Besides having to have double the fuel injectors, is there any disadvantage to having BOTH port injection and GDI (gasoline direct injection) on the same car (dual injection)? This seems to be catching on, and is on the new gr corolla.
by BeaglePops7
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8 Comments
You can just call it “direct injection”. It’s like saying New York City. You can just call it New York.
The downside is complexity and cost, but the efficiency, performance, and lack of carbon build up is worth it
Just direct injection causes there to be carbon build up on the valves that require to be walnut blasted on routine intervals. Common on (08-10 turbo) CobaltSS and some versions of BMWs (335 comes to mind). Port injection helps with the build up. So not a disadvantage. Even with some bigger turbo cars that were direct injection factory they will add port injection for more fuel.
Biggest advantage is washing the backs of the intake valves, especially with all the PCV systems. From what I was told, the GR Supra has both, and I suppose they’d use the port injectors for adding the additional fuel needed in high boost applications – although I’ve never checked ProDemand for a proper operation… *things to do at lunch tomorrow…*
2013 GR86
One of my favorite parts of the BRZ is that however simple of a car it was, the engine was direct and port injected
That engine had a lot of flaws in practice, but on paper it was a pretty cool engine. 100hp/L and 50hp/cylinder and NA is still a pretty good metric for modern sports cars, not a whole lot does much better without forced induction
Really just cost and complexity. It’s a benefit though. It allows cars (like the RS3) to be efficient and powerful without worrying about carbon buildup. It also allows some cars to push more power when modified without running out of fueling.
Some tuners add port injection to a direkt injection engine to gain more power in combination with with other stuff like bigger turbos