Difficulty: Moderately Easy
Things You’ll Need:
Step1
First, make your car as light as possible. Even 50 extra pounds can noticeably slow you down. And guess what weighs almost 50 pounds. The spare tire and scissors jack that's probably in your trunk. So definitely take that out. It's the easiest to remove, significantly heavy item that most cars have. And while you're at it, if you have a lift up, completely loose floor in your trunk covering the spare tire, take that out too. That usually weighs at least 10 pounds. If you can take out seats, obviously do that too. If your passenger seat is only held in by bolts, usually 4 of them, just undo them and take the whole seat out. That and the tire could take off well over 100 pounds off. Even small things like taking out glove compartment items and cleaning out your trunk and back seat will help. And finally, make sure your gas tank is around half full. Any less and the fuel pump may not be able to provide 100% flow and any more isn't worth the extra weight. I've even seen people race without their hood. That's almost a hundred pounds of solid metal on some cars and is easily removed by taking off a couple bolts. Plus, that provides great engine cooling. Just make sure it's not raining.
Step2
Okay, so I said you won't have to spend money on upgrades but I have to mention this one because it's so simple and cheap. Take out your air filter and replace it with a high flow K&N cotton one. It usually gives you 5 extra horsepower and makes a noticeable difference in acceleration, especially for cars under 200 horsepower. Most filters are around $55 and take about 2 minutes tops to install. Plus, it can help your gas mileage slightly so why not. And it lasts at least 20,000 miles so it lasts far longer than paper ones and the cost is about equal over time if you calculate it.
Step3
Make sure your tires are properly inflated. This will help prevent power loss as well as help your tires maintain traction better. Don't use the PSI rating on the side of the tire though because each car is different due to weight. Plus that's a maximum safe PSI, not a recommended driving PSI. Look in your manual or online for the actual PSI your car's tires should have and make sure all your tires have exactly that pressure. You might want to buy a tire pressure gauge at a store to check it accurately. They're only about $2-3.
Step4
A final large advantage that may cut whole seconds off your quarter mile time is to rev the engine before taking off. If you have a tachometer (aka RPM gauge), hold it at around 2000 RPM with one foot hard against the brake and one on the gas. Then as soon as the flag waves or the hand drops or the green light comes on or whatever other signal you're using, just take your foot off the brake and as soon as you feel the car start to move forward, floor it. If you notice that flooring it causes your automatic transmission to shift inefficiently, then let off a little before it shifts in future races. You can experiment with different starting RPMs depending on the temperature and your tires and vehicle weight. The best take off will have a brief tire squeal. Too high of an RPM will cause the tires to spin without any traction for too long and waste time and too low of an RPM will cause you to take off without all the power you could have. To cheat the RPM limit a little, some people purposely hold the brake and rev up to 3000+ RPM to spin the tires for a few seconds right before pulling up to the starting line because hot tires grip better and that heats them up.
Step5
With all these simple tips, you can make sure your car races as fast as possible without actually spending money on serious upgrades.
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