ChipBeck Posted April 18, 2008 Report Share Posted April 18, 2008 Gentlemen, As I promised yesterday in the "hood scoop saga continues" thread, I am posting today photos of the repair I made on my hood scoop. This work was not covered under my factory warranty nor did I ask or expect it to be. Some brief background. I am a Shelby fanatic and I consider the Shelby GT to be the purest Shelby Mustang since the last 1966 GT350 was built. My collector cars are all kept in immaculate condition including a Ford GT, and an aluminum bodied Cobra. I absolutely love my Shelby GT but the soft plastic hood scoop was driving me nuts. The original was horribly warped and the replacement sent to me by Shelby was slightly dished out in the rear before I even tried to put it on the car. I am a former test pilot for a composite propeller manufacturer as well as a composite aircraft builder. I have worked as the Airshow demonstration pilot for the Stoddard-Hamilton Aircraft Company and Phoenix Composites in Mesa, Arizona and consider myself to be very well-versed in composite materials and their suitable uses. In my opinion, there is no way to fix the factory Shelby GT hood scoop without changing the material it is made out of. The scoop, as supplied by Shelby, is injection molded using a plastic that is somewhat softer than a Tupperware bowl. Look at the two enclosed photos. In the first, my technician is holding the factory scoop by the corner and it bends under its own weight! When left in direct sunlight it heats up and gets incredibly soft. In the second photo you can see how much the scoop bends when twisted with a very slight amount of force. The latest Shelby fix is to supply this scoop with a black foam rubber insert that is intended to support the scoop and keep it from collapsing or warping when it gets hot. Attaching such soft plastic with rivets without damaging that soft plastic or the paint applied to it is almost impossible. The soft plastic in that scoop also expands and contracts a great deal with changes in temperature. When it contracts it pulls the vinyl stripes pinched between it and the aluminum hood inward and when it expands it pushes those stripes outward causing them to bunch up around the edges of the scoop. Here in Arizona I have examined over a dozen Shelby GTs and almost all of them have warped scoops, damage to the paint and/or the scoop itself from the riveted installation, and damage to the stripes at the edges of the scoop from expansion and contraction. Using a different scoop or removing it entirely destroys the originality of the car and that is unacceptable to me. So utilizing the expertise I have available I changed the material that my scoop is made out of, and I changed the way it is attached to the hood. Let me make it clear right off the bat that I am not manufacturing duplicate Shelby parts nor do I have any intention of doing so. This is a repair of a defective part on my car. Carroll Shelby has been a good friend to me and the entire Ford GT community and the rights to manufacture and all profits from parts that they design are rightfully the property of Mr. Shelby's company. The scoop I have made differs in materials, construction method, interior and exterior shape, and method of attachment. It is strong enough to stand on in one's bare feet, requires no internal bracing and therefore allows one to make the scoop functional, and it is constructed of aviation grade vinyl-ester impregnated fiberglass. It is attached to the hood using Rivit-Nuts and chrome plated hex head dome top screws which allow the scoop to be removed and reinstalled any time in just a few minutes. These rivet nuts also allow me to screw the scoop down with just enough pressure to hold it securely but not so much pressure as to damage the hood or the scoop. This of course, would not be possible using standard rivets. The original hood scoop is painted silver and the white stripe in the middle is a tape stripe. This allows Shelby to install the scoop on the car and then line up the stripe on top of the scoop with the striping on the car itself. The stripes on the hood of my Shelby GT are not aligned with the center of the hood and are offset about one third of an inch to the right. My replacement hood scoop as you can see from these photos is lined up perfectly in the center of the hood but is not lined up perfectly in the center of the stripes. So I am going to remove the stripes from the hood of my car and reinstall new ones that are lined up properly. That done, I will have the perfect Shelby GT Mustang. The first two photos show how soft and pliable the original hood scoop is. Photo number three shows my original hood scoop on the right and the one I had built out of fiberglass on the left. Photo number four is a close-up of an installed Rivit-Nut and the chrome plated hex head screw that I use to attach my new fiberglass scoop. Photo number five is my hood with all rivet nuts installed in the exact same location as the dummy screws were on the original scoop. Photo number six shows the bottom of my hood with the insulation removed so you can see the rivet nuts protruding slightly through the bottom of the hood. These rivit nuts will be hidden completely when the insulation is reinstalled. Photo number seven shows the unpainted-primered scoop being bolted to the hood so I could take some photos. Photo number eight shows the scoop fully bolted down to my hood. Note how the stripes are not perfectly centered on the hood. I will be removing and replacing my stripes so that they will be properly centered. Photo number nine shows the scoop from the side. No waves, no dips, no imperfections!! This scoop is made out of the exact same material as my aircraft that is sitting in the photos background. Photo number 10 shows my original hood scoop sitting on the hood next to my new fiberglass scoop installed. Photo number 11 shows both scoops from the front. The last photo I am including is a photo of the cowling of my Glasair III aircraft. The engine cylinder heads are less than an inch from the vinylester resin fiberglass underneath the word "Phoenix". That engine cowling is over 10 years old and that fiberglass has been subjected to engine heat in excess of 400 degrees for long periods of time followed by cooling to below freezing during wintertime. As you can see it is still perfect after a decade of extreme heat cycles, 400 mph air speeds, and loads in excess of eight G's. In about a week I will paint the silver and white on my hood scoop and I will post final photos at that time. All the best. Chip Beck Link to comment Share on other sites More sharing options...
