Recently, Mahle Motorsport partnered with Extreme Turbo Systems (ETS) to set a new record with the Nissan GT-R for the quickest quarter-mile and the fastest standing half-mile. To accomplish this, the GT-R was equipped with Mahle pistons designed for power, performance, and durability.
“You have to change the pistons if you are going to do anything aggressive,” said Trey McFarland, marketing manager for Mahle Motorsport, during the 2018 SEMA Show, held in Las Vegas, Nevada.
“When you start making a lot of power it’s not uncommon to damage one piston and then if it is a custom set you’re in trouble,” McFarland said. He added that much of what Mahle learned from ETS was applied to the pistons sold off the shelf, readily available for an affordable price.
Consequently, the piston is capable of handling power levels over 1,500 horsepower and able to control boost pressures exceeding 65 psi.
According to McFarland, the production process starts with ultra-strong, low drag, lightweight, 2618 alloy Mahle slipper skirt forging. The forging is precision machined to exacting tolerances on purpose-built equipment manufactured by Mahle specifically designed for piston production.
The pistons are then coated with a phosphate dry lubricant to guard against galling in the pin bores and add lubricity in the second and third ring grooves. The top ring groove is hard anodized to protect against micro-welding ensuring optimum ring seal over the life of the engine.
Finally, the piston skirts are treated with Mahle’s proprietary Grafal anti-friction coating. In addition to lowering frictional drag, Grafal has a cushioning property that dramatically reduces wear for both the piston and the bore as well as a substantial reduction in noise.
“We have single pistons on the shelf, and we can ship them out the same day. This year we added a stroker piston for the GT-R, taking them from the 3.8- to a 4.1-liter,” McFarland said.
Other supported applications include Hemi, LS, Ford, and BMW engines. Moving forward, McFarland says European applications will get more focus, specifically Volkswagen, Mercedes AMG, and Porsche.
According to McFarland, most people who want a “custom piston” really want an off-the-shelf piston with slight modifications, like a deeper dish or a pocket change. McFarland said the equipment Mahle uses for custom pistons is tailed around race teams that are planning on using the pistons a few months out, “we have slowed down when it comes to the drag race market.”
“We are working on lines of more drag specific pistons for big block Chevy and LS that are typically power adder applications. We do a lot of drag racing now, but it crosses over from circle track or road racing, but it’s the power adder that we have been short on” McFarland said, adding they are currently working on power adder pistons now.
“When someone ends up with a Mahle part, they get something highly engineered with a lot of time spent on it. That is why we are not always the first ones to market. But what we put out is a good solid part that is overbuilt nine times out of ten.”
For more information on Mahle PowerPak Pistons, see Mahle Motorsport.