Adjustable fuel regulator needed or not?
 

Hi, I have just fitted a Hybrid FMIC and am looking to get a remap soon and thought I might as well get an up rated fuel pump and a 550cc injectors put in as well to compliment the FMIC, while doing some investigation into fuel pumps I read that on impreza’s it’s a good idea to get a Adjustable fuel regulator, but when I asked the garage that will be carrying out my remap and doing the mods they said that the AFR was not needed and not for me to waste my money on one?

What are your thoughts on this?

Many thanks

An uprated ( say Walbro 255 l/hr ) fuel pump can pump at higher pressures and flow more fuel, and the OEM fuel regulator may not be able to hold back the fuel pressure ... one benefit of uprated fuel pump is to be able to increase the fuel presure at the injectors and make them squirt more fuel in per pulse, so making them look like bigger injectors, which the mapper will take into acount. That can't be done with a std fuel reg. If you are fitting 550's then this may not be needed, but care with the pump overdoing the std. fuel reg.

Of course, if you are well within the fuelling requirements of your new set up then neither fuel pump or reg are needed ... but if doing a pump a reg is suggested!

It is not normally recommended to fit a high flow fuel pump with the oem FPR for the reasons shown below :-

Cheers

Many thanks guys.