ChipBeck Posted April 18, 2008 Author Report Share Posted April 18, 2008 Photo's 4 & 5 Link to comment Share on other sites More sharing options...
ChipBeck Posted April 18, 2008 Author Report Share Posted April 18, 2008 Photo's 6 & 7 Link to comment Share on other sites More sharing options...
Grabber Posted April 18, 2008 Report Share Posted April 18, 2008 Now that's taking things into your own hands. Very impressive job you have done there. Link to comment Share on other sites More sharing options...
ChipBeck Posted April 18, 2008 Author Report Share Posted April 18, 2008 Photo's 8, 9, & 10 Link to comment Share on other sites More sharing options...
ChipBeck Posted April 18, 2008 Author Report Share Posted April 18, 2008 Photo's 11 & 12 Link to comment Share on other sites More sharing options...
GTH391 Posted April 18, 2008 Report Share Posted April 18, 2008 Truly impressive. Your process was a very interesting read as well. Nice job, well done. You're gonna get a lot of hits for scoops..... Link to comment Share on other sites More sharing options...
ingram4868 Posted April 18, 2008 Report Share Posted April 18, 2008 Great craftsmanship !!!!!! Link to comment Share on other sites More sharing options...
stormeaston Posted April 18, 2008 Report Share Posted April 18, 2008 Oh yeah, I was going to do the same thing..................except my fix included alot of duct tape and............never mind yours is better I guess. <_< Just pulling your leg, very impressive and a great fix. My scoop is not that bad yet, I've had some ideas on what to do but I'm going to wait until it gets really bad and then do something. Link to comment Share on other sites More sharing options...
RStangsOC Posted April 18, 2008 Report Share Posted April 18, 2008 Excellent writeup - and excellent piece of work. I wonder why Shelby didnt make the scoop of hard urethane? We manufacture thousands of pieces of automotive urethane here each month (many of which are under the hood - n hot conditions) - with no problems. Link to comment Share on other sites More sharing options...
JeffIsHereToo Posted April 18, 2008 Report Share Posted April 18, 2008 What can I say other than WOW! Link to comment Share on other sites More sharing options...
mywickedshelby Posted April 18, 2008 Report Share Posted April 18, 2008 Mr. Beck, When and if you ever build a second generation hood scoop, I would like to buy your prototype for installation in my SGT. Respectfully, Wicked Link to comment Share on other sites More sharing options...
blueshawk Posted April 18, 2008 Report Share Posted April 18, 2008 What can I say other than WOW! Yeah, WOW In a private email, I asked Amy to look into using "rivnuts" when they were looking into rivets. SAI decided on rivets. Looks like "rivnuts" was the way to go. Link to comment Share on other sites More sharing options...
07SGT0547 Posted April 18, 2008 Report Share Posted April 18, 2008 Chip, I'll take one anytime you are looking for the "average Joe" to get one installed... Price??? Thanks! 07SGT0547 Link to comment Share on other sites More sharing options...
ilmor Posted April 18, 2008 Report Share Posted April 18, 2008 Your solution appears to be a great answer...hopefully you can work out a deal with your friends at Shelby to provide one (installed and finished) to each of us in lieu of what they sold us. Link to comment Share on other sites More sharing options...
Shelby-Don Posted April 18, 2008 Report Share Posted April 18, 2008 Any way of getting one of these Link to comment Share on other sites More sharing options...
