Anyone with a fuel injected Harley should be paying close attention: Quite simply, it is not only far better when EFI systems are controlled by actual feedback directly from the engine (via sensors) it is also easier.
Older, open loop EFI systems, while more efficient than carburetors, also involve a lot more effort to be any more effective. Or it did. With the advent of so-called closed loop EFI on 2006 Dynas, H-D has made a giant stride in precision engine management. Trouble is, all the Factory system manages, in fact the reason for the whole EFI thing, is emissions compliance. The deal boils down to something like this: Narrow band oxygen sensors and an ECM/ECU that lock into lean 14.7 air fuel ratios on cruise. In effect, all the tools but no intention to offer true performance.
Zipper's Performance ThunderMax system, on the other hand, builds on this firm foundation by providing the exact set-up required to turn closed loop EFI into the high-precision, high-performance system it should be! Swapping the stock ECM for the ThunderMax unit and switching to Zipper's wide-band O2 sensors is pretty much a plug and play operation on '07 and newer Harleys (as well as '06 Dynas) but the real beauty of it is that folks with older, open loop factory fuel injection can update and upgrade as well by adding oxygen sensors bungs to the exhaust. (See the sidebar for more information on doing that correctly, courtesy of Bob at R and R American Cycle).
Once you install the ThunderMax with Autotune EFI along with the O2 sensors, you not only get fuel injection that can be tuned close to a stoichiometrically erfect 13-13.5 to 1 air/fuel ratio for bestpower from any combination of hop-up arts, but does it all automatically! To betechnically accurate it's more of an auto adjusting capability than actual auto tuning, since certain other parameters must be base-lined and a decent preliminary map must be installed, but we'll get to that...right now
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Here's what you get in the Thundermax with AutoTune kit (# 309-360) and it's ready to inst
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Once the kit is unpacked, to install it on a dresser as we are here, the next move is to r
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Plug the ThunderMax module into the factory harness jack, but do not mount the module yet.
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On machines that already have O2 sensors, it's pretty much a matter of routing the sensors
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Once that's all happy and cozy, you plug the AutoTune portion of the ThunderMax into the f
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Move on to installing the wideband oxygen sensors by adding a little anit-seize to the (cl
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Final torque (and believe me, you don't want to just reef on these things) is best accompl
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You'll need to run the wire harness plugs for each sensor to junction with the ECM harness
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Once you've got that handled, the next step is plug the respective (and clearly marked) O2
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After the remaining wires are tidied up, bundled, and ziptied, you bolt up the module. It
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Computer time! Take the Zipper's software CD and slap it into the PC of your choice to ins
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It takes awhile for the software to do its thing, but after that few minutes, and dealing
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Fire it up, then wait until the screen shows an engine temperature of more than 245 degree
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The biggest pointer we can offer is to select a base map from the files that are as close
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Once the Smartlink software boots, and the ECM is communicating with the PC, the instructi
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All that's left is to unplug, button up, and buff down as Steve and Bob are doing, then ge