What do you do if you want a Koguchi Power hood, but don’t want to pay $1,500 for one? If you’re like me, and you have a Harbor Freight welder, a few grinders, and bunch of scrap metal, you just make one yourself. Yes, it’s not going to look quite as nice. Yes, it’s going to take hours of cutting, welding, grinding and sanding. But, everyone has to have a hobby, right?

One of the big advantages of a fiberglass hood is weight. The stock hood is heavy as shit. To address this issue the first thing I did was cut out all middle framing under the hood.

With the framing gone the hood dropped a bunch of weight. More than I was expecting actually. I probably should have weighed it before and after, but I can safely say it weighed roughly the same as a BN Sports FRP hood. I also went around the outside frame and tack welded it to the hood skin just to be safe.

Once I had the back side all prepped I threw it back on the S13 so I could figure out where I need to cut things. I was going for a Koguchi Power look, but I also love the Car Modify Wonder hood, so I decided on a mix of designs. I spent a few hours planning out the bends and cuts.

I was as careful as I could be making the cuts with a cut-off disc on a grinder. They weren’t as straight as they should have been, but nothing that I couldn’t fix later.

I decided to use as much stock metal as I could so the front of the duct is just the stock metal pulled up and the rear is the stock metal pushed down. The arch of the hood made it a bit more complicated than I expected, but I got through it well enough.

I used 22g scrap to fill in the triangle on either side of the front of the duct. I was using 0.25 mig wire to avoid blowing through the thin metal with my cheaper welder. I still blew through a few times of course.

I was careful to make sure to measure the angle of the side on the LH side so I could match it on the RH side. The only “fabrication” tools I used were this angle finder, a grinder with a cut-off wheel and flap disc, and my trusty Harbor Freight welder.

I did the same thing for the back of the duct, which is just bent down stock metal with triangles welded on either side. You’ll notice the “hole” starts at the back of the radiator and goes to the front of the engine.

Then I added some more metal.

Then I added some “flaps”. Koguchi Power hoods actually have 3 flaps, and they are at a steeper angle. I decided to go with the Car Modify Wonder 2-flap design because it was less work.

Once everything was welded in, I pulled out the flap disc and grinded all the welds down. Then I started on the bodywork. I filled all the seams with fiberglass jelly (kitty hair) to blend into the duct into the rest of the hood.

The inside walls were the hardest part because I couldn’t get a flap disc or sander in there. I had to do all that sanding by hand. And it was a lot of sanding… A LOT OF SANDING.

After a few more hours of bodywork I primed the entire hood to get a good look at what else needed to be done. There were some minor issues, but nothing that needed to be fixed now. That will all be taken care of when I am prepping the rest of the car for paint later.

I’ll call this project finished. Nothing else needs to be done besides normal paint prep. It was a ton of work, but it turned out better than I expected.