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hood scoop

Depends on if your hood is steel also. if so you can always pop rivet it on. Has served me well at the track in the past. I've had the misfortune of making a 160 MPH pass at the track and the bonded hood scoop departed from the car. Good luck with your endeavor.
 

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Faith - Respect - Trust
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Pop rivets have held hood scoops on hoods for many years in the past, however, with the quality of adhesives today, gluing a scoop on is the method of choice. 3M's 08116 and 08115 body panel adhesive will hold quarter panels on cars and some manufacturer's even go to greater extremes for the use of body panel adhesive.

If you do choose to use body panel adhesive the difference in part #'s I gave you in 3M is speed only. The 08115 and 08116 will give you plenty of work time to make sure your scoop is on straight and where you want it. I just checked my fastest 3M stock and the part # is 08147....this will give you a work time of 20 seconds and bond time of 30 seconds with total cure in 1 minute....much to fast for your application but, just to let you know how fast they can make adhesivesand there is a range of product in between the 1 minute cure time and the overnight cure time of the 08116...(Come to think of it I don't know what I would need to bond together that quick for myself or why I have it....must of been a sample from the 3M guy).

3M is an expensive product but, does work well, other manufacturer's also make adhesives that are a bit easier on the wallet like Norton, Dominion Sure Seal etx.

Hope this helps.

Ray
 

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I've only done one of these. I used the Valvoline Pliogrip. It was the first time I'd used such an adhesive. I was a little apprehensive about trusting a glue on a hood scoop. So as per the reps instructions I applied the adhesive and then screwed the panel down to the hood. I don't know about other brands but what I was using had micro beads in it so that when screwed down the beads kept you from squishing all the adhesive out of the joint. Once the adhesive was set I removed the screws and welded the holes shut.
 

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weld or bond

Yeah...he's probably right. With the quality of today's adhesives, especially by 3M, you can simply bond it and have bo problems at all...and they would serve to seal out unwanted dirt, debri and water that may otherwise get sucked between the hood and scoop from riveting. I'm still a little old fashioned I guess...or just old.
 

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Brian Martin,Freelance adviser
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A couple of little tips on these adhesives use. First off you want the metal perfectly clean where the bonding will be. Running a nice new sharp 50 grit disc on the area is a must. We are talking only the areas on both pieces where they meet and the adhesive will be applied, be sure it is spotlessly cleaned with a NEW 50 grit disc, preferably a little 3" disc on an air angle grinder. It allows for much more control than a larger disc and tool.

If you have a large mating area like setting a hood scoop on top of a hood you will want to trail fit the scoop getting it on there perfect and marking all the way around at the edge. You could even mask off the hood around the scoop, you don't want the adhesive being anywhere but where the scoop meets the hood. The adhesive doesn't like to be pianted, or filler applied to it, you don't want it oozing out all over the hood. If you don't have large C clamps (24" Vicegrips are awesome tools to have) then you need to hold it down with screws until the adhesive cures. Heat is the arch nemesis of these adhesives so you can't weld up the holes if the glue is coming close to it. But if you remove the screws and fill it with a reinforced filler like "Everglass" that is as good as you can get using this method but there is still chance for "ghost lines" where those holes are.

Once the areas are cleaned like you apply a bead of the adhesive to BOTH surfaces. Then using an "acid brush" (anything will work to spread it out but they work so well) spread out the adhesive over the complete area where the two will be meeting. Brush it out over the entire mating area so there is no bare metal on both the hood and the scoop.

Set the scoop into place trying not to lift it up after the adhesive strips have made contact. If you have to move it a little slide it, but don't lift it, this creates air bubbles.

Clamp it into place with long C clamps or the screws until it sets as per manufacturers recommendations. Cleaning the adhesive out of the edge where it meets good after it's cured and applying an epoxy primer over it is as good as it gets.

If you plan on moulding the scoop into the hood, that is asking for trouble as the edge will likely show a ghost line after you are done and out on the road. But if you insist, applying something like Everglass (a very short strand fiberglass reinforced filler) over the seam making sure to leave a thin film over it, it can work remarkably well. But more likely than not you are going to end up with Ghost lines down the road.

Brian
 

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Brian Martin,Freelance adviser
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Yeah...he's probably right. With the quality of today's adhesives, especially by 3M, you can simply bond it and have bo problems at all...and they would serve to seal out unwanted dirt, debri and water that may otherwise get sucked between the hood and scoop from riveting. I'm still a little old fashioned I guess...or just old.
BMW guidelines on sectioning the main frame member on a 7 series tells you go bond it with a structural adhesive and that is it, no welding, nothing. :thumbup:

Brian
 

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Doesn't it use expanding foam to make the sleeve expand into it? And then it takes structural adhesive to adhere it to the sleeve? I saw that in either in The Icar adhesive bonding or automotive foams class. Might have to pop it into my computer to refresh my memory. Unbelievable how they have a math formula to figure out where the foam will stop and expand as gravity moves it down inside a pillar. Pretty tech stuff. When I go back to production I'm going to Duane's. They do all that nerdy stuff by the book there.
 

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Brian Martin,Freelance adviser
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Where I work we have all our ICAR stuff for the insurance companies we work with. Over the years I have went to a number of them, outside of one that pops out in my head they all gave me a lot of interesting info. The one that gave me nothing, still taught me something. That was "Advanced systems" talking about ABS, SRS, Engine management, that stuff. What it did for me was "demystified" it, didn't teach me a damn thing about fixing anything but it did demystify it for me a little. But the last one was that foam class and I thought it was going to be a waste, it was darn good. I had all kinds of foam ideas in my old cars going thru my head as the class went on. :D

I don't remember how the foam would be used in this hood scoop project though, what exactly are you thinking?

Brian
 

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I wouldn't use foam for a hood scoop. Just thought that procedure for the glued on rail included an expandable insert that used foam to expand it. I can't seem to remember but recall that being talked about in either the foam class or adhesive class. I also thought that foam class was cool. It took me by surprise as I was just thinking it was one of those filler classes where it's one you just need for the points but it was actually a good one. A couple structural ones are really good too.
 

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Brian Martin,Freelance adviser
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No foam, it uses a metal sleeve that goes in the rail extending a few inches on each side of the splice. It has a bolt you run down into it and when you tighten the bolt it expands the sleeve which is bonded in.

Brian
 

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if I can figure out how to reinforce the 71 c-10 hood, I want to use my goodmark 4" cowl scoop and mount it like the prostockers did, and well to a small % like the 70's t/a..
making a long carb plate and have the cowl sit on it.. and the hood close over it.. like a shaker, or a prostocker aero scoop.. did..
cutting 75-80% of the lenth of the hood out of the middle.. it'll need some reinforcement.. thinking u channel and weld to the wopping two reinforcement ribs and some foam between the inner and outer parts..
hope to find a hood I can hack thats dented in the center.. found one local j/y now hope it's still there.. lol.. (at the time I didn't have this idea running in my head) figures lol
 
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