Fass Fuel System

Also this post is for Fass , didn't mean to highjack but seemed to fit topics discussed in threads...I .like the fass and the air dog....but can't get pumps to last on either and my trucks are work trucks not dyno queens...you can run it when pump quits but it's a restriction as well....

 

did you talk to air dog (cant remember the boys name) they had an update on the pumps. mine has ran for two years with no issues after the update.

 

From a Detroit 60 standpoint, I had to dig a little deeper in the OEM lubrications and filters manual to glean a little stuff about their micron size recommendations. Standard on the Davco is 7 micron. But, it all depends on the filtration percentage. One can run 15 micron with the OEM blessing if the filtration is 99% effective. At 7 micron, it only has to be 97.5% effective. So, while a lower micron filter might appear to be filtering better, it is allowing more to get by due to lower percentage of filtration efficiency. The resulting filtration is equivalent. It is easy to find quality filters, like Donaldson, that offer excellent filtration, so one can use a higher micron rating than stock. Eliminates many of the fuel pressure, cold flow, etc issues that many might experience staying with a extremely low micron filter. There is a point of diminishing return on micron size. Last time I lost an injector was in a Cummins N-14 in 1998. It is doubtful it was related to filter micron size. So micron size is not as critical as some assume.

 

Well, I'll just stick with the davco for now.

 

Me too. I have had great results with the Davco units over the years. And I like seeing my filter fuel level.

 

The FASS isn't a replacement for your Davco filter. You insert it in the fuel line going into your Davco as a pre-filter. Getting the dissolved air out of your fuel will improve the performance of your engine quite a bit. I'd say on my truck, I'm seeing just a hair under 0.5 mpg improvement overall. YMMV.

 

I'm not arguing with your results. I just don't see, precisely, how they claim to remove said air from the fuel.

 

Me too. I like the idea of seeing my fuel (what's in it and what's it doing).

Got mine installed except for cutting/hooking up the lines and wiring. I got the 12v fuel heater, which I'll operate via toggle switch and relay, when needed.
I also got the 3 micron filter. Not looking for performance gains. But if I can extend the service life of the factory DD15 filters, I should save some money.

 

There are anecdotal cases of an improvement using a FASS, but it is not consistent enough across the spectrum to convince me that it is worth it. And a fuel economy improvement variance depends on what the truck was getting to begin with. For instance, a low mpg truck might see a major improvement, while an already stellar mpg truck might see little or none. And when we get into tenths of a mile per gallon, there are many variables that can occur at the level to categorically prove that the modification was the primary factor. It has been studied, and shown, that in many cases, that tenth or two improvement was a direct result of the driver. How? Because they needed to prove that the mod they just dumped a thousand or more on did some good, the mpg improvement was actually due to the driver, even without realizing it, by improving their operation of the truck. So I always am wary of anecdotal results.

 

I keep very close track of my fuel economy. My truck has always turned in at 7.8 mpg when driven moderately at about 70-to-80,000 lb GVW. While I did manage to boost my 30-day average to just over 8 mpg for a couple of weeks last summer, the 60 and 90-day averages have remained solidly in the 7's for the life of the truck. Airtabs may have jumped me a tenth, but after installing a FASS at the end of May the 30, 60 and 90-day averages all climbed above 8 mpg, with the 30-day average at 8.4 mpg. Only recently with the advent of cold weather and winter blend fuel have I seen a decline in this. Additionally, before the precipitous drop in fuel prices, I saw a 3% drop in the fraction of my gross revenue devoted to fuel cost.

I keep very close track of all of this, so in my case its not anecdotal "gee by golly whiz" I got maybe a wild arse guess at this. This is empirical data I'm working from.

The real evidence for me is the rise of the 90-day average over 8 mpg. Additionally when I look at the lifetime fuel economy of the truck, the variability from tank-to-tank has smoothed markedly since I installed the FASS. You can scoff at this, but I've seen enough to be convinced of chalking up some real gains.