If you are looking to invest in equipment to get faster the best things to buy assuming that you don't have them already are as follows.
1. Clip on aero bars and enough training time to get comfortable with them
2. A decent clipless setup(pedals and shoes)

The benefits of aerobars are obvious but if you've never used clipless pedals I can't recommend them highly enough for racing. A decent setup will last you a long time and if you do get more into cycling you can easily transfer the pedals to a new bike.