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Okay so I know the basics of how a fuel pump works. I also know that when boosting the BP, people will usually go with a higher rated fuel pump (Correct me if I'm wrong but the late 80's RX-7 fuel pump can be used as a higher LPH pump). Now my question is, if running a stock BP with anticipation to boost later on, would upgrading the pump do any harm? Is upgrading the fuel pump going to throw off the air/fuel mixture when running a stock setup?

I am just curious as to how that works. I am still running the factory fuel pump, and it's got 155,000 miles on it. I am thinking of replacing this pump soon, but would only want to replace it with one that I can use for my 10-12 PSI boost setup.

Do you know how a FPR works?

99% of the flow produced by the pump is sent back to the tank (at idle)

Your stock fuel pump will become an issue when it cannot maintain the pressure needed when the extra volume of fuel is being used by the bigger injectors/longer timing.

The stock pump maintains the PSI it needs at all RPMS, but as soon as you get bigger injectors and a more aggressive tune, it may not be able to maintain the PSI with the extra flow, so you need a high flow pump that can maintain the proper pressure.

I ran a Walbro 255 LPH on a stock setup for over a year with no problems before
I turbocharged.

You can purchase a nice FPR and get the fuel system out of the way now to make
doing things later easier / less expensive all at once. Do not cheap out on the FPR.

Check out my post, might help. viewtopic.php?f=1&t=76200 The HP is good for aspirated and turbo'd.

Mi|<E wrote: You can purchase a nice FPR and get the fuel system out of the way now to make
doing things later easier / less expensive all at once. Do not cheap out on the FPR.

QFT

Don't want to lean out, or blow a line.

okay awesome information!!! That's what I figured!!! Thanks!