Harley Davidson Evolution Compression

The engine isnt built full tilt.

Harley davidson evolution compression. The larger 1340 Evolution engine has a maximum HP of 58 at 5000 RPM and a top speed of 1025 MPH. To download our Evolution Big Twin machining services catalog or our head work sheet click here. To give that CNC finish on heads and cylinders.

This what a stock EVOLUTION combustion chamber looks like with stock sized valves. If the engine doesnt detonate and cranks good I would be ok with those numbers. When the engine is assembled use one of the 030 inch thickness head gaskets instead of the normal 040 or 060 inch gaskets.

This carburetor had been modified using a standard DynoJet re. Air-cooled Evolution Displacement 883 cm3 Bore X Stroke 30x38 in OR 76 mm Compression Ratio 881 Horsepower 536000 KWhpRPM Torque 494100 lb-ftRPM OR. Trending at C 38743.

However the heads have to come off and be drilled to install them unless theyre SS heads that are machined and plugged for them. The 1100 Evolution engine has a predictably higher maximum HP of 50 at 5500 RPM with a top speed of 1019 MPH. Harley-Davidsons Evolution engine--- frequently referred to by riders as an Evo or Blockhead engine --- fueled increases in Harley-Davidsons overall sales and stock price for over 20 years after it first entered the motorcycle market in 1984The small Evolution engine permanently replaced the Ironhead engine and as of November 2010 is still being produced by the Harley-Davidson.

I would guess the average stock EVO maybe has 150 psi of compression. This is considered the minimum compression ratio needed to make serious power from a. You dont need to machine the heads as deep as if you were using OEM.

Others that have owned EVOs may chime in. Kirby is in FLorida. 1340 FORGED PISTONS - 1051 010.