DISCLAIMER
We recommend any conversions and/or modifications be performed by someone qualified to do so. Also, note that any modifications to an alternator will likely void the manufacturer’s warranty. Proceed at your own risk.
WHY UPGRADE?
The factory system outputs a tiny 50-60 amps of current max. Although this is generally enough for most people, some who use the car for leisure activities like 4wding and camping may require a larger capacity to service their 12v needs. In most cases, the inefficiency of the factory alternator can be demonstrated with a multimeter at the battery and the headlights on high-beam. You will likely see a significant drop in voltage as the alternator fails to keep up with the load at idle.
We went to great lengths to investigate some known upgrade options and find any new alternatives that may exist. 3 possible options were found to suit both Subaru L-series and Brumby. These are outlined below:
OPTION 1: NISSAN MAXIMA ALTERNATOR
(Direct fit with the least modifications. Pulley swap and custom spacer required)
DETAILS: Nissan Maxima alternator 90amp
FROM WHAT: Alternator from a VG30E, 86-94′ Nissan Maxima. (Notes: Must be from the SOHC engine only. NOT to be confused with a DETT or DET from 300z or 300zx, and also NOT from a VG30DE engine which is also DOHC.
PART NUMBERS: OEX part number HXA028 (tested) or JAS part number ANJ042 (tested). Plug adaptor part number E38-2022. Plug part number E38-201.
WHAT IT FITS: L-series and Brumby with and without Aircon. (Dual pulley L-series not tested)
MODS REQUIRED: Pulley requires swapping from the original EA alternator. A spacer is also required for the pulley to clear the body of the alternator. (Spacer size depends on the brand of alternator, 11mm for OEX brand and 8mm for JAS brand were tested). We highly recommend getting the spacer professionally made, even the smallest imperfection can cause the pulley to wobble and affect belt life. No mods to the casing are required. 2 pin plug adaptor is required (RP19 – RP15 PN#E38-2022) or remove the plug and use crimp connectors. (see wiring info at the bottom of the page) Flare the old battery lug connector and upgrade or add a second power output via a fuse to the battery positive is recommended.
RRP PRICE: $450 – $535 (Alternator Only)
OPTION 2: NISSAN PATROL/NAVARA ALTERNATOR
(May not direct fit due to it being slightly larger, no pulley swap required)
DETAILS: Nissan Patrol/Navara 100amp (dual pulley)
FROM WHAT: Nissan patrol GQ Y60, Y61 with TB42, TB45E engine. Also Nissan Navara D21 with KA24E engine and Nissan Navara D22 with VG33E engine.
PART NUMBERS: OEX part number HXA058 (tested) JAS part number ANJ414 (not tested)
POSSIBLE ALTERNATIVES NOT TESTED: OEX HXA024 (70amp), HXA076 (90amp), BXH1225N, ANJ038, AED 098-09-740, HXA067.
WHAT IT FITS: L-series and Brumby without Aircon (including dual pulley L-series). Extra mods are required with EA81 models with AC due to extra width between bolt-on points. NOTE: Not a direct fit as there is 1mm difference between the mounting hole to pivot point. The mounting hole also has a 2mm larger diameter which does not pose an issue.
MODS REQUIRED: Pulley does not require swapping however the Brumby models with AC may require the outer pulley rib to be cut off. (Relatively easy job) Minor mods to the casing may be required at bolt-on points. 2 pin plug adaptor is required (RP19 – RP15 PN#E38-2022) or remove the plug and use crimp connectors. (see wiring info at the bottom of the page) Flare the old battery lug connector and upgrade or add a second power output via a fuse to the battery positive is recommended.
RRP PRICE: $350 – $370 (Alternator Only)
OPTION 3: NEWER EJ SERIES SUBARU ALTERNATOR
(Most mods required to the casing, pulley swap required)
DETAILS: Subaru EJ series mounted upside down. (70amp – 110amp)
FROM WHAT: Subaru EJ engine series (various models)
PART NUMBERS: (not all combinations tested) Large 2 Pin plug (90 amp): JAS ARJ075, 098-09-701, HXA079 OEX 90A, Plug adaptor part number E38-2022. Plug part number E38-201. Round 4 pin plug (70 amp): 098-09-732, ANJ039 JAS 70a , BXH1226N BOSCH 70a, HXA025 - OEX 70A. Plug part number E38-2000. Small 3 Pin plug (90 – 110 amp): 098-09-742, ANJ403 JAS 90a, MXA2044 - OEX 110A, MXA308 - OEX 90A. Plug part number E38-2003
WHAT IT FITS: L-series and Brumby with and without Aircon. (Dual pulley L-series not tested).
MODS REQUIRED: Pulley requires swapping from original EA and spacer required. (Spacer size depends on brand of alternator and type. Ours required a 7mm spacer). This pulley will foul on the alternator casing and some careful filing/grinding will be required to the front housing of the alternator. Factory 2 pin plug re-wire required. Change plug or cut plug off and use crimp connectors. (see wiring info at the bottom of the page) Flare old battery lug connector and upgrade or add a second power output via a fuse to the battery positive is recommended. DANGER: Battery post on the alternator is dangerously close to the engine. This will require extra precautions when fitting. An insulating boot and/or a larger drive belt may be required. A short circuit between these points can cause significant electrical damage and/or fire.
RRP PRICE: Variable depending on model $300 – $500 (Alternator Only)
EXTRA NOTES
If all the information above has scared you off the idea of upgrading your charging system the recommended factory option is the HXA038 (OEX ALTERNATOR 12V 50A).
IMPORTANT NOTE: ** It is recommended that you upgrade the power charge wire between the alternator main power lug and battery via a large fuse. Due to extra load, the tension of the alternator belt may need to be tighter than usual to avoid belt slip. This tension can sometimes result in some additional minor belt noise.
The factory EA wiring colours are as follows:
EA81 = Black/White Sense (Battery positive) White/Red (Battery Light)
EA82 = Black/White Sense (Battery positive) Yellow/Red (Battery Light)
If you find your battery is going flat over a few days, it can be possible that the battery “Sense” is drawing power when the engine is off. This is particularly common with the round plug EJ alternators. In this case, the “Sense” wire may need to be wired to IGN+ instead of the EA “sense” which is permanent BAT+ on the factory Alternator harness.
The plug configurations for the different alternators are as follows:
