289 comp cars hood scoop attachement

289ACE · #1 (**permalink**) 07-10-2007, 01:32 PM

I have what I believe is an original hood scoop that I am planning on using on my car. When I went to talk to a potential painter about painting my car he said we might have a problem with the hood scoop moving around and scratching the paint and has suggested using a thin rubber gasket around the perimeter of the scoop. When I look at the pictures of the original scoops it looks they were molded in pretty well with the finished hood (ie no seam) so I am wondering how they were assembled on the orginal cars. In particular I am wondering if body filler was used on the edges, or if something else was done. The scoop I have is the style where the front lower portion is about 3/4" forward of the top and it is attached at the rear with 4 rivets/screws and then there is a scoop insert which screws to the hood and the scoop rivets/screws to it. The paint guy said if body filler is used on the edges, it will probably crack at some point, so I am looking for other solutions. Perhaps Shelby was never concerned about cracks so they just used filler and figured they would have bigger cracks/dents to deal with before they had a problem with the scoop. FWIW, My car is aluminum, but the scoop seems to be some other non ferrous material and here is a not so good picture, but you can get the idea.
TIA,
Jay

Three Peaks · #2 (**permalink**) 07-10-2007, 01:44 PM

EPoxy, pop rivets, or maybe solder it on?

Tom Kirkham · #3 (**permalink**) 07-10-2007, 04:57 PM

For that style hood scoop the were butt welded into the hood

289ACE · #4 (**permalink**) 07-11-2007, 01:47 PM

Thanks Guys.
Tom, since the originals were welded on, I think that would infer the original scoops of this style were aluminum? Mine does not seem to be aluminum, so I think I'll have to come up with something different if I want to use this scoop. It already has rivets/screws for attachement, so maybe 3 peaks idea of solder in the seam area would work. It seems like solder might be more forgiving that bondo, more thermally stable, and less susceptible to cracks. Anyone painted over solder on aluminum that has any comments?
Thanks,
Jay

Tom Kirkham · #5 (**permalink**) 07-11-2007, 04:03 PM

Yes the original FIA style hood scoops were aluminum. The hood scoop used on 427 comp, SC and some 289 cars were fiberglass.

Here is a picture of the underside of an FIA hood.

Rick Parker · #6 (**permalink**) 07-11-2007, 04:42 PM

If you check with a Body Shop Supply company there are structural adhesives available that remain semi pliable and can be sanded, primed & painted. "Lord" is one company and I am sure 3M is another. The applicators mix the two part epoxies as they are dispensed from a tool similar to a caulking gun. I have used Lord's product (several available depending on parent materials) more than once to bond aluminum to fiberglass. Aluminum l has to have a self etching epoxy primer applied before the adhesives will bite. They are used by GM in OEM manufacture of the Corvette for attaching body panels and substructure components to each other, this is real strong stuff. I believe you would have better luck with something like this than "Bondo". The thin aluminum on the hood will "move around" alot due to thermal changes and flex of the thin metal. The original cars scoops, seams etc. were gas welded and metal finished.

csx700? · #7 (**permalink**) 07-11-2007, 04:55 PM

early 289 comp cars had scoops that were riveted on. later comp cars such as the usrrc and fia cars had scoops that were welded into the hood.

Tom Kirkham · #8 (**permalink**) 07-11-2007, 06:37 PM

The LeMans cars (CSX2131, etc) also had welded in hood scoops

tcrist · #9 (**permalink**) 07-11-2007, 07:22 PM

Try sikaflex. We use this at work and paint over it.
http://www.sikaautomotive.com/auto-product-flex.htm

Terry

csx700? · #10 (**permalink**) 07-12-2007, 08:02 AM

your correct tom on the lemans cars,i believe very close to the same scoop as the usrrc / fia cars.

289ACE · #11 (**permalink**) 07-12-2007, 01:10 PM

Thanks guys great info! csx700?, do you know how the edges of the riveted scoops were finished, or maybe they were left open? It looks like there are many products I can use for filling the area in, but now I am wondering whether they were done that way originally.
Jay

csx700? · #12 (**permalink**) 07-13-2007, 08:35 AM

the scoops were just riveted down and not blended into the hood.

289ACE · #13 (**permalink**) 07-14-2007, 08:55 AM

Everyone,
Thanks again for all of the information. Now I have to get going and do something.
Jay

Rick Parker · #14 (**permalink**) 07-14-2007, 10:19 AM

Is there a source for a fiberglass version of this scoop?