This is the Traxxas TRX 3.3 Racing Engine with Pull Starter.

For use in all Traxxas TRX2.5 and TRX 3.3 equipped vehicles
Pull starter can be removed to install the EZ Start
60% more peak power than the TRX2.5, with nearly 50% more power
under the curve for strong linear acceleration
Round rear exhaust with one-piece IPS crankshaft
Composite body slide valve carburetor witt high-volume air filter
Blue anodized aluminum cooling head with molded head protector

Displacement: .20 cu in (3.3cc)
Practical RPM: N/A
Output: N/A
Weight: 10.9oz (305g)
Distance between mounting holes same side: 0.39" (10mm)
Distance between mounting holes opposite side: 1.2" (32mm)
Distance from center of engine to front bearing: 1.2" (32mm)
Distance/bottom of mounting flanges/top of cylinder head: 3.5" (88mm
Width of mounting flanges: 44mm