I dont know if anyone even cares, but if you are building an engine these are just a few formulas that can help you out.

Pi=3.1415927
pi/4= .7853982

Cylinder Volume= (pi/4 x (bore x bore) x Stroke)

Stroke= Displacement/(pi/4 x (bore x bore) x number of cylinders)

Bore= square root of,(displacement / (pi/4 x stroke x number of cylinders)

Metric Displacement (cc)= (pi/4 x (bore x bore) x stroke x number of cylinder) / 1000

Calculating Compression Ratio= (cylinder volume+chamber volume) / (chamber volume)

Chamber volume= (Cylinder volume) / (comprssion ratio -1.0)

Adding Gasket Thickness- Apply formula for cylinder volume using the gasket thickness in place of the stroke.

Milling= (Displacement ratio) / (cylinder volume)

There will always be 1 less combustion chamber volume than compression ratio.

Also if you are looking to mill you head you can use this next formula to find out how much to mill

(New disp. ratio - old disp. ratio) / (New disp. ratio x old disp. ratio) = (x) x stroke

if the formula is done in inches multiply the final answer by 25.4 to convert to millimeters

Mean piston speed(fpm)= (2 x stroke in inches x rpm) / 12
or
(stroke in inches x rpm) / 6

Rev limits= Piston speed(fpm) x 6 / (stroke) in inches

Horsepower= (Rpm x torque) / 5252

Torque= (5252 x horsepower) / Rpm

Bhp loss in relevence to elevation= (Elevation in feet x .03 x bhp at sea level) / 1000

long story short for the elevation is that you lose around 3 percent of your power per 1000 feet above sea level. Im not sure if it really helps but its kinda cool to know. If there are any other formulas that you would be intrested in please just let me know.

 

good info.

so say if you could drive on top of mt. everest (elev. 29,000 ft).. you would lose 87% of your net power?

 

exactly why the climbers are incredible athletes and wear oxygen. it's hard for your body to function with 87% of it's power gone :D

 

Yes lol and if some how a 70bhp civic got ontop of my everest it would be running something around 9.1bhp

 

Wow awesome information