Staged injection is not uncommon outside of professional motorsports realm these days, however the use for it on the 1989 Sauber-Mercedes C9 Le Mans winner was a little different to what most of us are now used to in the aftermarket industry.
The 800HP M119 5L V8 turbocharged Group C endurance racing Sauber-Mercedes C9 technically would have been fine with just a single injector, however, to make the most of the technology available at the time it was instead fitted with two 440cc injectors per cylinder allowing the engineers to take advantage of finer control over the fuel spray pattern and injection timing with economy in mind.
These days with advances in both injector and ECU technology it is more common to have a primary and secondary injector of different sizes allowing for fine control over idle and low load situation via a smaller injector, and the second larger injector to kick in as the engines fuel demands increase.
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