Nissan Brings GT-R Bling To Altima Production

Diamonds are forever.

Matthew Guy By: Matthew Guy April 26, 2019

Well, industrial diamonds, at least. But diamonds are diamonds, and a special manufacturing technique usually reserved for supercars has found its way into the 2.5-litre engine of Nissan’s Altima sedan

The company uses something called a mirror bore process to reduce friction and improve efficiency. First used in GT-R production, it helps engines run smoothly by eliminating the need for cylinder liners. Mirror bore equipment has been added to the Altima’s production line in Tennessee, marking the highest volume application within Nissan. How high a volume? The plant is capable of churning out an engine every 19 seconds, working out to approximately 1.4 million of the things a year.

The mirror bore process sounds like something that would happen inside Studio 54 but actually involves spraying and polishing the cylindrical space in which a piston moves. During the spraying phase, sparks fly as charged metal wire is blown using gas to atomize the material and coat the inside of the cylinders. The thickness of the coating only needs to be about twice that of a human hair.

In the second stage, a special drill bit is used containing tiny bits of diamonds that were unsuitable for snazzy jewelry. This is why they’re called industrial diamonds. The bit is spun at dizzying speeds inside the cylinder to polish the metal until shiny and smooth, giving the process its mirror bore name and the cylinder walls a reflective surface.

Diamond Polishing Tip

“Technology like the mirror bore process only makes sense for Nissan if we can offer it to as many customers as possible,” said Jay Boyte, director of engineering at Decherd Powertrain Plant, Nissan North America. “The end result is an innovative and efficient engine made with manufacturing technology usually not available at this volume or price point,” added Boyte.

The current Altima sedan was launched late last year and comes standard with all-wheel drive in Canada. Features like ProPilot Assist keep it on the leading edge of technology, fighting for a toehold in a marketplace that prefers crossovers and SUVs. The diamond-fettled 2.5L engine is the sole powertrain option for 2019, making 182 horsepower. Prices for volume models start at $27,998 in Canada for an all-wheel drive S model and top out at $34,998 in Premium trim. A limited edition ONE model, of which there will only be 250, gets some unique jewelry and a $35,998 price tag.