Quote:
Originally Posted by NeilBlanchard
Q: what is GDI?
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Gasoline Direct Injection. It's using gasoline like diesel. It allows for enormously high lean burn ratios(so far I think 65:1 on a sustainable ouput). Only downside is its a little more expensive and complicated than normal injection(outside the cyliner for FI and inside after compression for GDI).
The idea is you can compress tons more air and as it gets to the point its about to ignite you squirt a little fuel in and it cools the mixture by evaporating the gasoline. Repeat the process until you reach the point you want to ignite. You could inject no fuel and get it to ignition squirt alittle, compress a little more to maximum ( I think 5-6 degrees from Top Dead Center) and then ignite the hot very compressed air, tiny amount of fuel mixture.
Ford and GM both claim they have engines that are 30% and 20% more efficient respectively. The nuts and bolts are you run WOT all the time and just inject the amount of fuel needed for however much power you want.