Maximizing the amount of RX antenna you have in line with your transmitter antenna is the best way to get maximum range. With 2.4Ghz radios, the two antennae must be parallel for maximum signal exposure and clarity. That being said, most tracks are small enough that the amount you have vertical in your car now is certainly sufficient so long as you keep your Tx antenna vertical as well via the swivel joint. "Exposed" antenna has nothing to do with it. Most parts on an RC car are radio translucent anyway.