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Fuel System Questions

2 November 2006
Berkshire NY, Port Charlotte Fl
I'm going to do the ProSpeed RDX Injector mod soon, and maybe a CT supercharger in the future, and now I have some questions.
What are the flow ratings for the fuel pump that came on the car? Where does one find such information?
When I look for fuel pump replacements, I come up with Denso and Bosch and others, but none of them list flow rates or other operating parameters. I'm left to assume that they are similar to OEM, but that could be a bad thing.
When you guys update your fuel pumps for FI, do you change to a larger capacity fuel filter, and if so what?
Thanks; Howard:confused:
This is a great thread talking about a lot of the various pump options available and links to various tests showing the flow rate vs pressure:

According to SOS, if the Walbro HP 255lph is ~65% greater than OEM, then OEM is ~255/1.65=155lph.

Larger capacity pumps may require a more robust wiring mod and a different FPR. Extreme high flow setups will require those in addition to modified fuel rails and fittings, and a larger capacity fuel filter.

IMO, with the RDX injectors and a later CTSC, just a new OEM pump or Walbro along with a fresh OEM filter is sufficient.

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I would not use a Walbro. I have had 2 of them fail and they will not warranty their pumps. For warranty you must pay them to test it and if it is not warranty you are out another 40 bucks. May as well buy another pump for 40 bucks more and get warranty. I ended up using an Aeromotive Stealth 340 lph and have had no issues at all. IMO this is the pump to use. They also supply fuel filters and FPR's. It is always nice to have matching parts.
Ar you using E85 Mr. Bozo? I've heard of problems with E85 and the Walbro....

I've also researched Walbro problems on the internet and have come up with a few. However, statistically speaking, I think they are still a good product. ALL of the aftermarket people use them, from American and import scenes....

For a drop-in pump that doesn't require wiring mods, it's the way to go for up to 500HP goals.

My 450WHP plan is to use an Aeromotive 340lph pump (custom wiring and relay) with a Fuel Lab FPR and Fuel Lab filter, and modify the fuel rails so they are fed equally (so the rear bank doesn't get potentially starved of fuel like it could be for high HP applications). Obviously, this isn't necessary for RDX injectors or the low-boost CTSC.