So i want to get one dillema out of my Head...
1. What if i Dont take out the Comptech FPR when using EMS??
I mean Not to take it out but To use it as the OEM FPR, With just taking the Vacum-boost feed line to the FPR to make it as a Steady state FPR.When you take the Vacum line off the fpr and the FPR in theory should Function as a Steady state FPR since it will see only Ambient Pressure or 0 on a Boost gauge. Than the Comptech can be used as the OEM FPR right?Since Comptech uses Vacum line to see boost and rise the Fuel pressure rate..Right? I see it like this,if you take the belt off the SC and drive the car as NA the Comptech FPR acts like the Stock FPR right?
2.What pressure does the OEM FPR work whan in idle and what pressure does the OEM FPR makes when in WOT or in 0 boost?No vacum?
3.Also the only purpuse that the Fuel Pressure gauge on the fuel rail serves as you can monitor the Fuel pressure when the car is on the dyno right? And to adjust the Idle FPR... You Really dont know what Pressure you are when you go WOT on the street right?
4.In the end,what Fuel Pressure do you guys use when You change injectors and use a AEM type FPR? Whats the FPR when in idle and whats the FPR on WOT?

Cheers.

 

What you say is correct, but it won't work. Lets say again that your base fuel pressure is set to 45 psi. If you boost to 20 psi, you will have 20 psi on the output of the injectors and 45 psi on the inlet side of the injectors. Your injectors will only be operating at an effective fuel pressure of 25 psi (45-20). Not a good situation.

 

Well how does the AEM FPR work then?
Does it rise the PRESSURE Up 20 psi when i boost?

 

It's a 1:1 FPR, just like the stock FPR. At 10 psi of boost, the fuel pressure would rise by 10 psi.

 

The way you set an aftermarket FPR is to disconnect the vacuum line to it at idle and set it to aroun 47-54psi. When you reconnect the vacuum line it will decrease because at idle manifold pressure is less than ambient.

At WOT throttle fuel presure will be at 47-54psi plus manifold pressure above ambient. If NA that should be 0-ish (allowing for some restriction). If FI at 10 psi that should be 57-64psi.

 

Thanks for that...Now i understand why its called 1:1 and thanks for sharing how its done. So what ever Pressure i Tune it at idle ,no vacum, and with every psi of boost i get one psi of fuel PRESSURE more...
in the end how do i know at what pressurse the Base AEM map i have is tuned for?
also does the Vacum on the FPR works both ways? I mean the higher the Vacum is the lower the F-pressure is when crusing? from the Set of when its 0-?

Now thats good. good info

another thing came to my mind...So does OEM work the same way?Since Honda made the Car NA and they would rule out boost? Does the OEM put a psi up for psi?

 

The stock FPR is a 1:1 and works fine on boost. At least up to the 2005 model year. After that, I don't know.

 

Also, one good thing about having an adjustable FPR is if you have it tuned and for some reason you change something which makes your turbo system a little more efficient. This can cause the A/F to get a little leaner if you have an A/F gauge and can see it and all you have to do is turn the fuel pressure up some to bring it back to a safe point until you can get it re-tuned.

 

Well, I don't have an A/F gauge, but I could datalog to see how she is running.

 

Ok...I am going to stick with my AEM FPR. I like some of the features of the Aeromotive FPR, but it doesn't come in blue.