tattooed Posted August 26, 2008 Posted August 26, 2008 I'm using a "study guide" and came across a few "rules of thumb" I cannot find answers to. 1" = ?? LBS1" = ?? BHP Quote
67november Posted August 26, 2008 Posted August 26, 2008 is your 1" equating to manifold pressure? Quote
Helix Posted August 26, 2008 Posted August 26, 2008 Okay, I'm bored. Let's see here. 29.92" = 14.7psi on a standard day, so 1" equals about .49psi of atmospheric pressure. At wide open throttle at sea level 29.92" = 100% power, so 1" equals 3.34% power, which almost works out to the 8,000ft = 75% power at full throttle gouge. Now I need a nap. Quote
tattooed Posted August 26, 2008 Author Posted August 26, 2008 Okay, I'm bored. Let's see here. 29.92" = 14.7psi on a standard day, so 1" equals about .49psi of atmospheric pressure. At wide open throttle at sea level 29.92" = 100% power, so 1" equals 3.34% power, which almost works out to the 8,000ft = 75% power at full throttle gouge. Now I need a nap. huh? Now you really lost me. Yes, this is in regards to MAP.The 3rd "Rule of Thumb" was 1" = ?? feet....that's simple.... loose 1" MAP per 1,000. I don't know the other 2 I listed above. Quote
Guest pokey Posted August 26, 2008 Posted August 26, 2008 the old rule of thumb: one inch of manifold pressure was equivilent to SIX horsepower,,,,,,,AND one horsepower would lift 13.5 pounds while hovering,,,SO one inch of manifold pressure will lift about 80 pounds of payload my source ? AC 61-13 of korse ! i have tried this in my 300 long ago & found it to be quite accurate Quote
Helix Posted August 26, 2008 Posted August 26, 2008 huh? Now you really lost me. Yes, this is in regards to MAP.The 3rd "Rule of Thumb" was 1" = ?? feet....that's simple.... loose 1" MAP per 1,000. I don't know the other 2 I listed above.Sorry, I went with the inch I thought you were asking about, just woke up at the time. Too many variables. Quote
tattooed Posted August 26, 2008 Author Posted August 26, 2008 Sorry, I went with the inch I thought you were asking about, just woke up at the time. Too many variables. LOL OK, I figured it out. (Or at least the answers my school is looking for.....) "Rules of Thumb" 1" MAP for every 50 lbs (I agree with 80 lbs better) 1" MAP for every 7 BHP 1" MAP for every 1,000 feet elevation/altitude Quote
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