I’m looking to make these for a new design car hood…
Here is a pic, but also the design is used by Seibon for their 2010 Camaro TS hood.
What do you think is the easiest way to chop up a oem hood and make it have this style of heat vents?
Oh yeah… if you ever asked yourself if heat extractor hoods work… yup they do 
If it were me (coming from someone who has never done this…) I would try cutting out 3 sides of a rectangular section, push it down and then, underneath the hood, weld in triangle-ish shaped sides. Then go from there making it look pretty and ready to pull a mold off (i.e. bondo, paint, polish, seal, release). Also, for the mold I would probably go ahead and close off the vent areas if you weren’t already thinking that.
Well if it were me I would make a mould of a standard hood first (that way you can also offer the standard hood for sale) plus the inside framework that you will need for your modified hood will also be the same.
Then make a standard hood from your new mould and mod that one and take a mould from your freshly modified hood.
That way your not distroying a standard hood and you can sell it after as they arnt exactly cheap are they! Also it would be easier to do your mods on a GRP hood rather than the steel one (unless your good at traditional panel beating work!)
Both are good ideas. If this hood were near perfect i would make a mold, then part, then modify part and make another new mold. The hood is peppered with hail damage. I have to bodywork the hood to remove the hail damage.
I tried a method a local bodyshop guy said may work for small hail dents. Using a small butane torch you do circles around the dent working in toward the center of the dent, hold it there a few seconds. Then you quickly cool it off with compressed C02 or dried ice. This worked pretty well on some of the dents. Clear coat is so darn tough it barely left a burn mark. I wanted to find a hail pop tool but haven’t found one yet. PDR techs have them… glue pop method.
I also have to bodywork the trunk and fenders on this car for mold making.
Lordy I hope people don’t put that hood on their car…imitation hood vents, that aren’t even cut out? Just as bad as 10 years of Mustangs, with a solid plastic insert in the hood vent SCREAM Anyway, make a mold, make a plug, mod the plug somehow, make a new mold. Maybe you can do something where you can take off the mod, add a new one in, so you have various designs off that one main plug!
Not being funny bud, but heat shrinking is a old system. by the time u have set ur gear up and done all that, i could of skimmed each dent and sanded the bonnet ready for a couple coats of durabuild.
Far quicker, but making a mold of the stock bonnet then a fibreglas item to modify is the best option in my opinion .Get some pics up of the current condition of the bonnet.
I’ll be starting on the hood project in a few days or so. Today i was so tired i felt dizzy and sluggish, so took most of the day off.
I did this 5 or 6 years ago by cutting holes in a junk hood, making the vent plugs, and then molding the final product into my FRP hood.
what did you coat the foam with filler/bondo?
I would highly highly recommend starting with a hood that’s in perfect condition. Try to avoid reworking the mold at all, and obviously the mold will only be as good as the part it’s made from.
It’s a good suggestion to make a mold of the OEM hood first. Capture ALL details, including hinge mounts and latch location(s). Attach a good backing structure to the mold before releasing from the original part to make sure it doesn’t twist or otherwise change shape.
Then modify the original hood with vents or whatever, finish to perfection, and make a mold.
To make several versions, make a perfect mold of the original using epoxy and preferably carbon, with a good backing structure. From that, make perfect parts again using carbon/epoxy, and modify them with any designs you’d like to incorporate. This will ensure that the parts are as close to OEM part as possible.
Any shortcuts or substitution of materials for lower quality will produce lower quality production parts. This is why the majority of aftermarket composite parts suck, and why so few companies can command premium prices for their high quality products.
I am going to have to change my design… heat extractor vents will hit on the radiator overflow and cold air shield. Consider this when making a hood 
I’m also changing the design to incorporate ram air.
Sorry, totally missed this. Yes, covered with bondo and sanded down. TETs advice is the best but I didn’t have a perfect hood to start with.
TET, after making the part from the mold, are there special tools required to cut up the part if made from CF? My understanding is that CF is harder on the tools, especially if the layers are thick.
Thanks
I find that a diamond cutting wheel in a air diegrinder is best
Matvd, i have heard this from someone else as well so that confirms A diamond wheel rocks
I did get our hood cut to the design shape. I am also removing the inside steel framework of the oem hood… it just got chopped up anyhow making the hood vents so removing much of the center section just makes sense at this point. I will use core material in the hood skin laminate to beef it up. the underside will still have the full perimeter support structure.
I’ll start working on that hood more with pics in a few days hopefully. I have just 15 days to make molds for trunk, hood, fenders, and all new cf laminated parts.
Your going to be busy then !!!
Good luck finding the time to post anything on these forums! If you find time though I wouldn’t mind some updates 
I got the plug nearly completed. I gel coated it today to make it all one color and be able to see the small imperfections that need smoothing before i apply the final coat of gel coat. My wife left the usb cord at work or i’d post pics. Customer is very happy with the design.
Any more progress on this with pictures of the process?
Here is pic of the hood plug. We have yet to make the mold for it.
I have some final bodywork to smooth out the small flaws. I just gel coated it white so i would have a clean canvas to see the flaws.
The fenders and trunk will be done in a few days.
I thought you had to have it done by now?!?!