I haven't heard much about these except on other makes and models and Evo X, and until looking at Radium's product lineup building a new fuel system. Search here yielded a surprising zero except one FS thread years ago. Some OEM cars come with them, some don't. Obviously people have set many records and accomplished tremendous results without them. But do they offer potential benefits that people are overlooking, or solutions to problems some people may have but not know how to address properly? It doesn't seem like it could hurt, but I am wondering what people think about them at various power levels and higher fuel requirements.

 

What I believe is that it will help stabilize the demand between the injectors as they overlap. I believe that it stabilizes the bouncing back pressures to lessen the vibrating resistance to the pump and help pump to live longer. Just my 2 cents.

 

Exactly my understanding as well. I am trying to figure out whether it is something I could benefit from while I rebuild the entire car right now.

Speaking of fuel pump life: Years ago after getting tuned on E85 with my 9.8 stock turbo, I was burning through rewired fuel pumps to an absolutely ridiculous extent, experiencing very annoying "ghost rev" up to 3800rpm at stops and throttle hang that I could not seem to fix no matter what I tried, including asking everyone here and taking it back to the shop that did the work and tuned it. I burned out my Walbro 255, then an AEM, another AEM, a DW300 or 2, went back to a Wally 255 all in about a year or 2. No idea if a FPD could help with those issues but I definitely don't want to deal with that stuff again on my new build.

 

There was a post on here a while back (maybe Pal215 project car build thread) where the owner was continuously chasing down a spot in their map that was always lean. Eventually installed a Radium Fuel Pulsation Dampner and it instantaneously resolved the problem. Maybe do a search for Pulsation or read through Pal215's build thread in the project car section for more info.

 

The spikes and dips in oressure can create a harmonic which creates lean spots in the tune that can't be fixed by adding fuel in the fuel map (increasing IPW in that area). By smoothing the spikes and dip and not allowing these harmonica to form, an FPD prevents these lean areas.

Nothing to do with pump life.

 

Thanks I'll check it. I have dealt with that in the past as well. My tuner suggested I rewire my pump, and for some reason doing this lead to a whole ****storm of many many pump failures until I reverted it.

Thanks for explaining. It sounds like it could be worth it.

 

It's really only worth it if you're having the specific issue it solves.

 

How the heck is this "re-wire" job being done? Full power all the time?
You have a serious issue to be burning through pumps like that. I have never burned out a single pump.

 

Yes, the way everyone does them. I don't want to get too OT, but it was back in 2013, using and STM rewire kit, probably a half dozen people including performance shop professionals and various highly esteemed EvoM verified it was done correctly. The thread is here https://www.evolutionm.net/forums/ev...fuel-pump.html

The weird thing was my pumps seemed to be eating themselves alive and my fuel sock filters were full of pump brush debris material every time one failed.

The only thing that seemed to make it stop was going back to stock wiring setup, and making sure my tank was always very full, and living with the aforementioned "lean spot".

Still a mystery until today (car was wrecked in 2015, rebuilding in new chassis now)... unless the breather port on the pump mentioned on the last page of that thread was the culprit on both the AEM, DW300s, AND Walbros.

/campfire war story

Bottom line is, there was a lean spot in my tune my tuner could not fix through tuning. This led them to tell me to rewire my pump.

Rewiring the pump should not have been a problem, but my point is maybe the lean spot could have been solved with a FPD.

Given the headaches I dealt with, I am just replacing most of the fuel system vs. moving it to the new chassis, possibly using Radium Products including the FPD

 

you shouldn't run the pump full power all the time on the street. It will lead to premature pump failure. The stock wiring has the pump at a lower power state when demand is low. There are threads on how to wire up the pump with the stock low power mode but with extra power for high demand.

 

Sorry, I may have been mistaken, as this was seven years ago and my Evo has been sitting for 4 years so my memory of the wiring is not the best. I followed this:
https://stmtuned.com/products/stm-fuel-pump-rewire-kit
and this, pics have disappeared
https://www.evolutionm.net/forums/ev...mp-rewire.html