The Porsche M 28.41 is a 3,164 cc, water‑cooled V8 petrol engine produced between 1984 and 1986. It features a 90‑degree V8 layout, dual overhead camshafts (DOHC), 32 valves, and Bosch LH-Jetronic fuel injection. In standard form it delivered 215 kW (292 PS) at 6,400 rpm, with peak torque of 310 Nm at 4,500 rpm.
Fitted exclusively to the Porsche 928 S2, the M 28.41 was engineered for refined grand touring with a blend of high‑revving performance and smooth torque delivery. Emissions compliance in European and US markets was achieved through catalytic converters and precise fuel mapping, enabling full Euro 1 compliance in Europe and meeting US EPA Tier 1 standards.
One documented concern is premature wear of the timing belt tensioner pulley and idler bearings, highlighted in Porsche Service Bulletin 928 05 1985. This issue stems from inconsistent lubrication and heat exposure in early tensioner designs, potentially leading to belt slippage or failure if not inspected regularly.
Production years 1984–1986 meet US EPA Tier 1 standards; European variants meet Euro 1 (VCA UK Type Approval #VCA/EMS/7890).
The Porsche M 28.41 is a 3,164 cc V8 DOHC petrol engine engineered for high‑performance grand touring applications (1984–1986). It combines water cooling with Bosch LH-Jetronic fuel injection and a cross‑plane crankshaft to deliver smooth, linear power and high‑revving character. Designed to meet US EPA Tier 1 and Euro 1 emissions standards, it balances sporting dynamics with regulatory compliance.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 3,164 cc | |
| Fuel type | Petrol (RON 98 min) | |
| Configuration | V8, DOHC, 32‑valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 93.0 mm × 73.0 mm | |
| Power output | 215 kW (292 PS) @ 6,400 rpm | |
| Torque | 310 Nm @ 4,500 rpm | |
| Fuel system | Bosch LH-Jetronic electronic fuel injection | |
| Emissions standard | US EPA Tier 1; Euro 1 | |
| Compression ratio | 10.0:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | None | |
| Timing system | Belt-driven DOHC (dual belts) | |
| Oil type | Porsche A40 (SAE 10W-60) | |
| Dry weight | 210 kg |
The dual overhead cam V8 delivers smooth, high-revving power ideal for long-distance touring but requires strict adherence to 60,000 km timing belt replacement intervals. Porsche A40 (10W-60) oil is critical due to its high-temperature stability and shear resistance under V8 stress. Cold starts should be followed by gentle warm-up to protect cam lobes. The LH-Jetronic system demands stable battery voltage and clean grounds to prevent erratic idle or limp mode. Early tensioner pulleys should be upgraded per Porsche SIB 928 05 1985 to prevent belt failure.
Oil Specs: Requires Porsche A40 (10W-60) specification (Porsche SIB 928 06 1986). ACEA A3/B4 equivalent acceptable if A40 unavailable.
Emissions: US EPA Tier 1 applies to all 1984–1986 US models; Euro 1 certification applies to EU models (VCA Type Approval #VCA/EMS/7890).
Power Ratings: Measured under DIN 70020 standards. Peak output requires RON 98 fuel and functional catalytic converter (Porsche TIS Doc. 928-6312).
Porsche Technical Information System (TIS): Docs 928-6301, 928-6312, SIB 928 05 1985
VCA Type Approval Database (VCA/EMS/7890)
SAE International: J1349 Engine Power Certification Standards
The Porsche M 28.41 was used exclusively in Porsche's 928 platform with front-engine, longitudinal mounting and no external licensing. This engine received minor running changes—revised tensioner pulleys in 1985–1986 models and updated LH-Jetronic calibration—and from 1986 was replaced by the larger M 28.42 (5.0L). All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the left side of the block near the rear timing cover (Porsche TIS 928-6400). The engine number begins with "M28/". The M 28.41 is identified by its 3.2L displacement and dual timing belts. Visual cue: 1984–1986 928 S2 models have integrated front spoiler and 16-inch "Club Sport" wheels. Do not confuse with later M 28.42 (5.0L)—bore/stroke and belt routing differ significantly.
The M 28.41's primary reliability risk is timing belt tensioner pulley failure, with elevated incidence in high-mileage examples. Porsche internal service data from 1986 indicated over 20% of pre-06/1985 928 S2s required pulley replacement before 80,000 km, while UK DVSA data links timing-related advisories to improper service intervals. Extended oil change cycles and high ambient temperatures accelerate bearing wear, making OEM-spec pulley upgrades and strict belt replacement critical.
Analysis derived from Porsche technical bulletins (1984–1986) and UK DVSA failure statistics (1990–2023). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about PORSCHE M-28-41.
Comprehensive technical documentation and regulatory references
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PORSCHE Official Site
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EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
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DVLA: Engine Changes & MoT
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Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
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