LIQUI MOLY Lead Substi­tute 250ml › LM1838

LIQUI MOLY Lead Substitute 250ml – Classic Porsche Unleaded Petrol Additive

LIQUI MOLY Lead Substitute is a specialist petrol additive developed to protect older engines originally designed to operate on leaded fuel. Its protective formula lubricates non-hardened valve seats, reducing wear and helping maintain engine compression when using modern unleaded petrol.

Fits:

• Porsche 911 1965-1968 2.0L / 912 SWB (F)
• Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
• Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
• Porsche 924 2.0L 1976-79
• Porsche 924 2.0L 1980-85
• Porsche 928 4.5L 1978-82
• Porsche 928S 4.7L 1981-83
• Porsche 356 1950-55
• Porsche 356A 1955-59
• Porsche 356B 1959-63
• Porsche 356C 1963-65
• Porsche 914 (1970-1976)
• Porsche 912E 4CYL 1976

Ideal for appropriate classic Porsche engines, it also helps clean intake valves, combustion chambers and fuel preparation systems, supporting reliable engine operation and long-term protection.

What Does LIQUI MOLY Lead Substitute Do?

Lead Substitute provides protective lubrication for valve seats originally designed to benefit from leaded petrol. It helps prevent valve seat recession, reduces cylinder head wear and maintains compression in older petrol engines.

Why Do Classic Engines Need Lead Substitute?

Some older petrol engines were manufactured with non-hardened valve seats that relied on the protective properties of leaded fuel.

Using unleaded petrol without suitable protection can increase valve seat wear, potentially causing reduced compression, poor performance and eventual cylinder head damage.

When Should It Be Used?

Lead Substitute should be used when operating a classic petrol engine originally requiring leaded fuel and fitted with valve seats that have not been upgraded for unleaded petrol.

For continuous protection, LIQUI MOLY recommends adding the correct quantity at every refuelling.

Many Porsche engines already have suitable valve seat materials or have been upgraded during restoration. Check the original engine specification and cylinder head condition before use. Lead Substitute is generally unnecessary for engines designed to operate on unleaded petrol.

The product does not increase the octane rating of petrol and is not a replacement for the correct fuel grade.

Key Features

• Protects non-hardened valve seats against premature wear.
• Helps prevent valve seat recession.
• Supports consistent engine compression.
• Reduces the risk of cylinder head damage.
• Helps clean intake valves and combustion chambers.
• Designed for classic engines originally requiring leaded petrol.
• Compatible with retrofitted catalytic converters.
• Contains no organometallic compounds.
• Convenient measuring dispenser for accurate dosing.

Application Instructions

• Add Lead Substitute directly to the petrol fuel tank before refuelling.
• Use 25ml for every 25 litres of unleaded petrol.
• Maintain the recommended mixing ratio of 1:1,000.
• One 250ml container treats up to 250 litres of petrol.
• Repeat at every refuelling where continued valve seat protection is required.

Important: Avoid underdosing or overdosing. Always use the correct petrol octane rating recommended for the engine.

Product Category Description – Classic Porsche Lead Replacement & Fuel Additives

LIQUI MOLY Lead Substitute provides essential valve seat protection for classic Porsche petrol engines originally designed to operate on leaded fuel. Its specialised formula helps reduce valve seat wear, maintain compression and protect older cylinder heads when using modern unleaded petrol.

Suitable for consideration in classic Porsche 356, 911, 912, 914 and other early petrol engines requiring lead replacement protection, it offers a convenient maintenance solution for original, unrestored and period-correct engines.