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Bore: 83mm

Stroke: 91mm

Piston speed: 4776 (ft/min)@ 8000rpm or 24.26(meters/sec) @ 8000rpm

Rod length: 151.892mm or 5.98in

Rod weight (2jz): 757 grams

Piston weight (2jz): 377 grams

Piston pin weight (2jz): 133 grams

Piston rod combo wt (2jz): 1267 grams or 2.793 lbs

Rod bolt diameter: 10mm x 2

so, at 8000rpm, a piston rod combo weighing close to the 2jz setup applies a force of 1982.375 psia to the rod bolts. does this sound ok?Fc = mv2/r, where Fc = centrifugal force, m = mass, v = speed, and r = radius.

To perform the calculations we have estimated that the piston rod combo has mass of 1.267 kg, the radius of the circle (Crank throw) is 45.5 mm, which is 0.045 meters, and the rotational speed is 38.11 meters per second 8000rpm. each crank revolution covers Pi*D, or 3.14*91mm=285.88mm per Rev. 0.28588 meters * 8000 revolutions=2287 meters. if you can cover 2287 meters in one minute, then you cover 38.11 meters in one Second.

Step 2: The centrifugal force is calculated (see calculation below) to be 2146.016 Newtons.

Centrifugal Force = [Mass x (Velocity*2)]/Radius=Force in Newtons

Fc = {1.267 (kg) * {38.11 (m/s)}2}/ 0.045(m) = 2146.016 (N)

This force of 2146.016 Newtons is applied to two rod bolts of 10mm diameters each. the Cross sectional surface area of a 10mm bolt is 78.5sq.mm, or 157sq.mm total. Force applied = 2146.016N/157sq.mm to get this into standard units, or zeroed out to Lowest common denominator, i would divide 2146.016 by 157sq.mm and come out with 13.668 Newtons per square millimeter. If i convert 13.668 N/mm2 to PSIa, it comes out to be 1982.375.

thanks

chris