Get more power across the board with the all-new APS Ultra Performance at Idle (UPI) series of high output alternators.
The UPI series is APS’ next-generation line of alternators based on our original High Performance at Idle (HPI) alternator series. The new alternators share the same weight, size, and other mechanical specifications as the HPI versions but with higher output at both upper and lower ranges of the RPM output curve.
In addition, the increased power output at lower RPM means faster charging capability at lower speeds, including at idle. Because they’re based on the HPI platform, the new UPI alternators offer the same form and fit as HPI versions in under-the-hood configurations for all vehicles APS products currently fit.
While the new UPI high-output alternators offer more power at both ends of the RPM spectrum, they can start producing electrical power at lower RPM, which translates to quicker battery charging. Lower turn-on RPM means that the alternator can start generating voltage earlier in the engine's operation cycle. This early activation reduces the dependency on high RPM for effective charging, making it possible to maintain optimal battery levels even during low-speed operations.
This is especially useful for vehicles in an idling scenario (low RPM) or in city driving where vehicles often run at lower speeds. By starting power generation earlier, it also helps keep the battery charged more efficiently and reduces the risk of undercharging. This means that electrical components, like ignition and lighting, can work more reliably, improving overall vehicle performance and reducing the chances of electrical failures.
Available in 12-, 24-, and 48-volt models, the UPI series offers six different configurations ranging from 165 amps to 390 amps at output. See below for output curves by model: