Defying Expectations, No Matter the Challenge
Case Study: Engineering a single pump GDI solution for V6 and V8 engines
When you need a solution quickly, you want a versatile partner who can solve the problem, based on the unique task at hand. For decades, Stanadyne has approached some of the world’s most complicated fuel system challenges with a flexible product strategy that delivers custom fuel pump solutions.
Having access to cutting-edge technology is essential to stay ahead of the curve in the automotive industry – but it isn’t the only necessity. At Stanadyne, we understand that every engine manufacturer has unique requirements for their GDI applications, and frequently, tough challenges to overcome. That’s why Stanadyne works closely with customers to tailor customized solutions that solve the toughest challenges with innovative solutions. This approach combined with decades of experience gives you an award-winning strategy.
SP1250 GDI Pump
It was this strategy that helped Stanadyne forge a successful partnership with a well-known, global OEM. In 2004, Stanadyne was approached by this OEM to help them to develop a unique single-pump solution for their V6 and V8 engines.
To meet the fuel delivery requirements for engines of this size, most GDI systems use two high-pressure pumps. But for this customer, there were unique requirements that made it difficult to install a two-pump system without cost and efficiency ramifications.
Stanadyne embraced the challenge, and by 2013 launched the first single pump solution for high-displacement, high-horsepower applications on trucks and SUVs. The SP1250 not only met the displacement requirements of the engine but was designed with several features that exceeded the customer’s expectations for performance, including a patented floating plunger sleeve mount, a beehive spring design and the first generation of our QuietTechTM metering valve technology.
Our patented floating plunger sleeve mount isolates mounting loads and the plunger bore, which allows for low clearances between the plunger and sleeve. The plunger and sleeve are match fit to a clearance of less than 8 micron, which enables industry-leading volumetric efficiency and pressure rise rates at cranking for fast engine start times.
Another feature that was designed for the pump is a dual, or beehive, spring. An outer spring to handle tappet loads and a smaller inner spring to handle plunger return. Separating these spring loads led to a more robust pump due to the minimized plunger side loading and improved tolerance to spring out-of-squareness.
The SP1250 was also among the quietest pumps on the market at the time of its development thanks to our QuietTech package of technology. From the inlet valve to the control valve, the internal hydraulics of this pump were optimized to address radiated and transmitted noise.
In conjunction with this pump development, Stanadyne also developed a larger single-pump solution for high-performance engines up to 650 HP. The SP1550-200 uses similar design concepts as the SP1250-200 I, but delivers even higher output for powerful sportscars. The SP1550 can supply up to 1550 mm3 of fuel per engine revolution, making it the highest output GDI pump on the market.
Since its launch in 2013, more than 5 million SP1250 and SP1550 pumps have been manufactured, and both have proven to be among the most dependable fuel injection pumps in the world.
Stanadyne continues to raise the bar for fuel injection technology by continuously developing new ideas for the future of GDI pumps. The next generation of the SP1250 pump, which is scheduled to begin production this month, is engineered to be even lighter, quieter and more efficient than ever.