Hood scoop

[1932]

I need to cut out big part of hood for cobra jet intake on aluminator xs. Going to build scoop over hole, but could use help on how to build the fiber glass scoop on and in the hood, it is two part.
Need to put blocks in to hold parts as one?
Start inside or on top of hood?
The scoop will be 14" x 3 or 4 in front, 28" long and 2" x 9 in back.
Looking for others info and help.
Thanks!

[erlihemi]

I'm risking tar and feathering with a side of blasphemy here, but... rather than cut a structurally double layered hood I went and got a cheap single layer hood online. 2 vendors both starting with an S supply 33-34 holds that are close enough to cut and reshape. The FFR hood put the strengthening ribs in the wrong place. I ditched the front hinge too. The other option is cut the underside first with a wheel and then build a structural " rim" about 2" around the outside of the expected scoop.

[1932]

I am thinking cut hood, put on car- engine is in car- fit hood and get all the measurements needed then pull engine, fit hood to car and build mold and glass on that.
Filling the space between top and bottom of hood with a plug, and with sides of scoop will make hood strong. Anyway that is my thinking now.

[mikeinatlanta]

6 or 8 lb density urethane foam is great for filling large voids in a double layer hood. It will also add a great deal of strength and rigidity to the hood. Just be VERY careful not to overfill and swell the hood or you will be tearing it all apart. Secret is to only a little at a time, letting each bit expand and cure before adding more. Remember, THIS IS NOT THE SAME A SPRAY FOAM.

For the scoop, I'd suggest glassing it to the outer skin first and then cleaning up and glassing to the inner skin later in the process. Just remember, the OE hood is made from vinylester resin. Polyester resin, especially cheap stuff like at Home Depot, will have a difficult time dealing with heat, and epoxy doesn't play well with vinylester. As a result, I suggest using vinylester for the mod, even if the actual scoop is made from polyester. If the scoop you buy is made from epoxy (very rare), then use a high grade polyester for the project. Just keep in mind that you want to avoid intermixing epoxy and vinylester.