[bigwildgrin]

okay I built a big hot rod engine for my pontiac, but now it doesn't fit under the hood. so, and this makes me so sad I could cry, I cut a hole in my hood and slapped on a fiberglass scoop. I've tried two different scoops and they both look good at first but then a nasty crack appears in the seam where they mount to the hood. I've taken some time to look the situation over and I think I've weakened my hood by cutting it and it's flexing when I open and close the hood. the car is going to be painted again and I dont want any more problems, so would I be better off going with a bolt on scoop or a metal scoop and welding it on, then using filler to finish it? I'm not a real good body man so I'm leaning towards a bolt on cowl induction scoop, but I've never seen one up close and would like to know how they look. but then I got to thinking, if they look good, why would anyone waste time and effort with a bonded on scoop? any of you guys ever use a bolt on scoop?

[kenseth17]

Unless for some reason interior hood supports were cut or a really large hole were cut, I don't think cutting a small hole in the top hood skin is the problem. Fiberglass and metal are too different animal and expand and contract differently, which can mean problems at that seam. The best bet would be weld in a metal scoop. But if installing fiberglass I would make sure scoop is fiitting good to hood, grind both the hood and scoop where they will meet, and install with a panel adhesive, screwing the scoop into place while the adhesive cures. Then blend in with plastic filler. Adding support to the area can't hurt though.
I put one on two years ago using fiberglass mat and resin, screwing into place and then blending in with more fiberglass mat and resin, followed by plastic filler. Seen it not too long ago, and knock on wood, no cracks at seam yet. A Panel adhesive would be easier and I believe even better to use.
I Like cowl induction scoops but If buying a fiberglass hood it can mean fit problems and a lot of finishing work on the fiberglass, so try to find out more about what kind of luck others are having with the manufacturers parts. Unless you are talking just bolting a a cowl induction scoop. Depends on if you mind a seam or not, I never installed one of those, or really payed attention to them close up and looked if they were bolted on. Here is a pic of a bolt on cowl style scoop found in an image search, granted not a pontiac.

[1957plymouthhemi]

".....okay I built a big hot rod engine for my pontiac, but now it doesn't fit under the hood......."

Man don't you just hate that

I went thru that building my 57 Plymouth, the Tri-Power Hemi just would not let the hood close even after lowering the air cleaner as much as possible and I was determined that I would use that intake on the car.

First problem was not being able to find a scoop in the aftermaket that looked good on the car. I finally started looking in the wrecking yards different hoods and decided to use the hood scoop section from a 63 T Bird.

I cut the section out and trimmed it for a nice fit then I talked to several body guys and they all told me there would be a lot of warpage problems welding the scoop on so I decided to go the bolt on route.

I welded 6 studs to the bottom of the scoop (3 on each side) and thats what holds it to the hood. Individually the 2 pieces are very flexable, but assembeled the hood is more rigid than it was originally. As a bolt on there is no bondo or welds to crack.

I edged the bottom (and the hole in the original hood) with door edge guard. The trim on the scoop makes a nice finishing touch and keeps paint from getting scraped during installation. (There are pictures in my journal)

I realise that this solution may not be for you. I got lucky and found a scoop that went very well with the car and was tall enough to give me the clearance I needed.

Besides the functionality of the scoop, I have a custom feature on my car that looks like it belongs there and not everybody else could duplicate by picking up a catalog. In the long run it was also considerably cheaper than buying a fiberglass scoop and having it installed (I paid almost nothing for the hood because on rust bubbles on the forward edge a rather large dent in a place on the hood that was cut away anyway).

Anyway thoguht I'd throw the idea out for you.

[75gmck25]

I had a functional scoop on my '69 Torino Cobra. It was bolted on to the hood using studs on the bottom of the scoop and nuts under the hood. It worked well and was very stable.

Bruce

[rj57]

One thing if the scoop opening is towards the front of the car this is why it's cracking on you. The scoop is scooping up air as you drive. A way to get past this is relief holes in the back of the scoop. So all the air that enters the scoop isn't forced down towards the engine.


A local '55/6/7 Chevy club I was in 20 years ago, a lot of the members were grafting Chevelle cowl induction scoops on their cars. I liked it so I found a guy parting a '71 Chevelle. Bought the hood for $75, took it home and wacked the cowl scoop out of it. The girl I was dating knew a man who welded the cowl scoop to my stock '57 hood.

A little bondo work, + paint and people ask me if '57 Chevies with a cowl scoop hood was an option in 1957?

I'd had people tell me they remember '57 Chevies having these kind of hoods.

The club I used to be in, everyone painted their cowl scoops body color and to me the scoop blended in. I wanted mine to stand out so I painted it the roof color.

[Bee4Me]

For what it's worth,
Harwoods bolt on is a nice piece. Comes with a gasket for scoop/hood fit and is a sturdy unit.
One problem could be that your tightening it down too much if it is a bolt on and that could be what is causing the breakage. I've seen a lot of these at the track and nobody has complained about breakage.
If you had to cut the X brace,you can tack weld the "ends" too the hood for some flex support but you'll have to finish them and paint.
An adhesive like 3M or Fusor would work as well but they are not cheap and you have to use the special caulking gun to apply them but this won't require any paint work. Most paint stores will loan you a gun or at least require a deposit.
Molding one into the hood is a time consuming process and if it's not done correctly WILL crack after awhile.

NICE job rj.

[Nightfire]

If none of the above advise works for you, just get a butterfly scoop on your carb and run it without a scoop. Make sure to put some kind of lining around the the inside of the cutout though.


Mike