C3 "gill" differences
Melting Slicks
Joined: Jul 2010
Posts: 3,176
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From: perth western australia
From the factory all the 68 and 69 had the fourth gill blocked off . I think it was because the fourth opened into the plenum area and would allow engine room air that vented from the front three to go into the cabin vent . Your picture probably shows the green painted car with all four areas blacked out and the blanked off area "disappears " into the black paint. , the orange car has just had the blanked part done in body colour .
Team Owner
Joined: Jan 2006
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From: Crossville TN
Correct. The 4th gill 'appeared' to be open, but it was only because that 'opening' was painted semi-flat black from the factory. I believe that there were only 3 gills open on '68 & '69 cars....unless and owner chose to cut on the car.
Last edited by 7T1vette; May 23, 2021 at 12:40 AM.
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From: New Or-leens Loo-z-anna
(It really is a '68....mostly).
Just another Corvette guy
Joined: Feb 1999
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From: Palm Springs, CA.
Many either forget or just don't know to paint the fourth slot semi gloss black after the car has been repainted.
Looks pretty bad when it's body color, especially a lighter body color.
Looks pretty bad when it's body color, especially a lighter body color.
Thread Starter
Pro
Joined: Mar 2014
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From: bumpy roads NJ
haha. Just asking because I didn't know if I was supposed to cut the 4th slot out or what --
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Larry
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From: Virginia USA
I don't know if it's blocked off or its made that way because of the ventilation system. On my 71 you can take off the egg crate gills and that area is not open at all. Does 68-69 have Astro-ventilation? The area where the 4th gill if it were on a 71 it would be part of the Astro ventilation air box.
Last edited by theandies; May 24, 2021 at 08:38 AM.
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From: New Or-leens Loo-z-anna
I don't know if it's blocked off or its made that way because of the ventilation system. On my 71 you can take off the egg crate gills and that area is not open at all. Does 68-69 have Astro-ventilation? The area where the 4th gill if it were on a 71 it would be part of the Astro ventilation air box.
Yep...Astro ventilation.......manually operated vent in each kick panel to keep the shoes cool and provide air circulation down low. There is a "snorkel" at the top of each airbox that allows "cool air" to enter the vent system. I taped the snorkels closed to keep sanding dust away from the airboxes.
Squirrels had stored a gallon of acorns at the bottom of each vent box. When I first removed the kickpanel and managed to open the vent acorns rolled onto the floorboard.
Last edited by doorgunner; May 24, 2021 at 01:36 PM.
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