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3L Straight Swap into a 98 (return) style.

Lets agree upon a couple things first:

-Fuel pressure regulator is there to keep the fuel at a constant pressure.

-Specifically, the pressure should be kept constant at the fuel rail where the injectors are located.

-An FPR has an inlet and an outlet port.

-The fuel before the inlet port of the FPR will be pressure regulated.

Agree?

-fuel pump> Injectors > FPR > return line> Tank
if you statement is true about pressure drop between 10" of 3/8 ID fuel rail

Ex. of OEM split port return rail values guessimated with 1 psi drop
stock FP 190lph @ 55 psi { Inj. #6 @ 54 psi > Inj. #5 @ 54.2 psi > Inj. #4 @ 54.4 psi > Inj #1 @ 54.6 psi > Inj #2 @ 54.75 psi > Inj #3 @ 55 psi } FPR @ 55 psi > return line @ 10 psi

and mine you would have the same setup too

Ex. of oval port return style

stock FP 190 lph 55 psi { Inj #6 @ 55 psi > Inj #3 @ 55 psi > Inj #5 @ 54.8 psi >
Inj #2 @ 54.8 psi > Inj #4 @ 54.6 psi > Inj #1 @ 54.6 } FPR @ 55 psi > return line @ 10 psi

the two example are the same except for the fact that the returnless has less distance between the injectors because if you stretched ou the two rails which one would be longer OEM split port rights

###### OEM split port ######

Cons
* length between ports means more variance in pressure drop due to restriction
*smaller ID making the velocity whixh once again is negative in aspect on flow with fluid
*FPR is closer to the injector #6 where the fuel compresses up against the FDR restrictor making more pressure at the end (think of it as a water hose where is the highest pressure at when spraying out of a nozzle(restrictor FDR) at the tip right?

Pros
any? trash can be filtered back to the tank (if fuel filter failed)

OEM dodge also mine

Cons
*trash may build up on the end of fuel rail (if fuel filter failed)

Pros
* shorter fuel rail less chance of pressure drop between injectors
*larger fuel rail ID good volume right at the source (injectors)
* FDR is not close to the any injectors which helps prevents large fluctuations in pressure
* there is not a constant flow across the injectors to create turbulance (restriction)

Now ask your self this why does Mazda 6 have there pressure sensor by the fuel tank if the sensor or regulator if the FRR is so important after the injectors? Even the Escape fuel rail does not have it pressure sensor after the fuel rail because measuring the pressure after the injectors is not important and neither is it before. The only thing you need to worry about is the size, shape and length of the fuel rail. Now if you thought my regulator was setup wrong I would understand how you would think it will not work. Just imagine that you have a one fuel line going to the fuel rail (dodge) and the regulator input port is on a Tee where once the pressure reaches 55 psi it bleeds it out of the small low pressure side of the FDR where dodge's is mounted on the tank to avoid extra fuel line for return. So only difference is I return in back down to the tank on the factory line. It is not hard to do just take to much precision for people to drill and mill and tap and time when I sell them for $99 hope you see what I am saying but I remember you jumping on everyone who want to do SVT UIM @ newcougar on my post saying it is not big enough well this Wednesday we will see for sure to back up all the flow charts we have on datalogs from SVT UIM and Oval port where the SVT UIM
draws in more air based on MAF counts. Sorry if I came off wrong but you seem to follow with opposing info with no data yet making me feel like it is personal more than a debate......peace
 
Lets agree upon a couple things first:

-Fuel pressure regulator is there to keep the fuel at a constant pressure.

-Specifically, the pressure should be kept constant at the fuel rail where the injectors are located.

-An FPR has an inlet and an outlet port.

-The fuel before the inlet port of the FPR will be pressure regulated.

Agree?

oh I forgot to respond to the why FPR is effective just about anywhere is because fuel is not compressive like air so pressures stay constant are near level across the lines.
 
Compressable not compressable is not the point fuel is liquid and the FPR is just basically a liquid pressure regulator which can withstand corrosive fuel...

The FPR is made for one way flow of fluid, I am not familiar with the dodge system... Either way I don't think they have the FPR sitting somewhere where there is 2 way flow of the fluid and its probably not restricting the fuel flowing into the fuel rail

In the way you have it setup 1. you are restricting the flow of fluid into the fuel rail and 2. you have a fluid flowing in both ways in the FPR...
 
Compressable not compressable is not the point fuel is liquid and the FPR is just basically a liquid pressure regulator which can withstand corrosive fuel...

The FPR is made for one way flow of fluid, I am not familiar with the dodge system... Either way I don't think they have the FPR sitting somewhere where there is 2 way flow of the fluid and its probably not restricting the fuel flowing into the fuel rail

In the way you have it setup 1. you are restricting the flow of fluid into the fuel rail and 2. you have a fluid flowing in both ways in the FPR...

fluid flows both ways it not correct term because the fuel is not backing up it is spliting. And the fuel injectors and FPR are both pressure relief areas meaning they open up to create gates or ports. The system I uses Tee's off just like injectors do in the fuel rail think of it like this FPR is just a injector that is regulated to release pressure to maintain constant pressure. The dodge has a regulator built on top the tank that sends the discharge back to the tank (Tee'd) No matter where you test the fuel rail it will have the same pressure on eithers side plus the PCM adapts to different fuel pressure by adjusting the MAF when at cruise or idle. I will let Tom who is a engineer in fluid and metallurgy tell you the facts because I am sure he will quote things up for you I will draw out a sketch tonite to have a little debate and anyone with knowledge feel free to chime in I am not expert in anything but I am willing to admit things if I am wrong. I will maybe do a better test for you I have another fuel rail I will weld in a fuel guage at the end to show you there is not one difference between the two. If you want to help people here design a intake that keeps number 1 cylinder from being the hottest and leanest combustion chamber due to the heat soak and longer tract too. Joey
 
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