Ignition Coil + Iridium Spark Plugs for Mercedes Benz SLR McLaren (2005-2009) 5.5L

High-Output Ignition Coil and Iridium Spark Plug Service Kit for 2005-2009 Mercedes Benz SLR McLaren (C199)

What it Does: The complete ignition kit replaces degrading factory dual-output coils and twin-spark plugs on the 2005-2009 SLR McLaren to eliminate high-boost spark blowout and restore factory combustion efficiency across the supercharged V8 powerband.

The Stock Mercedes Benz SLR McLaren Secondary Ignition Breakdown

The hand-assembled M155 supercharged 5.4-liter engine relies on a dual-spark architecture utilizing eight dual-tower ignition coils firing sixteen plugs. Under elevated boost pressure and significant underhood thermal loading inherent to the front-mid mounted C199 chassis, OEM coil potting compounds suffer dielectric breakdown. Micro-cracking in the primary and secondary coil windings induces intermittent misfires, elevated secondary resistance, and erratic flame propagation under wide-open throttle. Concurrently, factory standard electrodes erode under sustained supercharged cylinder pressures, widening spark gaps, over-saturating the primary drivers, and causing unburned fuel to wash cylinder walls.

The Engineering Solution

This comprehensive ignition service kit supplies eight direct-fit dual-terminal ignition coils paired with sixteen pre-gapped Denso Iridium TT spark plugs (IKH20TT / 4704). Each ignition coil features high-dielectric epoxy potting and reinforced PBT housings engineered to withstand excessive radiant engine bay heat soak while maintaining continuous high-energy dwell under peak load. The included iridium-rhodium twin-tip plugs feature an ultra-fine 0.4mm center electrode and a 0.7mm platinum ground needle. This geometry reduces the necessary ionization voltage, eliminates high-cylinder-pressure spark blowout, and stabilizes idle and throttle tip-in without stressing the factory Bosch ME engine management system.

Technical Specifications

Compatibility

• 2005 Mercedes-Benz SLR McLaren Coupe 5.5L Supercharged V8 (M155)
• 2006 Mercedes-Benz SLR McLaren Coupe 5.5L Supercharged V8 (M155)
• 2007 Mercedes-Benz SLR McLaren 722 Edition / Coupe 5.5L Supercharged V8 (M155)
• 2007 Mercedes-Benz SLR McLaren Roadster 5.5L Supercharged V8 (M155)
• 2008 Mercedes-Benz SLR McLaren Roadster 5.5L Supercharged V8 (M155)
• 2009 Mercedes-Benz SLR McLaren Roadster 722 S 5.5L Supercharged V8 (M155)

Frequently Asked Questions

Does this fit the C199 SLR McLaren?

Yes, this is a direct fit for the 2005-2009 Mercedes Benz SLR McLaren equipped with the M155 twin-spark supercharged V8 engine.

Are plug wires included with this coil and spark plug kit?

No, this service kit includes eight dual-output ignition coils and sixteen iridium spark plugs; factory spark plug wires must be inspected and reused or purchased separately.

The Mercedes Benz Precision Caliber

Supercharged European powertrains require uncompromising ignition precision; installing factory-matched impedance coils alongside high-efficiency iridium plugs ensures zero misfire fault codes, clean lambda feedback, and instantaneous boost recovery.