AutoMeter Elite Pyrometer Gauge – 52.4mm | 0–2000°F EGT | Peak & Warn | Digital Stepper Motor | 3647

Watching your precise exhaust gas temperature can mean the difference between maximum performance and catastrophic engine damage. On high-output diesel or forced induction applications, there are few gauges more critical. AutoMeter’s Elite 3647 combines a Digital Stepper Motor display with high-definition LED backlighting for effortless EGT monitoring across the full 0–2000°F range — with programmable Peak recording and user-set Warn threshold alerts. The included Type K thermocouple assures maximum accuracy and minimum response time. Ships fast across Canada and the US.

Why EGT Monitoring Matters — Diesel and Forced Induction

Exhaust Gas Temperature (EGT) is the single most critical real-time thermal indicator for two specific powertrain applications:

• High-output diesel engines (primary application): Diesel engines are highly sensitive to sustained elevated EGT. Above approximately 1,250–1,350°F sustained at the pre-turbo measurement point, diesel engines risk piston crown damage, turbo wheel failure from overtemperature, head gasket compromise, and exhaust valve damage. This risk is heightened during towing at high load (sustained full throttle at low RPM), diesel drag racing, and sled pulling where EGT can climb rapidly and remain elevated. The 3647’s 2,000°F scale and programmable Warn alert give the driver immediate notification before reaching the thermal damage threshold. Applications: Ram 2500/3500 Cummins 6.7L, Ford F-250/350 Power Stroke 6.7L, GM 2500/3500 Duramax 6.6L, and modified diesel performance builds.
• Forced induction petrol/gasoline engines: Turbocharged and supercharged petrol engines produce significantly higher EGT than naturally aspirated equivalents under boost. Pre-turbo EGT on a high-boost petrol engine can reach 1,500–1,600°F under sustained wide-open throttle — a level that accelerates turbo heat soak and can indicate lean air/fuel conditions that risk detonation and piston damage. Real-time EGT monitoring provides a leading indicator of fuel mixture problems that may not be immediately apparent from other gauges.

Peak & Warn — Electronic Control Functions

The 3647’s electronic control interface provides two programmable functions that separate it from basic analogue EGT gauges:

• Peak recall: The gauge continuously records the highest EGT achieved during a session. At any point — or after the session — the driver can access the peak EGT reading to evaluate how close the engine came to the thermal limit. For towing calibration, this allows the driver to review the highest EGT achieved on a given grade or load condition and adjust driving technique or tune accordingly. For diesel drag racing and sled pulling, peak EGT is a key data point for tuning fuel delivery.
• Warn threshold: The driver programmes a specific EGT warn point — for example, 1,200°F for a street towing diesel. When live EGT exceeds this threshold, the gauge triggers an alert (audible and/or visual, depending on configuration). The warn function allows the driver to focus on driving and respond only when EGT reaches the programmed limit — rather than continuously scanning the gauge during a pull or tow.
• Electronic control interface: Both Peak and Warn functions are set and accessed via the gauge’s built-in electronic control — no separate control box or module required. The complete functionality is self-contained in the 3647 gauge unit.

Elite Series Construction — Digital Stepper Motor

The Elite 3647 uses AutoMeter’s Digital Stepper Motor (DSM) movement — the key technical distinction of the Elite series over AutoMeter’s lower gauge lines:

• Digital Stepper Motor vs traditional air-core: Conventional analogue gauges use an air-core or d’Arsonval movement driven by variable voltage or resistance from the sender. These movements are subject to needle hunting (oscillation around the true reading), slow response to rapid temperature changes, and inaccuracy at the extremes of the scale. The DSM drives the needle to a precise angular position using a stepper motor — eliminating hunting, providing faster needle response to temperature changes, and maintaining accuracy across the full 0–2000°F scale.
• High-definition LED backlighting: White gauge face with blue/white LED illumination — the Elite Series’ signature visual standard. Consistent, even illumination across the full dial face with no hot-spots. Clearly readable in direct sunlight and at night.
• 52.4mm (2-1/16") housing: The universal aftermarket gauge diameter. Fits all standard 2-1/16" gauge pods, A-pillar pods, overhead console pods, and dash cutouts. No adapter required for any standard gauge mounting position.

Type K Thermocouple — Included

EGT measurement requires a thermocouple — not a standard resistance temperature sender. The 3647 includes a Type K thermocouple probe:

• Type K thermocouple: Chromel/Alumel alloy junction — the most widely used thermocouple type for automotive EGT measurement. Accurate across a range well exceeding the 0–2000°F gauge scale. Type K is the industry standard for diesel EGT pyrometers — compatible probes and extensions are universally available if additional length or a replacement probe is required.
• Maximum accuracy and minimum response time: The thermocouple junction responds to temperature changes faster than resistance-based senders — critical for EGT monitoring where temperature can rise rapidly during a diesel pull or boost event.
• Installation requirement: The thermocouple probe mounts in the exhaust stream via a threaded bung. Most modified diesel trucks have a pre-turbo bung location already present; stock trucks require a bung to be welded into the exhaust manifold or downpipe. The 3647 includes installation hardware and multiple mounting options to simplify fitment.

Universal 52.4mm (2-1/16") fit. 0–2000°F EGT range. Digital Stepper Motor. Peak recall and programmable Warn threshold. Type K thermocouple included. Exhaust bung required for probe installation — not included. Diesel and forced induction applications. 1 lb.

Specifications

• Brand: AutoMeter
• Part Number: 3647
• Series: Elite
• Gauge type: Pyrometer (Exhaust Gas Temperature — EGT)
• Diameter: 52.4mm (2-1/16")
• Measurement range: 0–2000°F
• Movement: Digital Stepper Motor (DSM)
• Illumination: High-definition LED — white face
• Sender/probe type: Type K thermocouple
• Thermocouple: Included
• Peak function: Yes — programmable peak recall
• Warn function: Yes — programmable warn threshold
• Electronic control: Built-in — no external module required
• Application: Universal — diesel, forced induction, race
• Exhaust bung: Required for probe installation — not included
• Weight: 1 lb