Be careful with performance chips
QUESTION: I’ve seen the ads for performance/mileage-enhancing chips and can’t help wondering: If they’re such magic why are the vehicle manufacturers not using the technology? They would surely want to squeeze the most out a gallon of gas, wouldn’t they? I have a 2011 Chevy 2500 van with the small V-8 and am thinking about buying a unit.
ANSWER: The auto manufacturers with the best fuel economy have an advantage in sales, so you can be assured they’re trying to get the best they can at a reasonable cost of production. It’s possible to get even better fuel economy, but it would make the cost of a vehicle so high that no one would buy it.
Manufacturers also have to meet many regulations with new vehicles, one of them being emissions standards. Simply put, if the vehicle doesn’t meet emission standards, it can’t be sold. The performance chips you have been looking at are built for the aftermarket and don’t have to meet emissions standards. In fact, many of them will state that they are for “off-road use only”, so they don’t have to meet the standards and can tune the engine for better fuel economy even though emissions may be higher.
Typically, performance chips modify the ignition timing curve to give more spark advance and change the amount of fuel delivery under load and cruise to give better fuel economy and performance. Some of these chips will also turn off some of the emission devices, although that doesn’t really increase performance and may modify transmission shift feel and rpm points for a crisper shift.
I know several vehicle owners who have used performance chips with good re- sults, but be aware that using one of these aftermarket chips or programs will void any powertrain warranty you have on the vehicle.
Jim Kerr is a mechanic, instructor of automotive technology, freelance journalist and member of the Automobile Journalists’ Association of Canada.