Plan on removing the A/C compressor and some detailing.
from what i can see it is missing the air cleaner rubber hood seal.
can the seal be fitted to this cleaner, and i am assuming the rocker covers are off an L82.
Plan on removing the A/C compressor and some detailing.
Racer
Joined: Feb 2011
Posts: 257
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yeah, that looks like the same 'dual snorkel' air cleaner base thats on my stock L-48 '74, so a rubber hood seal could go on there to replace the chrome lid(then you would have to get the smaller stock filter top)...and I just have the steel orange painted valve covers...but don't see anything else in that photo jumping out as non-original
Instructor
Joined: Apr 2006
Posts: 121
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You need an open top air cleaner lid. also, can anyone tell me what the orange colored part is that is bolted to the front of the heater core box. You can see it in this photo just above the distributer shield. I am an original owner of a 75 coupe and I have noticed that some cars have this part and some do not.
Drifting
Joined: Oct 2010
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From: Chester Virginia
on my 76
You need an open top air cleaner lid. also, can anyone tell me what the orange colored part is that is bolted to the front of the heater core box. You can see it in this photo just above the distributer shield. I am an original owner of a 75 coupe and I have noticed that some cars have this part and some do not.
lance
Race Director
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yeah, that looks like the same 'dual snorkel' air cleaner base thats on my stock L-48 '74, so a rubber hood seal could go on there to replace the chrome lid(then you would have to get the smaller stock filter top)...and I just have the steel orange painted valve covers...but don't see anything else in that photo jumping out as non-original
Not sure also if this car should have an AIR system or not but believe all L48s did.
Le Mans Master
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From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
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You need an open top air cleaner lid. also, can anyone tell me what the orange colored part is that is bolted to the front of the heater core box. You can see it in this photo just above the distributer shield. I am an original owner of a 75 coupe and I have noticed that some cars have this part and some do not.
Instructor
Joined: Apr 2006
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Race Director
Joined: Oct 2000
Posts: 12,639
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From: Shamong, NJ
It is the base for the 74/75 seatbelt emergency override switch. The switch itself is missing (the black plastic & metal piece with the push button on it, in petes74 pic), only the orange plastic base remains. Starting with the 1974 model year, Federal law required that the belts be buckled on occupied front seats, before a car would start. This was known as the "Starter Interrupt" system. New 1974 GM vehicles came with a 10 page book, explaining how the system operated, and how to use the belts.
The system included an override, in case it failed. The override was mounted in the engine compartment, to prevent drivers from regularly bypassing it. This was the Government's first attempt at a "passive" restraint system.
Almost from the first day it was in use, owners started disabling it. There was also quite a bit of trouble with them malfunctioning. There were so many problems and complaints, the Feds finally gave up on it, and repealed the law effective January 75.
All 74 model year cars, and any car built during the 1974 calender year, came with the starter interrupt, and the bypass switch.
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Team Owner
Joined: Aug 1999
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From: Ontario
It is the base for the 74/75 seatbelt emergency override switch. The switch itself is missing (the black plastic & metal piece with the push button on it, in petes74 pic), only the orange plastic base remains. Starting with the 1974 model year, Federal law required that the belts be buckled on occupied front seats, before a car would start. This was known as the "Starter Interrupt" system. New 1974 GM vehicles came with a 10 page book, explaining how the system operated, and how to use the belts.
The system included an override, in case it failed. The override was mounted in the engine compartment, to prevent drivers from regularly bypassing it. This was the Government's first attempt at a "passive" restraint system.
Almost from the first day it was in use, owners started disabling it. There was also quite a bit of trouble with them malfunctioning. There were so many problems and complaints, the Feds finally gave up on it, and repealed the law effective January 75.
All 74 model year cars, and any car built during the 1974 calender year, came with the starter interrupt, and the bypass switch.
Race Director
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Race Director
Joined: Apr 1999
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From: NM
Take a look here http://www.73spot.com/73%20engine/engl48.htm. This is a 73 L48 but the basic looks are the same.
Drifting
Joined: May 2006
Posts: 1,480
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From: Circleville Ohio
Vader Vette
Mike Wards engine looks almost like my 75 L-48 except for the valve covers .I have my air (smog) stuff off and no air stuff of any kind other than that I even have the bad looking rubber seal on top of the carb.
Drifting
Joined: May 2005
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From: Somers CT
Engine is pulled and on an engine stand, not using it. That seal is glued to the air cleaner, I don't think it can be removed without damaging the rubber.
Race Director
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St. Jude Donor '09-'10-'11
What is your VIN number? They had a production change about mid year and went to the covered air cleaner, but not chrome. The valve covers may also be from the factory as well - sometimes they test fit other components or used them if they ran out.
Thread Starter
Instructor
Joined: Oct 2010
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From: Sunshine Coast Queensland Australia
I think i will keep the valve covers and try and polish them up and replace the air cleaner with a nice chrome open type.
do i need a low mount base?
what aftermarket air cleaners will fit? edelbrock 14" ?
