The Mustang Source - Ford Mustang Forums

The Mustang Source - Ford Mustang Forums (https://themustangsource.com/forums/)
-   5.0L GT Modifications (https://themustangsource.com/forums/f800/)
-   -   5.0 direct injection (https://themustangsource.com/forums/f800/5-0-direct-injection-534958/)

Kestral 1/10/15 08:27 PM

5.0 direct injection
 
How much more power would the 5.0 V8 coyote make if and or when Ford decides to direct inject the motor?

5LHO 1/11/15 10:33 AM

Not necessarily any. Direct injection has been around sine the 1930s but it isn't a power adder. It offers more precision in fuel tuning but requires a host of supporting adaptations to make it work, like a massive mechanical fuel pump, especially in a large displacement V8.

The advantage is that you can inject EXACTLY the right amount of fuel at exactly the right time. right into the chamber. Thus you don't have to mechanically compensate for injector delay, fuel dropout or engine vacuum conditions in your tuning. It makes ridiculously powerful cars easy to drive.

The port injection setup in this car is as close to perfected as you can get with that setup. The injectors are inches from the intake valves, the whole Copperhead fueling setup is fantastically sophisticated, running closed loop all the time, etc. It's about as good as it will get and is relatively cheaply and easily modified for extreme duty should the owner want that.

DI will come for this platform in time; the engine was designed for it but, the plug was pulled as a cost saving measure, since the engine could reach its power, fuel economy and emissions goals with the cheaper PI setup.

Joeywhat 1/11/15 10:45 AM

DI seems to be used more for fuel economy in today's engines...at least from what I've seen.

lakeguy77 1/11/15 12:29 PM

As previously said, DI doesn't "make" power. It's advantages lie in precision. With port injection, you'll get a bit of a "pooling" effect of fuel on surfaces outside the combustion chamber (I want to say the engineering calculation for this effect is referred to as Tau, but that might not be right, didn't bother googling before typing :) ). Eventually that pooling is pulled into the combustion chamber, but it essentially leaves a margin of error, because not all the fuel the injector sprays goes directly in, and when the injector shuts off, there's still fuel to pull in. With direct injection, whatever leaves the injector, is in the combustion chamber, so it's a very exact calculation and you don't have to build in as much margin for error. This lets you tune your fuel and timing tables closer to the limits of knock and hit your fuelling and timing targets very accurately without problems. That's where the extra power and fuel economy comes from. So it essentially becomes a cost-benefit analysis, as DI is much more expensive for both the manufacturer and the end user.

The above is dramatically over simplified but hopefully illustrates the point.

Kestral 1/11/15 01:26 PM

Wow great in depth answer good stuff thanks all.

88lx50 1/16/15 05:59 AM

I am pretty sure you can run ridiculously high compression with DI

tom281 1/16/15 06:31 AM

Yep and makes moar powoar

lakeguy77 1/16/15 10:31 AM


Originally Posted by 88lx50 (Post 6888454)
I am pretty sure you can run ridiculously high compression with DI

Again, as a result of the precision of DI fuelling. You can run boost on regular fuel, high compression and boost, you can run incredibly lean at cruise for economy.....


All times are GMT -6. The time now is 06:00 AM.


© 2024 MH Sub I, LLC dba Internet Brands