Yo, U got beat by a Jetta????? OH, FOR SHAME!!!!!!!!! LOL!!!!
Yeah, people in the car is added weight, and will slow you down. And probably alot more than you might think. Especially when you consider we could be talking about 3 passengers equalling an additional 500 lbs. Thats almost 2.5 more lbs. per horsepower!
What kind of racing are we talking about? 1/4 drag or circuit style with corners and so fourth?
1/4 mile is more about reaction and launch. You have to figure out where the most controllable power is for the take off. You have to find out what rpm is the fastest launch to start from. Then you have to understand your car set up. If there isn't a whole lot of gain in the upper rpm range, like the last 1500 rpm before redline, then shift!!!! Your wasting time by having the car go through that part of the rev band before going into the next gear. So just as the car starts to approach that spot, back your foot off the throttle and let the car shift, then press the gas pedal to the floor again. ( Or use the paddle shifter on the steering wheel.) The faster you can get thru the gears, ultimately the faster you can get the car going. If you practice, listen to the car. Get to know when the car "sounds" like it's going faster than it really is. And learn to shift then. I've actually found that the IS 300 has so much torque, that if you shift the car at about 4000 rpm, it will actually get to fifth faster and the car will stay in the most powerful area of the rev band longer. So it's better to slowly press the gas pedal further as you go thru the gears rather than just slamming the gas to the floor. In other words , try following the speed of the car with the gas pedal.
Circuit racing is about setting up for the corners. Knowing your entry angles and speed, transitioning smoothly thru the apex and being in the right gear for the exit, and holding the drift back to the outside. ( I love this kind of racing.) This could be a whole book by itself.