Traxxas Trx 2.5R Engine woth EZ starter motor and tunned pipe.

New engine missing original packaging

Slide carburetor provides less restrictive, straight through airflow for more power and better throttle response.
PowerTune head is machined from aluminum which promotes even heat distrubution for stable engine temperatures and rock-solid tuning
New sleeve for improved engine efficiency and better power.
Molded head protector prevents damage to the head and secures the glow plug wire.
Ultra-low restriction air filter provides superior air flow and filtration for more power and a long engine life.
Offset wrist pin further reduces piston slide loading for more even cylinder wear and longer engine life.

Displacement: 0.15 cu in (2.49cc)
Crankshaft Thread: 5mm (.197)
On-Center Mounting Holes, Front to Rear: 11mm (.433")
On-Center Mounting Holes, Side to Side: 31.4mm (1.24")
Back of engine(recoil)to front of drive washer: 73.2mm (2.88")
Height: 97.3mm (3.83")
Exhaust Port Diameter: inner - 9.9mm (.392") --- outer - 13.0mm (.512")"