Firewalls N' Grommets

Don't know the exact answer, but use common sense: If it's a rubber bung/plug, just pop rivet a piece or beer can or something with more heat resistance over that whole. If it's a grommet to shield the wires from getting cut by the metal, you're more than probably ok. A "sealed" firewall is to prevent flame and hot/burning fluids from entering the passenger cabin. Think: "If my car were standing on it's rear bumper and the engine bay were leaking fluid and on fire, what holes and gaps would I wish were sealed up better before I found myself in this situation."

If the grommets are stock original to the firewall then they should be O.K. Most grommets have some kind of hole for wires to pass through, make sure yours don't or you will fail. Like all other comments beer cans, spare bolts, even steel tape helps. We had an inspector fail us because we had holes in our front wall, even though there is no engine in the front of an MR2. We explained this to him, his comment "put some duct tape on it and I will pass it". My comment "Duct tape it is", no real reason to argue when I really want to race.