You'll probably want to seal the top of the airbox but not a huge deal.Engine perspective: Air entering the grill is ducted to the air box, at WOT the fresh air will be ingested into the engine, at idle/cruise the unused air will go out the vent, sealing the airbox will net some tiny amount of...

Thanks for the kind words with the Race Louvers. In case this hasn't been mentioned AJ and I have taken things to a whole new level.. https://trackaeroconsulting.com/our-portfolio/

plenty of room, but the fan shroud has to go. https://racelouvers.com/content/Race-Louvers-Fan-Shroud-Wind-Tunnel-Data.pdf

Yes there are prefilters that are repel water while allowing air to pass, they are popular in the offroad community, and they work well. However in the GT350s case, the top seal that seals the airbox to the hood is restrictive to airflow out of the louvers so its best to remove the seal and put...

Yes, since the cone filter is directly under the louver you will need a cover for the top of the airbox.

Some more wind tunnel data. https://racelouvers.com/content/Race-Louvers-GT350-GT4-Wind-Tunnel-Data.pdf

We have wind tunnel tested many hood vent designs and hoods and have data on our website. Most hoods and hood vents on the market are cosmetic and have little functionality, ours are top notch. www.racelouvers.com

Also for those into the GT4 look, our Race Louvers GT4 style extractor is available for the GT350 seen in the above video, but we have other sizes that fit the '94-98 mustangs, '99-04 mustangs, '05-09 mustangs, '15-17 mustang base models and universal fitments for other applications.

Heres Trackspec vs Race Louvers: https://racelouvers.com/content/Race-Louvers-Wicker-Gurney-Flap-Raised-Louver-Wind-Tunnel-Data.pdf Heres Tiger vs Race Louvers: https://racelouvers.com/content/Race-Louvers-Mustang-Hood-Shootout-Wind-Tunnel-Data.pdfBasically tiger and trackspec operate about...

I would recommend our RT Track Trim center and RT sides. If you want near flush mount for aesthetic reason then the RS Street Trim. https://racelouvers.com/hood-louver-trim-photos/

The biggest issue with side hood vents for the 15-17s is the front half of the vent is forward of the radiator including trackspecs and we know from wind tunnel testing venting a hood needs to be behind the radiator for good airflow thru the rad. Our Race Louver kits have a blank panel built...

Hood and fender venting is mainly for cooling however it does add some DF. Good extraction allows aero parts ie a splitter to work better. So adding venting on a non aero car adds cooling and a little DF, adding venting on an aero car adds cooling and a bunch of DF. Plenty of data here...

So we have this center kit for the 99-04 mustangs which should be available shortly, it is meant to sit on top of the hoods main surface covering the entire center recessed area, blanker panel in front and rear positions louvers right behind the radiator for optimum performance, louver blades...

Ah, excellent question. Some back round, first keep in mind cooling is truly about airflow thru your rad, oil and intercoolers up front. Relative to engine bay pressure, the pressure on top of most vehicle hoods can be broke down into 3 areas, the front 1/3 which is low pressure, the middle 1/3...

Bigger how? The width of most of our kits is as big as the hood body lines will allow.