We sent a stock EVO fuel pump to RC Engineering in Torrance Ca to be tested. We had the pump tested at 12.5 volts and 14 volts. Also at 43 psi, 58 psi and 73 psi against the popular upgrade fuel pumps.

43 psi roughly represents no boost situations. 58 psi would be the fuel pump flow you get at ~15 pounds of boost, 73 psi is what flow you would get if you raised the base fuel pressure and/or cranked the boost well over 20 pounds.

Results here:
http://www.roadraceengineering.com/f...pflowrates.htm

We would call this stock EVO 8 pump a "160 lph" pump to compare it to other pumps.

DSM guys have been rewiring (direct 8 ga. or thicker wire to the pump triggered by a relay) the stock and upgrade pumps for years to get more flow from a fuel pump. You can see the big difference in flow that a 1.5 volt increase at the fuel pump makes.

The stock EVO fuel system does this in reverse. By cutting down on the voltage at low fuel demand times, it makes the otherwise big pump act like a small pump when it needs to.

http://www.roadraceengineering.com/e...elpumpinfo.htm


Mike W

 

Thank you!

 

So have you concluded anything as to at what power level we need to upgrade the pump?

 

Great information! So, since experience from various tuners has shown that the "standard" Walbro 255 pump can be used with the stock EVO FPR without over running the regulator, and at low voltage idle condition the standard Walbro 255 and Walbro 255 high pressure flow about the same amount of fuel, I conclude that you can run a Walbro 255 High Pressure pump on the stock Evolution fuel pressure regulator.

Does that sound correct to you Mike? If so, wouldn't the EVO regulator be an absolutely AWESOME upgrade for the 1G and 2G DSM's instead of spending the money for an adjustable fuel pressure regulator? Or would the fact that the pump would run at a constant voltage in the DSM's make this not work so well?

Keith

 

Kieth:
It is more because of the dual voltage pump set up on the EVO. By cutting down on the voltage at low air flow times, the pump flows less and does not outflow the regulator.

Mr Bonus:
On DSMs, people have been able to make over 400 hp on the Denso 150 lph pumps. But your simple question does not take into account what octane fuel or injector size. Higher octane fuel will allow you to make more power, bigger injectors will allow more fuel at the same pressure, and a bigger pump will flow more fuel by providing higher pressure through the same size injectors. Lots of different ways to get to the same result.

Mike W

 

Does anyone have the flow rates for the Lancer Evolution IX OEM fuel pump?







Oh yeah, sorry for bringing an old thread back, but I think this information is important to know.