I'd be pretty surprised to find out there were horsepower gains just from converting from common rail to mechanical injection. To the contrary, common rail injection has two huge power-making advantages: 1) the ability to precisely deliver exactly the amount of fuel needed for a complete burn and 2) drastically improved fuel atomisation due to the very high pressure of the injection rail and geometry of the electronically controlled nozzles.
You see, a mechanical nozzle requires a certain amount of fuel pressure to open it, and so the p-pump creates a pulse in fuel pressure to the nozzle in order to let fuel into the combustion chamber. That means that at the beginning and end of the injection, as the nozzle opens and then again as it closes, there's a little sputter of poorly atomized fuel. Furthermore, the way the fuel volume is controlled is by increasing or decreasing the pressure. So there's a difference in engine efficiency depending on RPM.
In common rail injection, the fuel rail is at a constant, very high pressure. A solenoid opens and closes the nozzle extremely quickly, and since the pressure is constant during the whole time the nozzle is open, the fuel enters the chamber perfectly atomized and in a spray pattern engineered to optimize the shape of the flame front. The result is more power, better fuel economy, and lower emissions -- all at the same time.
The problem is, it's all controlled by a computer... which is programmed by an egghead at the Dodge factory, and then closed up tight. You can't get in. So you can buy a power chip, and there are things you can do with some of the sensors to "fool" the computer into giving you more power, but your options are limited.
Whereas with a p-pump, even though your starting point is lower on the power and economy scales, any dumbass with a pair of pliers can come up with ways to change the way it behaves. And, as it turns out, some folks are pretty darn good at figgerin out how to get more RPMs out of the engine, more fuel volume, etc. That's where you get the power from.
I'm glad you asked this question, because I'm really hoping there will turn up some fellas who have made this modification to their 24V engine and can shed light on how hard it was, how well it works, etc. Because 24 valves is great, but being able to drive underwater and not be stopped by EMPs is pretty cool too, I think...
You see, a mechanical nozzle requires a certain amount of fuel pressure to open it, and so the p-pump creates a pulse in fuel pressure to the nozzle in order to let fuel into the combustion chamber. That means that at the beginning and end of the injection, as the nozzle opens and then again as it closes, there's a little sputter of poorly atomized fuel. Furthermore, the way the fuel volume is controlled is by increasing or decreasing the pressure. So there's a difference in engine efficiency depending on RPM.
In common rail injection, the fuel rail is at a constant, very high pressure. A solenoid opens and closes the nozzle extremely quickly, and since the pressure is constant during the whole time the nozzle is open, the fuel enters the chamber perfectly atomized and in a spray pattern engineered to optimize the shape of the flame front. The result is more power, better fuel economy, and lower emissions -- all at the same time.
The problem is, it's all controlled by a computer... which is programmed by an egghead at the Dodge factory, and then closed up tight. You can't get in. So you can buy a power chip, and there are things you can do with some of the sensors to "fool" the computer into giving you more power, but your options are limited.
Whereas with a p-pump, even though your starting point is lower on the power and economy scales, any dumbass with a pair of pliers can come up with ways to change the way it behaves. And, as it turns out, some folks are pretty darn good at figgerin out how to get more RPMs out of the engine, more fuel volume, etc. That's where you get the power from.
I'm glad you asked this question, because I'm really hoping there will turn up some fellas who have made this modification to their 24V engine and can shed light on how hard it was, how well it works, etc. Because 24 valves is great, but being able to drive underwater and not be stopped by EMPs is pretty cool too, I think...
arty018:
