By looking at my mods will I benifit from upgrading to a Walbro fuel pump without upgrading my injectors. The fuel pump isn't that expensive and if I will benifit by delivering more fuel then I'll do it. Want to do injectors but they are so expensive. Thanks for any help

 

Yes, I think you will be more on the safe side, but then you would need to retune, since most likely you will be running at a higher fuel pressure than stock or the fuel system that comes with the Vortech SC…

If you ask me I would save my money and get a fuel system with a return line like the CJ Motorsport one and save some more for a set of 440cc injectors. That should set you up for any future mods

Az

 

I dont think the walbro will do you any good . Your aux, fuel pump and FMU is there to raise your fuel preasure and deliver more fuel . Until you get the return system and the pump , I wouldnt get the pump by it self

 

A higher flowing fuel pump won't necessarily increase the fuel pressure unless it completely overwhelms the fuel pressure regulator, which is unlikely. It will however, allow you to maintain the required fuel pressure (52psi in the Z) when your fuel supply is being called upon for extra duty, either with larger injectors, extra injectors, or a wet nitrous system.

 

I'm not aware of the workings of the Vortech SC fuel system, hence the word "Likely" in my previous post But now after reading your post, I agree with you.

Az

 

The walbro pump will make sure you will have enough fuel when your car needs it. It will operate the same as a normal stock pump under normal driving condition. Prob a good cheap insurance to have when you are running a FI application. In addition to that, I would recommend you to get a PLX wideband to moitor your AFR cause diff attitude will cause lean or rich mixture. Last thing you want is to run lean when boosting your car....

Thanks,
Tom
Gruppes
510-783-5300

 

Blatant thread hijack here.....

On the '04.5 and newer, don't the cars already come equipped with wideband O2 sensors? Shouldn't you just be able to tap into the signal wire with any basic A/F gauge to get wideband readings?

 

not unless the AFR gauge is scaled to read a 0-5 volt signal (I cannot think of any that are). not to mention tapping that signal is not the ideal way to do things...much better off running a dedicated sensor

 

If you have a Vortech SC . with the aux. fuel pump , your not going to need the walbro in tank pump . The aux. pump supplies all the fuel and preasure you will need . If you upgrade to a return system and ditch the FMU and aux. pump , then you will need it . NOT UNTIL THEN

 

If you just upgrade to a Walbro 255, it WILL NOT operate just like the stock pump. The Walbro at idle will over power the stock FPR and you will have about 70psi of fuel pressure at idle, vs. 52psi stock. The RPM's rise, and the demand on the pump increases, your fuel pressure will drop, and level off around 52psi as redline approaches.

You could just replace the fuel pump, as a temporary solution, but the real solution is a return fuel system, rising rate FPR, and stock FPR plug/syphoning kit.

A lot of members are using the Altered Atmosphere return fuel system:
Click here: http://www.forgedinternals.com/store...cat=251&page=1

 

Agreed....with increased idle fuel pressure at idle you will be dumping extra fuel into the cylinders which will kill your rings in a heartbeat. Not a good idea.
You would certainly have to tune for the increased pressure low in the rpm scale.

 

the increased pressure would NOT kill the rings! You would need to tune for it though, and all in all, it's a horrible way to do things.

You need to introduce a return style system and conventional FPR to the system, and combined with properly sized injectors and a Walbro, you'll be in good shape

 

So you are saying excess fuel doesn't kill rings???? I beg to differ. I have seen more than 1 set who were sharpened to a knife edge from overfueling that washed the bores of oil.

 

excess fuel certainly can - but not as a result of running this pump on this car without other changes. It takes ALOT of fuel to bore wash a cylinder, much more than this pump can cause

 

Is this somthing N/A drivers should keep in mind as well. Or is this product solely beneficial to F/I users? Also, all you would need to buy is this kit and a Walbro fuel pump and you are set?

 

at a certain hp point yes it benefits an NA car - I am keeping it in the back of my mind for the mods about to commence to my own car, but we'll see if it actually needs to be done. I do think the Walbro is "too much" pump for most stock displacement NA setups, though they offer a wealth of other pumps that would fit the bill well, should an upgraded pump be needed