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I know 5-6 years ago people were having problems using any cam with a LSA less than 114 degs without having to retard the cam 4 degs when using the Explorer computer, anything changed? Can this now be done with a programer? Bet Chris is the first to answer! And I bet it's the right answer.
Dave

If you are using the stock tune, that's probably about right. Although I don't know anybody that's actually tried slightly more aggressive cams like the Crane 2020 or Comp XE258HR. Both of those have LSAs around 112, but still very mild off-the-seat durations to keep vacuum up and torque strong at the low end.

But yes, if you are tweaking the tune, your options on cams go up dramatically. The newer EECs are far more "tweaked" to the engine to detect problems with the engine much earlier and to detect far more specific problems than the older EEC-IVs could. As such, there's more than needs to be touched in the tune to make the tune happy. But with the right editing software and support, you can overcome those issues without too much issue IF you know all the things that need to be touched...therein lies the hard part.

For those of us with slow memories what's the issue that arises from having less than 114 LSA with the Explorer computer? poor idle, hesitation etc.?

To be honest, I don't know. Although I would expect more EEC issues to come from wider duration cams than specifically LSA...more on that later. If I had to guess I'd say if the cam is still mild, just not as mild as the computer would like, then probably the most notable problem would be hanging idle. The EEC will likely expect the engine to be at a different RPM for the given Throttle Position even though it has a MAF sensor to know that the air coming in would justify the RPM. When it isn't at the expected RPM, that confuses the computer, leads it to believe there's some problem (e.g. vacuum leak, mal-adjusted throttle plate, stuck Idle Air Controller, etc) and it throws a code and a CEL. Although I would expect the EEC to have enough adjustment room to adjust for a mild cam and possibly even learn the adjustment. What I don't know is if it will allow itself to "learn" while a code is triggered. I just don't have any experience tuning on the Explorer EEC to know what its behavior and expectations are.

With a mild cam, I'd expect that to be the biggest annoyance if that. A mild cam with LSA of 112 is probably not enough different than the Explorer cam to make much difference and I wouldn't be surprised if you could get away with a mild cam on a stock Explorer tune. Part throttle conditions should be fairly unhindered. Although there's plenty of room to improve on the stock Explorer tune even with a 100% stock engine. The spark map for the Explorers is extremely conservative. That'll be the 1st thing that gets updated assuming you plan to run a higher octane fuel. Even with 87 octane, I believe I have most of my spark set higher than the stock Explorer computer from about 2000 RPMs up. Although at the lower RPMs, my spark table is probably about the same, if not a little less to keep the ping down.

However a wider duration cam with LSA of 112 is a different story. Wider duration cams are where you start running into trouble. I, personally, classify any cam with an intake duration higher than 216°@.050" a "big" cam that has the potential to cause driveability problems (exhaust duration can go higher without causing issues). With a big cam, the engine just can't run as low of an RPM as it can with milder cams. So no matter how much you try, the engine is just going to be unstable at lower RPMs. Computers don't generally like to see the engine "camming" on the edge of conking out. To alleviate that, the tune needs to be updated to maintain a higher idle RPM that can be held stable. Although with the right tuning, you can tune-out the code thresholds so the EEC will be tolerant of a camming idle without throwing codes...but to get that right often requires a fair amount of trial-n-error. An experienced tuner will know better how to get that to happen. But a DIY tuner will tinker until it idles the way they want, but won't be considering how the engine will behave cold. Often they'll crank up the next day after the engine's been sitting and find it won't stay running when the engine's cold or the idle will surge up-n-down until the engine is warmer. Same story as you start getting into cams with LSAs of 110, which have its own mix of mild and "big" cams with even wider durations. Then you have full-blown surging/unstable idle, lean tip-ins, and lean bucking at cruise as you transition through the different RPM/Load conditions which requires more than just idle tuning. By then, you are needing larger injectors and MAF which will need to be part of a new tune anyway. Once you get above 93 Mustangs, the computers quit working with "calibrated" MAFs. You pretty much HAVE to get the tune modified to work with the MAF and Injectors you have.