DENSO 4509 Platinum TT Spark Plug - PTF16TT

The DENSO 4509 Platinum TT spark plug features a revolutionary twin-tip design that delivers more efficient combustion for improved engine performance, power output, and fuel economy. This premium spark plug originated from DENSO's advanced Super Ignition Plug (SIP) technology, featuring a titanium-enhanced twin-tip design previously found only in the most technologically advanced OEM applications.

Key Features:

• 1.1mm platinum alloy center electrode and 1.1mm titanium-enhanced ground electrode for maximum durability
• 360-degree laser weld construction with free-standing firing pad design
• Purified alumina powder insulator provides exceptional dielectric strength and thermal conductivity
• Five-rib insulator design prevents flashover
• Machine rolled threads prevent seizing or cross-threading during installation and removal
• 100% pre-fired to ensure highest quality
• Copper-glass seal bonds center electrode and insulator for gas-tight seal

Technical Specifications:

• Thread Size: 14mm with 11.60mm (0.457 inch) reach
• Seat Type: Tapered seat
• Part Number: PTF16TT
• Recommended Torque: 7-15 lb-ft for both cast iron and aluminum cylinder heads

DENSO pioneered the use of platinum in spark plug manufacturing, applying this precious metal to both center and ground electrodes to maximize longevity and provide superior resistance to erosion and corrosion. This design delivers low required firing voltage and higher ignitability for better mileage, increased power, fewer misfires, faster starts, and minimized spark gap growth throughout the plug's service life.

Replaces OEM part numbers including Ford ASF42P, ASF42C, ASF42, ASF52, Chrysler 4289155, and numerous GM part numbers including 19208523, 19300383, 19300873, 19301654, and 19302742.