Stock Fuel Pump Evaluation

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Here is what I have found about the factory Prelude fuel pump.
It works GREAT for non-turbo cars and it even worked good with the turbo up to 6psi with no intercooler. I ran my car with the stock pump for about 8 months without problems (as long as I kept the boost below 8psi). I also had the stock cat convertor in place. That restricted the exhaust enough that the turbo only made 6psi. Even when I turned the boost to 8psi, it did not seem to detonate with this setup.
Then I installed a high-flow 2.5 inch cat. WOW! Boost instantly jumped to 7psi with a peak of 8psi. I still had no intercooler. With it setup like this, it was running dangerously lean. I have an Air/Fuel Ratio meter in the car and under full throttle, it went completely lean. Now that I had this extra boost and exhaust flow, I needed more fuel.
It just so happens that I had an in-line Bosch fuel pump on my shelf. I bought it from a guy that had a used DRAG turbo kit that he was parting out. I had heard good things about this pump and the price was only $90 so I bought it. I had planned on putting it on my other Prelude but I took it apart before I ever got to install the pump, so it sat on my shelf for almost a full year.
I installed the pump in-line and I left the stock fuel pump hooked up in the gas tank. I put the Bosch pump under the hood in the hose that comes out of the fuel filter and goes into the fuel rail. When I installed the pump, the motor instantly ran WAY better. It did not run lean anymore and made alot more power. So right away, with no other changes it was alot better with the high-flow pump.
Then I installed the intercooler. Since the intercooler makes the air going into the engine colder, it has more oxygen per volume than without the intercooler. When more oxygen goes into the motor, more fuel is needed. The car ran good at 8psi but now it was running rich! So that pump was just slamming the fuel in there. I turned the boost up to 10psi and it just SCREAMED. I loved it. I drove it like that for a couple months.
Then I read that when the Bosch inline pump is used, you are supposed to remove the factory pump because it actually restricts fuel to the Bosch pump.
I was doing some work on the car and chose to remove the Bosch pump because I plan to move it to the fuel tank. So right now I am running the stock pump again. It is running WAY too lean with the stock pump even at 7psi. I don't even like driving it like that. So that is the limitation of the factory pump, can't even support an intercooled 7psi using the stock injectors and a rising-rate fuel pressure regulator.
So that is next, I am going to remove the factory pump and remount the Bosch pump just outside the fuel tank. I am pretty sure I will be able to run 12psi like that. I will update this page when I get the pump mounted where it needs to be. I am not using the holley pump because I already have the Boscg pump and can't spare the cash to get the Holley pump.