I've been contemplating how to get a 507 looking hood. I've scoured the forums and based on costs..etc, I decided to cut my hood and give it a try. I went in knowing that I might have to buy a replacement hood depending on results. The 507 hood has the cut out edges turned down which gives the vent a flush mount look. I do a little body work on the side but that is a huge task, you would have to remove the stamped aluminum sheet glued to the bottom of the hood, tig or body fill the radius curves after making relieve slits...etc. Paint...etc. wow. above my skill level and pay grade.
Steps:
I know it is so lame to not have actual photos - I appologise up front.
I started by removing the under hood insulation and laid it on the engine bay to catch anything.
I made a template (photo below) based on another post
I bought some cheap vents to sacrifice for this experiment. (I may buy the carbon ones...)
I found that by turning the left vent upside down, it made a perftect pattern for the right side and vice versa.
I taped the upside down vents is place and transferred the outline to the hood with a fine, silver sharpie and taped everything off. (after measuring a thousand times)
I then drew the 'cut line' 3/16" INSIDE the outer line all the way around
I said ten Hail Mary's and started cutting the straight lengths with an angle grinder with a fine, metal cutting wheel (I used a worn 4" wheel for control) For the curves I used a dremel cutting wheel and a side cutter bit for the small curves.
After removing the hood cutouts you can now see the aluminum stamped piece that is rubber glued to the underside of the hood.
Fortunately, my cuts went thru two of these glued support areas - which helped with my fear of losing rigidity. (dia of these rubber mounts is 1.5 in)
I raised the hood and put the vents in from above to see where they were contacting the stamped sheet while looking up, cut out areas with an iteritave process until the vents dropped in.
My pictures are horrible - I know. note English conversions
Now came the most time spent because I believe these cheap vents ($35) were meant to be 'flush mounted'. I was going with the flange mounted look which was going to take a lot of time removing plastic to get the shape I wanted as shown in the pic. The vents are slightly curved to match the hood shape so trying to machine them wasn't going to work so I put them in a vise and used an angle grinder, belt sander, dremel and file to remove the plastic, all the while trying not to melt it and gum up the works - which does happen.
After hours of sanding/grinding and placing in the openings a thousand times to progressively get them to sit flush all the way around, I was ready to glue them in.
I also held up a 'dent light' around the openings to see if I had deformed the hood - Good news is there are so many curves which helps with strength. I couldn't see any warpage.
I then spread a thin film of SEM black seam sealer on the underside of the flange, 800 grit the hood where the contact would be, alcohol wiped and placed them both in the openings, pushed down hard and squeegied away the excess rubber.
I then put two cedar shingles (flexible) on top of each vent and then put 35 pound barbells on each vent and removed more excess rubber. (that weight did not deflect or damage the hood)
I know, I know, this 507 style hood is not original, TBH I don't care. It's not a show car, it's a 14 with high mileage. I enjoy walking across the parking lot and seeing that front end now. coming down the road it looks great.
For Phase II I will be drilling out the bottom of the vents and fabricating the drainage trays. (the original parts are too pricey)
If anyone would like to know more PM me.
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