Shimming the fpr?

[BIG JOE]

Yeah Richard, the OBS have a mechanical fuel pump still while the SD is electric. The OBS will like to run a little higher or I should say will tolerate it higher. Much over 70 psi and the SD will eat fuel pumps for lunch. The OBS will run 75-85 psi easily.

Is the Method the same Mike ?

Joe

 

[95_stroker]

Is the Method the same Mike ?

Joe

94-97 FPR shim procedure.

99+ 7.3L SD FPR Shim procedure

and for those that asked or are interested...

10K resistor mod

 

[JRJ04]

10K mod is an injection pressure mod, its on the HPO side of the circuit, not the fuel side of it.

and what is achieved by this other than the fact that it raises your injection pressure...i guess what im getting at is whats the benefit of it?

is the 10k doable for my truck too? 2002...or this only an obs mod?

 

[95_stroker]

and what is achieved by this other than the fact that it raises your injection pressure...i guess what im getting at is whats the benefit of it?

is the 10k doable for my truck too? 2002...or this only an obs mod?

The 10K mod gives good low end throttle response and better fuel atomization because it raises the injection pressure. Some say it does this at a little bit of top end performance but I never noticed it in my 95. Yes this is a doable mod on your 02.

General note to all'a y'all, put a pyrometer in prior to messing with fuel and injection pressures.

 

[JRJ04]

one last question...do either of the 2 mods mentioned in this thread have the possibility of increasing fuel mileage?

 

[95_stroker]

one last question...do either of the 2 mods mentioned in this thread have the possibility of increasing fuel mileage?

Thats a tough one to answer as it really all depends on driving style IMHO. But I think all the different mods combined do make these engines more efficient in one facet or another. The open element air filter, full size down pipe, 10K mod and FPR shim all have cummulative effects that if driven properly will net you better fuel economy.

How was that for talking completely around the question?

 

[hawkdriver]

I've been meaning to get around to the FPR mod for my '01. I have a question or two though. I assume you can use a fuel pressure gauge that you can buy from Summit, etc. One that will be permanently installed under hood? Where, exactly do you install it? If there were pics of the gauge installed it would help a good bit to save messing something up.

 

[JRJ04]

Thats a tough one to answer as it really all depends on driving style IMHO. But I think all the different mods combined do make these engines more efficient in one facet or another. The open element air filter, full size down pipe, 10K mod and FPR shim all have cummulative effects that if driven properly will net you better fuel economy.

How was that for talking completely around the question?

haha well...I think thats a pretty straightforward answer given the question. its hard to prove which of them do what...but i have found truth in combining things to get the overall net effect. I'll have to add those mods to my never ending to do list

 

[95_stroker]

I'll be honest with you Jourdan, my 95 had Stg I injectors with a 4 POS chip along with the mods being discussed in this thread and a few other mods but I had no problems getting 17-18 mpg with it all day long.

 

[95_stroker]

I've been meaning to get around to the FPR mod for my '01. I have a question or two though. I assume you can use a fuel pressure gauge that you can buy from Summit, etc. One that will be permanently installed under hood? Where, exactly do you install it? If there were pics of the gauge installed it would help a good bit to save messing something up.

Make sure you get a liquid filled guage, just a standard guage will die a horrible death. The injection circuit has a radical pulse which will make reading a standard guage nearly impossible.