Mazda Miata B6 1.6L L4 Engine 12498E 1989-1990

Short-nose crankshaft keyway deformation and hydraulic lash adjuster aeration induce severe ignition timing flutter on vintage sports cars. The Mazda Miata B6 1.6L L4 Engine 12498E eradicates harmonic damper wobble across this commercial long block repower. This 4-Cylinder 116HP DOHC powerplant requires front crankshaft bolt thread locking compound application before torquing the timing sprocket.

ASTM A48 Class 30 gray iron forms the closed-deck cylinder block marked with B6 and 6 casting stamps. A precision-machined forged steel crankshaft connects to cast aluminum pistons and drop-forged connecting rods riding on tri-metal bearings. This Mazda engine core demands a 12V 135A starter draw during sub-zero test cranks. Dry weight measures 180 lbs within a 22in length, 21in width, 24in height stance holding 3.8 quarts of oil.

Key Features of Mazda Miata B6 12498E

Classic roadster specialists buy Mazda Miata B6 1.6L L4 Engine 12498E inventory to eliminate crankshaft snout runout failures. Every industrial engine rebuild includes precision-machined crankshaft keyways and ultrasonic-cleaned hydraulic lash adjusters to eliminate valvetrain tick.

- Cylinder bores measure 3.071in with diamond plateau hone surface textures.
- Main bearing journal clearance holds at 0.0013in across the five-bearing iron block.
- Upgraded crankshaft snout keyways prevent woodruff key shear under rapid throttle changes.
- Dual overhead camshaft lobes undergo Rockwell C 58 hardness verification.
- Multi layer steel head gaskets eliminate combustion deck coolant leakage.
- This B6 commercial core features cylinder head decks surfaced flat to 0.0003in.
- Induction-hardened valve seat inserts resist unleaded gasoline recession wear.

Dynamometer Load Verification Bench

Controlled brake cell testing verifies that this B6 long block engine produces 116 continuous BHP and 100 ft-lbs of torque at 5500 continuous load RPM. Internal oil gallery pressure measures 50 PSI while oil sump temp settles at 190°F under sustained brake loading. Exhaust gas temp tops at 1250°F down the test header tubes. Individual cylinder compression reads between 175 PSI and 182 PSI across all four chambers. Crankshaft center journal runout holds within 0.0002in TIR.

Chassis Installation Application Boundaries

Clutch slave cylinder release forks require 5 lbs of pushrod pull force for positive release bearing clearance. This longitudinal engine is not engineered for front-wheel-drive transverse swaps, supercharged drag racing, or stationary sawmill saw drives.

- Drain initial break-in petroleum motor oil after 500 miles or 25 operating hours.
- Bleed hydraulic lash adjusters in clean engine oil prior to camshaft installation.
- Torque cylinder head fasteners in two stages to 56 ft-lbs final specification.

Commercial Protection Crate Manifest

Backed by our rigorous Mazda assembly standard, this remanufactured motor carries a 3-Year 100,000-mile parts warranty. The wood crate houses the complete long block core, stamped steel oil pan, front timing cover, aluminum valve cover, oil pickup tube, and signed dyno verification documentation.