Hey guys, i'm new to this forum. I have a 1991 440 f/c Polaris Sport, that i'm suping the shit out of. I'm getting a single pipe for it that will add 8 HP. What is the stock HP on a 440 f/c engine?
Take the compression of both cylinders add them and devide by 2, multiply that by the motors max rpm and multiply that by the actual cc's, and then devide that by 6400000 and you should have your approximate HP (very close)
Welcome to the forum man. Should be around 50-60 somewhere in there.
I think that formula only works on twin sleds or divide the compression numbers added together by the number of cylinders perhaps, well atleast that is what I am thinking...
It works on singles/Twins/and tripples if done correctly - with a single just use the compression - with a twin and a tripple use the average compression. I got this formula from one of my snomobile magazines...... When I use it on my 91 Formula 470, I get 85.2 hp before adding the UFO's into it - so somewhere between 85 and 91hp.
mine seems a little off altho im not sure of the true hp of my sled. (was told 130-135) its almost/is the same spec. as a spx it has 135 psi in all cyls. the formula says it has 123 hp.
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