SGT/SC#0471 Posted April 19, 2008 Report Share Posted April 19, 2008 Chip nice...how much for the mold as you are done with it. Realistically any competent glass dude could fab one up with some plaster and wax,but as you have already done this...White looks good as is BTW. Cool! Link to comment Share on other sites More sharing options...
ChipBeck Posted April 19, 2008 Author Report Share Posted April 19, 2008 Any way of getting one of these Gentlemen, Anybody that wants one can have one. I spoke to the technician who hand built mine and and asked if he was willing to make any more. He told me that if I did not object, as I have just spent a ridiculous amount of money to fund this one off project, and with the understanding that this scoop differs slightly from the original in shape and differs completely in its construction and materials, that he would make one for any Shelby GT owner that has a problem with his factory scoop. They would have to be made one at a time by hand and although they would be considerably less expensive than the amount of money I just paid, this would still not be cheap. Heath will be on vacation until April 28 and upon his return I will put him in touch with anybody who contacts me via PM. I have no financial interest whatsoever in this project. My scoop was not made using a mold of an original. It was made using eyeballs and measurements which is why it's slightly different and of course unlike the original, this scoop is immediately recognizable as being a non-Shelby piece because it is open in the front. Heath told me that if he could take a mold of my scoop while it is still in primer, that would reduce the amount of labor necessary to produce others. But there would still be a lot of hand labor in the layup, standing, finishing, and drilling to produce a finished product. What will it cost? I don't know and I won't be speaking to Heath again until his return on April 28. What I do know is that this is a man who builds jets and his work is aircraft quality. If somebody wants a cheap fiberglass knock off, Heath would not be the guy. Again, I'll make a list of everybody who sends me a PM and I'll pass it along to Heath on April 28. Cheers. Chip Beck Link to comment Share on other sites More sharing options...
Dig-It Posted April 19, 2008 Report Share Posted April 19, 2008 Definitely interested! Thank you for blazing this trail Chip! Link to comment Share on other sites More sharing options...
ilmor Posted April 19, 2008 Report Share Posted April 19, 2008 Just thinking out loud...if I get a new scoop, its got to come from Shelby...not that what is being discussed here is a bad thing, I think its great. But its not for me, unless it becomes the only other option someday. By then there will more than likely be other options available as well, at reasonable prices. Link to comment Share on other sites More sharing options...
Webba Posted April 19, 2008 Report Share Posted April 19, 2008 What is the possibility of hooking Heath up with Amy or whomever at SAI. Great job Chip and your guy Heath. This is the way to go. Link to comment Share on other sites More sharing options...
JeffIsHereToo Posted April 19, 2008 Report Share Posted April 19, 2008 of course unlike the original, this scoop is immediately recognizable as being a non-Shelby piece because it is open in the front. This does also raise the possibility of a functional scoop if someone wanted to create the airflow foil from the scoop to the CAI box! :happy feet: Link to comment Share on other sites More sharing options...
bobr13 Posted April 19, 2008 Report Share Posted April 19, 2008 I have bought other aluminum and fiberglass scoops from other vendors previously to see if anyone else has a solution. The size of other aftermarket scoops is noticeably different, I posted pics in an old thread. This looks like the best choice so far, if you don't care about warranty work, pure originality for resale in 40 years, etc. Personally, I had a local Mustang performance shop bolt on a Gen 2 Whipple SC, so I obviously value fun and performance over warranty and collectible status. Things like this are what make this forum such a valuable resource, more choices and solutions for everyday issues. Thanks again to Chip and his glass guy. Link to comment Share on other sites More sharing options...
SGT/SC#0471 Posted April 20, 2008 Report Share Posted April 20, 2008 How do you make this without a mold? Layup over the original scoop? Link to comment Share on other sites More sharing options...
SGT/SC#0471 Posted April 20, 2008 Report Share Posted April 20, 2008 Photo's 11 & 12 I like the scoop in white. I do not understand how the correlation between the all glass cowling of your plane and the aluminum interface of hood and glass scoop relates, but nice picture... Link to comment Share on other sites More sharing options...
