Installed frx and the hpo crossover at the same time. So far i think it has made a big difference in throttle response. I cant quite tell if it has "quieted" the engine down but i can tell a huge difference in how smooth it runs, especially when takeing off from a stop, the engine just keeps going without bogging down no throttle needed to keep engine running smooth. So far im happy with it. But its only been 2 days. I would love to see 2.7 mpg increase like some people have claimed! If i do ill be sure to let everyone know. But even without that, I would recommend this product to any one with a 7.3l.

I installed both the Riffraff FRx and HPx at the same time, Installation was relatively easy. A little bit of a PIA to access the front FRx fitting with being a tight fit in that area. Rear fitting was easy to get to, especially with air intake boot removed to access the HPx fittings. It does seem quieter inside the cab of the truck, but I can't say for sure. Might just be me expecting it to be more quiet with these items installed. Regardless, by design these items should help out my 2002 Powerstroke. Another quality product from Riffraff diesel.

What a great product. Does exactly what the say and more. 2.7 mpg gain! Wish I han't waited so long to buy this.

Did this upgrade with the cvd fittings and the oil cross over. Made my truck run 10x better. This is a must if you got yourself a 7.3.

Decided to add the FRx to see if it might quiet my 2000 F350 down a bit. It seems a little quieter, and I like the idea of having an escape rout for the air in the fuel to prolong injector life.
Passenger side fitting a real PITA. Good test of my patience and perseverance.

Only difficult part of install was the passenger fuel rail plug. A universal and 8 point did the trick though. Made the engine a little less noisy and idle smoother. Did the banjo bolts and CVD while I was in there and picked up 2 MPG when I keep my foot out of it.

Took better part of 2 hours to get that darn passenger fitting into the head. Finally discovered that the fitting threads in the head aren't aligned with the other bolts nearby. Also needed to move the A/C compressor over a bit to get some more access. Once I got the fitting alignment thing figured out it was pretty straight forward. By comparison, the driver side fitting was easy to install. This mod, combined with the HPx, did seem to smooth out my idle some. I still need to do the Hutch mod, so it isn't perfect yet.

I did e fuel conversion on my old 97 I used to own. It was a pain in the rear. I was worried when I bought this for my 02 Ex that it was going to be tough as that old truck was. This was so easy and helps the truck a lot. It is such an easy install and does the job well. Riffraff is top notch quality products and shipping. Only thing I don't like is I liked getting the Riffraff decal stickers and I haven't got those in the past few orders. The little badge stickers are okay but those other ones are great. I keep one on my 02 Ex. I like supporting companies that have great products like Riffraff.

Love this product! Before install had alot of cackle from my 250cc hybrids. After install noticed a smoother idle and top end!