The BMW ETK for the E30 is generally excellent, but it falls short when it comes to A/C part number references. This is especially true for M20-powered E30s, which were equipped with three different compressors – Bosch, Seiko, and Denso. While the Bosch and Seiko setups share the same A/C lines, the Denso configuration...
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Cheap keyless entry for a BMW E30 (LB-402 AliExpress or smaller LB-408): You can add keyless entry to an E30 for under ~$20 using an LB-402 keyless entry kit. The LB-402 (or LB-408) ties into the factory Central Locking Control Unit (CLCU) by triggering the E30’s lock/unlock request inputs. Where the E30 central locking...
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BMW Alpine CM5908 Radio Recap — Electrolytic Capacitor BOM (22 caps) Posted for posterity, referenced from R3v. If you’re rebuilding the amplifier section of the BMW Alpine CM5908 radio, a full electrolytic recap is one of the best “baseline repairs” you can do. Electrolytics age, drift, and dry out over time, which can lead...
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It’s become increasingly common for owners to convert early E30 M20 cars to the later-style radiator setup. However, that conversion requires a long list of additional parts—new hoses, mounting brackets, water pump, coolant crossover, expansion tank, and more. In reality, this conversion is completely unnecessary. The trend has largely been driven by the assumption...
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Sanden Compressor Conversions for M20-Powered BMW E30s M20-powered E30s were originally fitted with one of three air-conditioning compressors: Bosch, Seiko (largely identical to Bosch), or Denso. This guide specifically focuses on converting E30 M20 cars that were originally equipped with Denso 10P15E compressors to a Sanden compressor. The reason for this focus is the...
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These hose adapters allow you to install a Sanden SD508 / SD709 / SD7H15 / SD5H14 compressor on an M20 engine while retaining all factory A/C lines. This makes the Sanden a drop-in replacement (with appropriate bracket and belt). These require no modification to factory oil cooler lines or fuel cooler lines. Reference this...
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It only takes 3 screws to remove the bottom panel of a BMW CM5908 Radio. There you will find the code jumpers; these jumpers, based on how they are soldered determine the radio code. Note where the jumpers are numbered TDC-0 through 5: Jump only TDC-5 to set code 25142: *Pictured is TDC-2 jumped,...
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Lloyd mats offers a trunk mat pattern for the E30 that fits well overall. It appears to include a bit of extra material near the battery tray area—likely to accommodate E30s with batteries mounted in the engine bay. It’s not a major issue; just a slight trim is needed, and everything fits perfectly. Details:...
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*The following is likely to be almost identical for the KE-83 KBM, the 4 channel version of this 2 channel KE-81 KBM radio. Important Radio Security Code Considerations: Cassette Mechanism Belt Issue: Over time, the original factory cassette belts degrade into a soft, mushy substance. Attempting to operate the cassette mechanism in this state...
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With the widespread use of NGK V-Power spark plugs (NGK 5077 – ZGR5A) in E30 M20 applications, it’s important to stay vigilant about their replacement intervals. These plugs feature a smaller electrode surface area, which, while great for ignitability, tends to wear faster. As the electrode wears down, the spark plug gap increases, which...
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