I'm pondering the idea of purchasing the regulated fuel return from riffraff. I've heard good things about the mod. Quieter operation, extended longevity. One question have is this: Would the addition of the return lines eliminate the need for the AE injector in the #8 position? Since the AE injector is the one that is put there for a delay due to low fuel volume in that area, I am thinking the increased fuel volume brought about by the regulated return would solve that problem. If so, replacing the #8 with an AD injector in order to get #8 back into time with the rest of the engine could result in a smoother running diesel along with everything else that goes along with having the engine work smoother.

 

You'll need to address both fuel and oil since the firing order affects both of them. I'm not so sure pulling out a perfectly good AE and replacing it with an AD is worth the money. The only difference you're likely to notice would be when it's on a scanner.

If you do the mods and are replacing the injectors for some other reason, then you can skip the AE going back in.

 

The FRx is a good addition that helps smooth out the truck nicely. Like Chris said, not worth the cost swapping over the AE injector. You should also try getting an original black CPS. That made a big difference in the testing I have done.

 

Already have the black CPS, picked one up from Navistar, just replaced the injectors with a rebuilt set along with the glow plugs, wiring harness and valve cover gaskets. Had a pretty bad knock in the #8 injector before and now that is fixed. When it was started from dead cold, one of the injectors, I'm assuming #8, was completely dead until the engine warmed up a bit. All that is solved now, it starts well when cold, but still surges for about 30 seconds like I've heard a lot of diesels do. Not just powerstrokes. I did put a fuel pressure regulator spring to increase the pressure some, but I'm thinking that eliminating the deadhead would do the most good.

 

Also switching to synthetic oil sounds like it would help too!

Here is a post I made when I installed my FRx. I had been tracking PERDELS to see if it made a difference.

Riffraff FRx Lowers PERDELS


Also a video I made before and after the install.

Riffraff FRx.mp4 - YouTube

 

The FRX will make a difference go for it. I had a bad knock and installed it and it cut it in half. I haven't changed my injectors yet but that is next.

Chet

 

if you have A/E # 8 injector can you still install the frx return line just for extra insurance to help the other injectors last longer or would it be a waste of $$,thanks

 

The FRx is a good MOD no matter what injector you have in #8. My E99 didn't have an AE in #8 and cackled like crazy. I put in a fuel crossover and couldn't believe how much quieter and smoother it idled. The FRx is worth every penney.