| The Fitch F4424B, series F400, kit is rated for up to 400 hp and is a size bigger than the F3424, series F300, kit we actually needed. It's the kit designed for the 6.8L V10s but it gives us a little extra capacity for our power upgrades. |
Brain Twisting Science
Advanced Power Systems advertises the Fitch as a fuel treatment device that reformulates fuel. The way Chris Wright, COO of APS, explains it, the Fitch doesn't make good fuel better but "reconstitutes" degraded fuel. "Degraded" doesn't necessarily mean that nasty, evil smelling stuff you find in the tanks of neglected outboard boats. Immediately after gasoline is made, it begins to degrade. Essentially, it tries to revert back into its previous form. The longer between the time the fuel was refined and you use it, the more degradation has occurred and the more power and mileage is lost.
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| On the F-150's 5.4L, the fuel line feeds into the fuel rail at the back of the engine. A clip holds the connector and there's a spring loaded retainer as well. Put a rag there to catch the small amount of fuel that will escape and disconnect the line. Fitch matches these connectors perfectly so you can easily plug the unit in or out as desired. |
The Fitch uses a 19-metal heterogeneous metal alloy insert as a catalyst and APS tells us converts elements in the degraded fuel to alkanes, which are paraffins that contain hydrocarbons. Alkanes combust better than degraded olefins and aromatic compounds, so you gain back some of what is lost. The metallic alloy also reduces microbial action, which are little critters that form and grow in the water that may be contained in gasoline and may plug fuel filters.
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| Install the fittings onto the canister. The lock nut allows you to position the fittings in any position necessary for mounting and then lock it down. |
Affixing the Fitch
At first blush, the Fitch comes across as nicely made. The metal canister is well built and the fuel lines and fittings are top-quality. The units are designed in a variety of sizes to accommodate varying fuel flows and power ratings. The part number groups, e.g. F300, F400, etc., indicate the approximate "up-to" horsepower ratings.
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| Find a good place to mount the unit. In our case it fit perfectly on one of the master cylinder mounting bolts. |
In our case, it was simply a matter of finding a place to mount the Fitch with the straps supplied, uncoupling the fuel line where it meets the engine and plugging the Fitch into the system. Fitch wants you to reset the adaptive memory (if so equipped) of the fuel injection ECM by disconnecting both the battery terminals and touching them to each other. The ECM then quickly "relearns" with the Fitch added to the system. Total installation time was about a half hour on the F-150, including instruction-reading and figuring-out time.
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| Connect the Fitch's fuel lines into the circuit, both here at the canister and at the original Ford connectors. Pay attention to the direction of flow, as indicated by the arrow. |
Story deadlines wait for no man, so our initial testing was limited but we have some initial results. We ran one 350 mile tank of fuel through and, on the course used for previous tests, our accurized Edge Evolution indicated "snapshot" gains of no more than about 0.5 mpg at our lowest cruising speed but a slight loss at higher speeds. All these results are within a margin for error.
Then we got an idea for a better test. The author has a standby home generator and keeps a small amount of fuel stored. Normal rotation for this fuel is six months but the obscene price of gas forestalled the usual rotation in the hopes of a better deal. The rapid drop of gas prices in late October of 2008, gave us an opportunity to rotate that fuel, which was then eight-plus months old.
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| Disconnect the battery cables and momentarily touch them together. This erases the adaptive memory and the ECM can more quickly adjust to having the Fitch in the system. |
We ran our 55 mile loop and then reconnected the Fitch per the instructions and ran it again. This time we showed gains above a margin for error. The actual stats are in the sidebar but at our most economical freeway speed, 55 mph, we gained an average of 1.4 mpg with the stale gas. We gained less at higher speeds. The Fitch with the sour gas nearly equaled the fresh gas baseline, which was surprising. The drops with the sour gas versus the baseline illustrate how much mpg can be lost due to degraded fuel.
The Final Say
To be honest, we do not understand how the Fitch does what it does but it appeared to do something in our testing. It also appeared to live up to Fitch's claim of being able to revitalize stale fuel. Not many of us will have to use eight month old fuel, so your results will likely vary from ours. We will leave the unit attached and report any interesting long term results.
| MPH | 1.Baseline | 2.W/Fitch | 3.Sour Gas | 4.Fitch+Sour Gas | Gain/Loss 3 vs. 4 |
| 55mph | 17.9mpg | 18.4 | 16.4 | 17.8 | +1.4mpg |
| 60mph | 17.6mpg | 17.7 | 16.3 | 17.3 | +1.0 |
| 65mph | 17.5mpg | 17.4 | 16.3 | 17.3 | +1.0 |
| 70mph | 17.1mpg | 16.9 | 15.9 | 17.0 | +1.1 |
Source
Advanced Power Systems
www.fitchfuelcatalyst.com







