Even with our level of engine building and tuning experience, the ability to accurately tune Harley fuel injection by road testing is limited. Everyone seems to be looking for the cheap fix for EFI, but quite honestly it just doesn't exist. If it did, we'd be using it and selling it, instead of having to have made the massive financial investment in our Superflow dyno facility.
We only tune Harleys here and our extensive knowledge of tuning carburettors, and now fuel injection, puts us at the forefront of the market place. We are an authorised tuning centre for the excellent Technoresearch Direct Link Flash Tuner software, which gives us full control over the stock Engine Control Module. As well as component choice, machining, and workmanship, tuning is a key player in any engine's performance and reliability.
For earlier EFI exhausts that do not have oxygen sensor bosses, we have built our own system that allows us to still take these essential readings. After tuning, the holes are plugged with stainless screws, which are then covered by the heat shields. This '07 Screaming Eagle V-Rod now produces 121 bhp.
Since we are engine builders, then we also have to be tuners, and since it is our belief that it's incorrect to sell parts that we can't fit (which is why we have a machine shop), we also take the view that if we can't tune it, then we shouldn't be building it. That's why we have the Dyno...
As well as our own builds we also tune Harleys that have been modified elsewhere. We do prefer, however, to tune Harley fuel injection with the Direct Link Flash Tuner system, which requires the purchase of a hardware key to allow access to the ECM. The reason for this is that we can display and record data logs with this system and also (very importantly) use the autotune function to relatively quickly remap the Volumetric Efficiency tables for each cylinder.
This is the only way that the ECM knows how much air is entering each cylinder at different rpm and throttle openings, and without these being accurately modified the fueling is all over the place and tuning becomes pure guess work. The use of Direct Link Flash Tuner greatly reduces the Dyno time required, and therefore the overall cost. Please talk to us first before committing to another tuning method.