Intelligent Performance

Anyone can purchase a bunch of bolt on MODS and make their car faster. What if you don't have that much money to spend on the car or the car is like a Chevy Aveo and doesn't have much aftermarket support? Also, how do you know what MODS will give you the most bang for the buck? This article will focus on the MODS most people can do, without spending lots of hard earned cash and still get some great results.

Since the motor is basically a big air pump, the first thing I will work on is the breathing. Increasing the volumetric efficiency on a newer car does not have the results it would on say an 80's car, but it's still the best place to start. The goal is by allowing the engine to breath more easily, it will breath more air and hence, more power and better fuel economy. 

Notes regarding performance testing: Since the car is a 5 speed and difficult to reproduce 0-60 runs, I will leave those out of my performance test. Instead I will use industry standard 30-50 in 2nd gear to test high end power (horsepower) and 50-70 in 4th to test power down in the lower rev range (torque). 

I had actually done some performance testing the day I purchased the car, however was too slow to post the information and since lost the paper it was written on. This is too bad as I now have nothing to monitor my first mod results other than an unreliable "butt dyno."

Air Intake: The first thing to do is look at the stock system and see where there might be any obvious points of improvement. While looking over the Aveo, I noticed an air box muffler prior to the air box, wrinkled intake line, and a 2" diameter tube going into the intake box. I'll try to address all of these to find where the most restrictions are. Another way to check would be making a "manometer" which would measure the pressure drop in inches of water. This can be made with a 20 oz soda bottle, clear tube, wooden dowel, and some food coloring. 

Air Box: The first MOD was done within a few days of buying the car new. Simply remove the intake muffler that resides in the fender. I then went one step further and drilled out the opening to 2.5". Still unsatisfied, I then cut the rubber flare off the end of the intake muffler and hot glued it to the opening that goes from the air box to the throttle body. This flare smoothes out the airflow and can actually increase it by as much as 14%, it also makes the car a little more quiet as the resonance is decreased.  It's important to retain the stock position when drawing in the air since the air in the fender is much cooler than that in the engine bay. For every 4 degrees C, that the air is cooler, that is about a 1% power increase. Though the results are not very good, the sound was much better, but still not well enough. Not bad for a free MOD that just took a little time. 

Air Fuel Ratio Meter: To monitor the fuel ratios after installing the new rear muffler, an air/fuel ratio meter has been installed.  This is the only picture I have of it. You can see it's the small box under the stereo with the green light. I'll update this pic later. 

So far the performance mods have been kept under $150 and have been quite simple to do. The next mod is a little more advanced. I will be using an ebay header designed for a Honda B16 and modifying it to work with the Aveo. 

I believe headers would help considerably on this car.