Sports Car Forum - MotorWorld.net - View Single Post - [REQUEST] Information or links to literature on engines

number77 · 02-23-2005, 08:17 PM

so your trying to measure the efficiency? there is tons of info on this on the net. probably more than he want lol. some basics are--- there is a temperature for your engine to run most efficiently at. ifs not the coolest temperature either. even on a hot day you have to let a car "warm up"
there is a thing called volumetric efficiency, which has to do with getting air/fuel in the cylinders. you have reached 100% VE (you won't have this in a stock naturally asperated car) when the atmospheric pressure inside the cylinder is the same as the outside of the car.
turbos/superchargers assist the engine in become more efficient at producing power and increase the VE to beyond 100%
heres a link with some info
http://www.tpub.com/content/engine/14075/

also, iron blocks make more power than aluminum ones because they retain heat. the aluminum cools very quickly in comparison and makes the engine less efficient.

you cannot accurately predict hp loss to friction.
here is a link of a convo i was a little part of
http://web.camaross.com/forums/showt...0&page=1&pp=15
he has measured the power at the rear wheels and flywheel. to you can subtract to get a frictional loss.

02-23-2005, 08:17 PM	#5
number77 Regular User Join Date: Feb 2004 Posts: 305	so your trying to measure the efficiency? there is tons of info on this on the net. probably more than he want lol. some basics are--- there is a temperature for your engine to run most efficiently at. ifs not the coolest temperature either. even on a hot day you have to let a car "warm up" there is a thing called volumetric efficiency, which has to do with getting air/fuel in the cylinders. you have reached 100% VE (you won't have this in a stock naturally asperated car) when the atmospheric pressure inside the cylinder is the same as the outside of the car. turbos/superchargers assist the engine in become more efficient at producing power and increase the VE to beyond 100% heres a link with some info http://www.tpub.com/content/engine/14075/ also, iron blocks make more power than aluminum ones because they retain heat. the aluminum cools very quickly in comparison and makes the engine less efficient. you cannot accurately predict hp loss to friction. here is a link of a convo i was a little part of http://web.camaross.com/forums/showt...0&page=1&pp=15 he has measured the power at the rear wheels and flywheel. to you can subtract to get a frictional loss.