ChipBeck Posted April 20, 2008 Author Report Share Posted April 20, 2008 I like the scoop in white. I do not understand how the correlation between the all glass cowling of your plane and the aluminum interface of hood and glass scoop relates, but nice picture... The correlation to the vinyl-ester resin fiberglass cowling of an aircraft is made to reference that materials proven strength, heat resistance, stability, and long-term durability in an extreme environment. The stock hood scoop on the Shelby GT is not subject to anywhere near the heat or stress of an aircraft cowling and it still has a near 100% failure rate because the material it is made out of is too soft, too flexible, and prone to warp, shrink, and expand because of changes in temperature. It is also easily damaged when installed using rivets. Of necessity, modern piston aircraft engines are air cooled and must be very tightly cowled to minimize wind resistance. This places the fiberglass within a fraction of an inch of a red hot air cooled cylinder head. Since that material can survive for over a decade without warping, shrinking, or expanding and still look perfect when used in the extreme service of an aircraft cowling, it can certainly do the same in the far more friendly environment sitting on the hood of your Shelby GT. All fiberglass is not the same. Some are far more durable than others. I view the Shelby GT as an automobile, like the 1960s originals, that will be kept and cherished for decades. I would bet that many of them will never be scrapped and they will outlast their current owners, again, just like the 1960s originals have. When replacing my hood scoop I did not want to trade one problem for another. Overkill is better than not quite good enough. Our Shelby automobiles, their features, and their ownership trail is recorded in the Shelby registry for posterity. Unfortunately, they were built with a hood scoop that will not make it through a single cold winter or hot summer without warping. The scoop on the hood is in the owner's direct view every time you take it out on the road. I can't tell you how nice it is to drive my car now without seeing daylight between the back corners of the scoop and the hood and without seeing the ripples and dip. It makes the car feel faster and it makes me feel younger, smarter, better looking, and not quite so fat! Chip Link to comment Share on other sites More sharing options...
SWEDEMAN Posted April 20, 2008 Report Share Posted April 20, 2008 Great writing! +1 on the functionality of the scoop. I owned a 1966 GT350 hood scoop and it was functional, I could never understand why they did not make this scoop on thr SGT functional? Great work. Link to comment Share on other sites More sharing options...
JeffIsHereToo Posted April 21, 2008 Report Share Posted April 21, 2008 The scoop on the hood is in the owner's direct view every time you take it out on the road. I can't tell you how nice it is to drive my car now without seeing daylight between the back corners of the scoop and the hood and without seeing the ripples and dip. It makes the car feel faster and it makes me feel younger, smarter, better looking, and not quite so fat! Can you post pics of the final result? Link to comment Share on other sites More sharing options...
ChipBeck Posted April 21, 2008 Author Report Share Posted April 21, 2008 Can you post pics of the final result? Jeff, Heath will be back in town on April 28th. He will paint my hood scoop and I will post photos soon thereafter. I have decided to make the hood scoop functional for two reasons. First, the Shelby GT is a modern day re-creation of the 1966 GT350. The scoop on the 1966 GT350 was open to the engine compartment although it did not feed cold air directly into the air cleaner. Having the scoop open, or functional, makes it look better though I don't think it actually served any purpose as that opening in the middle of an automobile hood is a low pressure area. That's the reason the scoops on the 1968 Shelby Mustang were moved to a high pressure area in the front of the hood. So my first reason for making the scoop functional is to facilitate some airflow either into or out of the engine compartment and because it'll look great. My second reason is the upcoming installation at Shelby's facility in Las Vegas of my Ford Racing Wipple supercharger. I like the looks of the Whipple better than I like the Paxton and the Whipple produces more horsepower at lower RPMs which suits my type of driving. What I didn't like about the Whipple was having to remove the strut tower brace. We have taken some measurements and utilizing the additional clearance that the open scoop will provide we have engineered a modification to an existing Shelby strut tower brace that will clear the top of the Whipple AND will clear the bottom of my open hood scoop. Now I don't have to have one or the other, I can have them both. :happy feet: The Ford Mustang hood lends itself easily to this modification as there is no substantial hood bracing underneath the area of the scoop. As the hood is made out of aluminum, the opening will not provide the corrosion problem than it would on a steel hood. It will be several weeks before I can tackle the Whipple strut tower brace. I will post photos of that as soon as it is finished. Photos of my completed and functional hood scoop will be posted in about 10 days. Heath will post a price for a clone of my hood scoop, mounting hardware, and instructions, in about a week. All the best. Chip Link to comment Share on other sites More sharing options...
JeffIsHereToo Posted April 21, 2008 Report Share Posted April 21, 2008 Chip, Thanks for the update! Do you see placing a screen/grill of some sort at the mouth of the scoop? Any thought to crafting something to direct the airflow towards the CAI? Jeff Link to comment Share on other sites More sharing options...
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