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I just picked up a Z28 hood for my son's 91' RS. The seller claimed it was a factory hood but I don't remember ever hearing about fiberglass hoods coming stock from the factory. The hood is currently in primer over some crappy red paint. Maybe there's some OEM quality paint hiding under all that but I'm not seeing it if there is. Can anyone help me out with this ? This hood also has functional scoops, the doors at the end of the scoops open & there's a gasket setup on the underside that will mate up to an air cleaner for a ram-air sorta thing. Anyone know what year(s) this thing might have come off & where I can score the rest of the air cleaner assembly I'll need (the car is a 305 TPI) ? Also what's the deal with the functional scoop doors ? Do I use something like an old push/pull choke cable to actuate them or is there supposed to be some other sort of setup to open/close them ? If it *isn't* an OEM hood then does anyone know who might make/sell these (if they still do) since maybe they'd have a line on the air cleaner assembly as well as what we'll need to operate the scoop doors.
Also, the top skin is just starting to separate from the bottom half of the hood on the passenger side up near the windshield. While this doesn't look like a difficult fix (I figured some resin & a bit of fiberglass reinforcement will be the way to go) I'm wondering about long term durability with the hood hinges. We're already using hood pins & I had planned on keeping them when swapping over from the original steel hood to this new fiberglass hood but I'm thinking that it might be a good idea to remove the lift pistons on the hinges. I'm concerned that he'll damage the hood over time trying to close it against the resistance of the pistons & removing them & using some sort of prop rod would be the way to go. What are the rest of y'all doing with your fiberglass/CF hoods & the lift pistons ?
Any help or insights here will be appreciated, thanks.
82-83 z28 came with that hood and i think the functional scoops only came on the crossfire?? someone chime in? thats what the gasket is for around the scoop
and the factory had weaker pistons on the glass hoods
Ok, Thanx. That would make sense because the guy I bought it from offered me a crossfire setup complete with computer. The gasket on the bottom of the hood is oval shaped rather than circular as you'd expect with a carb or single throttle body TPI which seems like it would match up well with that photo of the crossfire air filter housing (at least I'm assuming that's what the photo was of).
Any ideas how the scoop doors are supposed to actuate ? I was thinking of using a push/pull choke cable to open & close them but that's an admittedly hokey solution. If there's a better way I'd like to look into it. Anyone know what the OEM setup was like ?
those hoods with functional air scoop are found on 1982
-83 z28 with CFI,the flaps were opened by a solenoid
activated by the ECM above a certain throttle opening.
carbed '82 z28s have the same hood,only without the
cold air flaps.Carbed '83 z28s are supposed to have
steel hoods,but some L69(5.0 H.O) with "fiberglass"
hood have been reported.The hood is also known as the
"SMC"(sheet molded compound)hood as that is what
the hood is made of-instead of polyester resin mixed
with glass strands like fiberglass,SMC is more like
epoxy resin mixed with glass(you can buy SMC repair
kits,works better than fiberglass repair kits to repair
SMC panels) SMC hoods have the gas strut hinges
while steel hoods i have seen have the clockspring
hinges.The struts only seem to last 7-10yrs,so i have
a prop rod for mine
It's fairly common for the hoods to start seperating over time. I had one that at speed, the back corners would start comming up. I was going to fix it with some fiberglass resin, but found one in better shape and used it instead.
Quote:
Originally Posted by 8t2 z-chev
those hoods with functional air scoop are found on 1982
-83 z28 with CFI,the flaps were opened by a solenoid
activated by the ECM above a certain throttle opening.
carbed '82 z28s have the same hood,only without the
cold air flaps.Carbed '83 z28s are supposed to have steel hoods,but some L69(5.0 H.O) with "fiberglass" hood have been reported.The hood is also known as the
"SMC"(sheet molded compound)hood as that is what
the hood is made of-instead of polyester resin mixed
with glass strands like fiberglass,SMC is more like
epoxy resin mixed with glass(you can buy SMC repair
kits,works better than fiberglass repair kits to repair
SMC panels) SMC hoods have the gas strut hinges
while steel hoods i have seen have the clockspring
hinges.The struts only seem to last 7-10yrs,so i have
a prop rod for mine
My 83 Z28 (non Crossfire) has a SMC hood. It was the same color (original paint when I got it) as the rest of the car, so I'll assume it was origianal to the car.
Got one of those SMC hood on mine, they came on 82-84 camaros, mine isn't functional, but i would asume that they are vacuum actuated or electrically acuated by a switch on the gas pedal. either way they are made to open at full throttle or close to it, you maybe able to find a similar system on a second gen Z28, i know they use a electric solenoid and use a switch on the pedal, it looks just like the kickdown switch used on a TH400.
__________________ "Speed has never killed anyone, suddenly becoming stationary... that’s what gets you.”-Jeremy Clarkson ,TopGear
I'd thought of using a solenoid but not one that was actuated by the pedal position, that's a pretty slick idea. I like it. I guess it wouldn't be too hard to fabricate something that would work. The only hitch that I can see is that since I really don't know how the air cleaner part of it is supposed to be plumbed I'd be afraid of having the scoops open while it was raining & wind up ingesting some water, although I suppose it wouldn't be too hard to wire in a dash mounted kill switch for it. The only problem with *that* solution is that it requires the driver to put some actual thought into the driving conditions and respond accordingly & I'm building this car for my kid who historically doesn't put a great deal of thought into *anything* that he does. However it gets installed I need it to be idiot-proof.
Last edited by Broncobill78; 10-30-2009 at 03:35 PM.
I had a friend with one (maybe he'll chime in...) who made manually removable flaps for his. They were placed in the hood one day when it rained and he went to fire the car the next day and it hydrolocked. Fortunately the starter broke apart instead of a piston or a rod and it ran fine afterward.
But it just leaked around/through the top of the air filter and down into the motor. Crazy.
LOL..some of the first '82 C/F z28s did have a problem
with water getting through the hood flaps and collecting
in the engine-the air cleaner was quickly modified to
prevent this
Back in 1991,when my car still had the original LG4
engine,i made my non functional SMC hood into a ram
air hood by cutting out the blocked off openings,made
some motorized flaps,built a fiberglass airbox under to
mate to an'80 z28 aircleaner used silicone rubber to
secure the airbox to the hood as fiberglass resin would
not stick well to the SMC material.A microswitch on
the carb opened the flaps,manual switch too
An improved version of this setup is on my car today,
feeding a modified 350 CFI engine