Enthalpy stated this formula in the past for 4 cylinders engines
XXXcc injectors * 0.666666666 = wheel horsepower
e.g. 370cc * 0.66666666 = 247rwhp
e.g. 480cc * 0.66666666 = 320rwhp
e.g. 550cc * 0.66666666 = 367rwhp
e.g. 555cc * 0.66666666 = 370rwhp
e.g. 600cc * 0.66666666 = 400rwhp
e.g. 620cc * 0.66666666 = 413rwhp
e.g. 650cc * 0.66666666 = 433rwhp
e.g. 660cc * 0.66666666 = 440rwhp
e.g. 680cc * 0.66666666 = 453rwhp
e.g. 700cc * 0.66666666 = 467rwhp
e.g. 720cc * 0.66666666 = 480rwhp
e.g. 740cc * 0.66666666 = 493rwhp
e.g. 750cc * 0.66666666 = 500rwhp
e.g. 800cc * 0.66666666 = 533rwhp
e.g. 850cc * 0.66666666 = 567rwhp
e.g. 900cc * 0.66666666 = 600rwhp
e.g. 950cc * 0.66666666 = 633rwhp
e.g. 1000cc * 0.66666666 = 667rwhp
Keep in mind that injectors don't always flow what they are rated. The only real way to tell is to get them tested. I had my SARD 850cc injectors tested by Dave at DeatschWerks (
http://www.deatschwerks.com), a sponsor on this site. The results were that they were indeed 850cc injectors and that they were very closely matched.
Victor