You can add a waxing agent or other things, however the BEST thing that I found with my painting projects is a product called DURATECH. This stuff makes the Gell shoot out MUCH better and also will gloss up better. In a engine bay you can probably get away with just getting some agressive compound and buffing it out. With this product there is NO need to use any waxing agent or anything on top. It makes the gell harder and gloss more Good luck.