For those of you wondering how consistent the Unichip tuning is, take a look at these results from a 2001 Ford F150 SVT Lightning and remember that we did a similar exercise in a previous article with a Lexus SC400. Once again, the Unichip rules. In this case, we were dealing with a heavily modified car: k&n cone type air filter, crank pulley, headers, total performance ported heads, and throttle body.
As you may remember, the Lexus was stock except for a K&N air filter. That car picked up 27 RWHP and TRQ which is pretty impressive for a single mod on a stock car. This truck, however, had some serious work done already. So, the question is: do you get as much out of the Unichip when you have a modified car? Yes, in a big way. In many instances you actually get more out of tuning when the car is modified. With modified cars, the stock computer is often extremely off because it was not designed for the modifications that were done. Take a look at the before and after on this truck. We are looking at an average of 30 RWHP and 34 RWTRQ. And in the usual Unichip style, you get this increase across the whole RPM band. That is the beauty of a dyno tuned chip. It is tweaked exactly for your car and your whole curve goes up.
An interesting thing to note was that the stock A/F ratio wasn’t too far off for this car (compared to some that are way off). But regardless, a little tweaking can go a long way especially when combined with timing changes and all the other modifications. The stock computer program has to work under all conditions, and in this case all conditions means bad weather, bad gas, and changing altitude. Most of us can control the bad gas and changing altitude, e.g. we can pick 93 octane and live in the same place. This means that a car with a stock computer program capable of dealing with 87 octane and changing altitude can be changed to a 93 octane advance and optimum A/F ratio. But again, the key thing here is that you step through the entire RPM range and tweak these values until your engine puts out the most power.
A little aside here. Some may be wondering what the deal is with A/F ratio. An A/F ratio of 13:1 means that we are giving the engine 13 parts of air to one part of fuel. So, what is a part exactly? The A/F ratio is specified in weight not volume so it means 13 kilograms of air per 1 kilogram of fuel. The problem is that the engine does things in volume and the volume changes over altitude. For example, at sea level a kilogram of air is about 760 liters so we need 13*760=9880 liters. At 1500 meters 1 kilogram of air is about 900 liters, so now we need 21580 liters of air. All this needs to be taken into account which is the purpose, for example, of the mass airflow sensor. It measures the mass and sends the number to the ECU. The ECU then looks at its maps and decides how much fuel to give. The idea with tuning a car is giving the ECU a better map to use for A/F and timing.
You never know exactly how a particular car setup will respond to tuning until you actually do it. Another thing to remember is that the chip helps drivability and fuel efficiency when in normal driving situations. For example, you usually want to tune your wide open throttle (WOT) maps for maximum performance and your part throttle maps for drivability and fuel efficiency. Whatever the case, the Unichip gives you the flexibility to do it however you want, and regardless of whether the car is modified or not, you know you will get some serious gains.