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Radium Fuel Rails

cbrtrx

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Factory line comes into the rail on the driver side, then travels through the rail and through the crossover solid line to the passenger side rail.
This set up feeds from the factory line and splits into the back side of each rail. Passenger side theoretically speaking should get fed at the same time as the driver side rail. It's definitely better. Whether it makes any difference or not though is another story.
Keep in mind now the DI which uses a good bit of fuel is fed directly from one rail and right before the farthest away injector so actually as they route it it's worse then stock. If pressure drops then that front most injector is starved.
 
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Pistol_91

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Keep in mind now the DI which uses a good bit of fuel is fed directly from one rail and right before the farthest away injector so actually as they route it it's worse then stock. If pressure drops then that front most injector is starved.
Stock also does the same though. The fuel has a shorter path to the passenger rail with the radium set up though with the Y. So to me the stock is the weakest set up for that injector. An added crossover in the front of the rails should help keep that injector fueled though. You're referring to the front passenger injector correct? Do we know which cylinder that is?
 

cbrtrx

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Stock also does the same though. The fuel has a shorter path to the passenger rail with the radium set up though with the Y. So to me the stock is the weakest set up for that injector. An added crossover in the front of the rails should help keep that injector fueled though. You're referring to the front passenger injector correct? Do we know which cylinder that is?
Stock is not the same, the stock gen 3 rail has the dedicated main line to the DI nipple it does not feed off of one fuel rail. So stock the main feed line tees off and feeds both rails slightly offset from the middle and then the main line continues over to the DI. The bottle neck in that setup is the small crossover T branch to the rails that needs to feed 8 port injectors. The volume in the stock rails is plenty but at higher rpms it's limited by the tiny crossover so pressure drops off in the rails fast.

Now the way radium wants you to set it up as a deadhead the drivers rail will feed 4 injectors and the passenger rail basically feeds the other 12. That's why the crossover is important, without it when pressure drops the number 1 port injector (passenger front) will be starved first. The DI nipple is right before that injector and it uses enough fuel to feed 8 more. Even worse the pressure sensor is in the driver side rail so the actual passenger side rail past the Di would actually be a little lower pressure then that sensor is reading until the pressure differential between them is the same.

Bottom line on e85 and 750 plus rwhp having it setup like that can be risky. If your wot fuel pressure is rock solid then you'd be ok be most likely it will drop some. At wot you'll see your fuel trims adding a good amount to the passenger bank to try to compensate. One rail basically feeding 12 injectors is going to tax that one bank much more then the other rail only feeding 4.

If the fuel trims and fuel pressure and lambda at wot are rock solid then you can leave it. I'd still add a crossover though it hurts nothing and can only help balance a very unbalanced setup.
 
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Pistol_91

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I must have looked at the stock rail set up wrong then. Just going off memory. I didn't realize it was a direct line to the DI nipple. I thought it traveled through the passenger rail to get there like the radium set up is. I'll check it out when I get home. I do recall 2 hard lines going across instead of 1 so that second one I'm assuming going to the DI nipple. Never really noticed it. Like I said going off memory.
 

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Pistol_91

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I googled a pic I see what you're saying now. It's basically a direct line to the DI but splits in the middle of the cross over and splits again and goes to both rails. So yeah the radium set up without the crossover seems like it would be a much worse set up.
 

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So I self admittedly don’t know a lot about gen 3 DI, but for anything else, I don’t see how the Y manifold feeding each rail is a weakness nor that any injector on the rail would be neglected. And that’s why I opted for the dampers, which would accomplish anything a cross over or balance line would. My $0.02 for a non DI engine that is.
 

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Now it makes more sense to me after seeing this diagram.

IMG_7340.webp


IMG_7341.webp
 
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Pistol_91

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I got all of it together tonight. No time to start it or anything, I'll do that another day. I'm not going to lie I'm not very impressed with the routing of everything. The 90 degree right off the main line and just where the Y fitting is at. I think it's stupid... Lol.
I don't know why they couldn't give you a 12-inch hose from the main fitting to the Y and have it near the back of the manifold and have 2 evenly measured lines teeing off to one side and one to another. I don't get why they designed the Y fitting to be so close to the main line connector and on a 90 degree turn at that. Liquid doesn't like to flow through 90 degree turns, neither does air, or electricity.
 

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cbrtrx

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I got all of it together tonight. No time to start it or anything, I'll do that another day. I'm not going to lie I'm not very impressed with the routing of everything. The 90 degree right off the main line and just where the Y fitting is at. I think it's stupid... Lol.
I don't know why they couldn't give you a 12-inch hose from the main fitting to the Y and have it near the back of the manifold and have 2 evenly measured lines teeing off to one side and one to another. I don't get why they designed the Y fitting to be so close to the main line connector and on a 90 degree turn at that. Liquid doesn't like to flow through 90 degree turns, neither does air, or electricity.
Yeah their install kit is garbage, dosen't even look good.
 

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neither does air
Not quite. When air flows through a pipe and encounters a bend, it experiences something called "flow separation." This means that the air near the outside of the bend tends to separate from the wall and form a zone of recirculating flow, known as a "separation bubble." The size and shape of this separation bubble depends on the angle of the bend. For a 30° bend, the separation bubble is relatively small and doesn't significantly disrupt the flow of air. However, as the angle of the bend increases, the size of the separation bubble increases, and it begins to block more of the airflow. At a 90° bend, the separation bubble reaches its maximum size, completely blocking the inner half of the bend. This causes the airflow to detach from the inner wall of the bend and form a tight spiral, known as a "Dean vortex." While this may seem counterintuitive, the Dean vortex actually helps to improve airflow through the bend, as it reduces the pressure losses associated with flow separation. As a result, air can flow more smoothly through a 90° bend than through a 30° bend, despite the sharper angle.
 
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Pistol_91

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Not quite. When air flows through a pipe and encounters a bend, it experiences something called "flow separation." This means that the air near the outside of the bend tends to separate from the wall and form a zone of recirculating flow, known as a "separation bubble." The size and shape of this separation bubble depends on the angle of the bend. For a 30° bend, the separation bubble is relatively small and doesn't significantly disrupt the flow of air. However, as the angle of the bend increases, the size of the separation bubble increases, and it begins to block more of the airflow. At a 90° bend, the separation bubble reaches its maximum size, completely blocking the inner half of the bend. This causes the airflow to detach from the inner wall of the bend and form a tight spiral, known as a "Dean vortex." While this may seem counterintuitive, the Dean vortex actually helps to improve airflow through the bend, as it reduces the pressure losses associated with flow separation. As a result, air can flow more smoothly through a 90° bend than through a 30° bend, despite the sharper angle.
Whatever you say, nerd.
 
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Pistol_91

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Yeah their install kit is garbage, dosen't even look good.
I just ordered a bunch more different shit so I can make this look and hopefully flow a bit better. After I was done, I was staring at it and said, "for the money, this looks like shit". Seems to me like minimum effort was used. Oh well.
 
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Pistol_91

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I got everything buttoned up, ran my own lines. Used a few parts from the kit. Everything seems good though, no leaks. Pressure looks good on logs still so everything seems normal, Except, I can now hear the DI injectors or just the pump itself inside the car. Its WAY louder. During idle is when I hear it. Very noisy now.
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