It is already heating up here (Arizona) and I'm thinking of switching to an STI hood scoop as it supposedly has 1/3 more airflow than the stocker 02 scoop. Does an 02-03 STI hood scoop work with the stock intercooler splitter for the WRX? Will everything seal correctly if the scoop is the only part I change out? Does the STI scoop flex as badly as everyone says it does, at highway speeds?

It works, but it would work better with an sti splitter. Everything will seal correctly.I have never seen my sti hoodscoop flex on the freeway.

I have a 03 wrx with sti hoodscoop i have had my car at 120mph+ scoop didnt flex and it seals properly..

You dont need the STi splitter unless you have a larger IC. I have an STi hoodscoop with the original IC and splitter on my 02, it seals fine and no flex.

I think the bigger hood scoop is a good upgrade, more air flow and better looks. Cant go wrong IMO

Thanks guys. Now only concern is matching the paint color; my PSM 02 WRX has been baking in Arizona sun for 3 years, it won't match factory PSM paint...

In September I completed an install of an STI hood scoop and custom air duct on my 03 WRX. I teach engineering classes at a vocational school in Maryland. I cut the stock duct-work off and fabricated new taller duct-work. If you use the stock duct you are not really changing the flow of air to the intercooler because the duct is what directs the air. The air that moves above the duct is trapped between the duct and the scoop, which is what causes the cheap STI knock off hood scoops to blow off the car. I have the sheet metal drawings if any one wants them (I use the factory duct base and attach a new taller duct to it). I spent a lot of time with R & D with the duct using CAD software and making prototypes to ensure proper fit.

I thought the duct would be easy to make but upon inspection of the stock duct, the duct is curved and not symmetrical because part of the duct channels air back to the back of the engine bay to help lower the temperature around the turbo. I noticed a slight difference after I installed it but I think this was due to driving around for a while without a duct as I was developing the new duct work.

I plan on getting the genuine JDM STI scoop, so I'm not concerned about it blowing off. I don't have access to the kind of equipment I'd need to fabricate a custom duct, but that would be cool. As of now I've got no plans to upgrade the intercooler itself (I'm done with power mods for the car) and thus the STI splitter, if I got one, wouldn't seal up with the existing intercooler. The primary reason I want a taller hood scoop is that abou 80% of my driving is highway, and I've heard from several people (one of whom is an open-class racer with quite a few trophies on his shelf and a WICKED GC8) that at speeds above 40mph the air just skips right over the stock hood scoop for the 02-03 WRX, splitter or no splitter. I'm not on boost much in the highway, but when I do need the power I like to have it -- and the performance of the car clearly suffers when it gets hot here, even with my existing power mods.

That's cool though, sounds like a fun project. Just need to find someone with a C&C machine to cut it for me :)

no cnc needed just sheet metal and snips