Yea, the little NOS shot will be about worthless unless your racing. The thing you buy a at walmart comes with co2 not NOS, NOS is used in creme whippers generally in smaller cans you can use in a tire inflator with a spacer. Get a billet rod and flywheel, some stiffer valve springs, and remove the governor, after that (around $200 in parts) you will see speed gains as you can rev the engine much higher. Best small free gain is to gut the muffler it will be louder but more powerful.