S5 na fuel pump upgrade question.
 

I have a S5, the tank was nasty from sitting for a few years, while I'm getting the tank redone I was curious if running a bigger pump would cause issues with the na motor? I have future goals of 400hp and would rather only buy one pump if I can. Someone mentioned a bigger pump could cause issues because of the amount of fuel that would need to come back through the stock fuel line return. Thoughts are Walbro 255 or Aeromotive 340.

Welcome to the board. :)

I can understand wanting to buy one pump to cover your present needs and your future endeavors, but in order to do that you will need more than just a pump. I think the simple (and sensible) solution right now is for you to just get the correct pump until you have everything in place to start building for 400 HP. You are setting yourself up for many headaches if you put those pumps on an otherwise stock NA car.

You can see for yourself here: https://www.rx7club.com/2nd-generati...55-lph-633550/

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This is exactly the information I needed, thank you sir.