Advice on Molding a Vent Into a Fiberglass Hood.

Discussion in 'Body Restoration' started by sandiego74, Jan 29, 2018.

  1. sandiego74

    sandiego74 Veteran Member Lifetime Gold Member

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    Feb 23, 2009
    San Diego, CA
    Just picked up my flat bolt-in-rear, pin-on-front fiberglass hood from Unlimited. Haven't had a chance to fit it yet, so I can't report on it's exact fit and finish yet. However, I plan on putting a vent on the hood, and one of the gentlemen at Unlimited recommended I find a body-shop that will do it for me. How hard could it be?

    This is exactly what I want to do with mine, with the hood vent from a 2014 SS/Z28.
    https://www.thirdgen.org/forums/fabrication/708383-2014-hood-heat-extractor.html

    I also have to add the hood pins, so I'd really like to keep the cost down and do it myself.
     
  2. jimrr

    jimrr Veteran Member

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    Jun 12, 2016
    sarasota
    That's just a proper cut. Buy the extractor and cut it into cardboard, then cut your hood from that template. Epoxy it down....done.
     
  3. 8pack

    8pack Veteran Member Lifetime Gold Member

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    Pittsburgh, PA
    It looks like there was some fiberglass work behind the extractor to get rid of the ridge and flatten it out.....I doubt it is that hard, but I would get an estimate from a body shop, for the cost it may not be worth your time....or you do 90% and let the body shop do the finish work to get it perfect for paint.....

    After looking again, in the first pics of the hood where the back of the scoop was flattened ut looks pretty rookie....I think you need to get that right to make it look right...in the second set of pics with the rain on the hood I think they did a much better job....unless it is the same car and they just got it finished properly....

    I like the idea, looks cool.
     
    Last edited: Jan 29, 2018
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  4. Blown Camaro

    Blown Camaro Veteran Member

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    Deltona, FL
    That ridge down the center will give you problems when mounting to a flat hood. You can make a flared ridge to mate up with it. Not sure what you fiberglass skills are but I could do it.
     
  5. sandiego74

    sandiego74 Veteran Member Lifetime Gold Member

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    Feb 23, 2009
    San Diego, CA
    I'll definitely get a quote. My fiberglass skills are at the I-have-never-worked-with-fiberglass-before level. Lots of information on the internet and YouTube, though, so I figured it couldn't be that hard.

    The cardboard-cutout is a great idea. Any type of epoxy will work? Any specific way to cut it?

    Also, for trimming and shaping the edges, just regular sanding methods will suffice?
     
  6. sandiego74

    sandiego74 Veteran Member Lifetime Gold Member

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    Feb 23, 2009
    San Diego, CA
    Also, where do you think I should put the vent on the hood? Ideally, I'd like to put it right over, or at least partially over the air cleaner so cold air can be directly sucked in through the top since I have once of those K&N top-filters. However, would that be a bad idea with the possibility of water directly hitting the filter (even though it hardly rains in San Diego)?
     
  7. 8pack

    8pack Veteran Member Lifetime Gold Member

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    There are several different kinds of resins you can use. Epoxy will yeild a better result than polyester resin on your hood. Mixing ratio accuracy is very important and for some it is by weight and others by volume. Research thoroughly before you buy. West systems seems to be a pretty safe standard. Also, the fiberglass mat you use is important as well. Aircraft Spruce is a great resource and they are helpful. They specialize in aircraft construction.

    I believe there is a tray you can get for the scoop that keeps the water off the engine .
     
  8. NOT A TA

    NOT A TA Veteran Member

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    Feb 12, 2009
    Delray Beach Florida
    That vent is intended to draw air OUT of the engine compartment due to the pressure difference above/below the hood while the car is moving. The only way you could draw cool air into the carb using it would be to use a pan enclosure under the carb that is sealed to the hood or seal the air cleaner somehow to the hood or vent.
     
    Last edited: Jan 31, 2018
  9. sandiego74

    sandiego74 Veteran Member Lifetime Gold Member

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    Feb 23, 2009
    San Diego, CA
    Great point! I didn't think about that.
     
  10. budro6968

    budro6968 Veteran Member

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    Jax Florida
    The Whole idea of the cowl induction is to force air in at the back of the hood B/C that is a high pressure zone due to the windshield being in the stream of air it will force it in the rear scoop. I think the vent will look cool but defeat the purpose of the rear scoop. Just my 2 cents.
     

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