Real hoursepower ?
10-14-2011, 12:28 AM
#21
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For a quickee calculator...that one works pretty decent. Of course it's not trying to correct for weather...and I think it's trying to show flywheel HP...not RWHP.
I threw in a few versions of mine and it's not too far off.
I freshened my pump gas 540 last year and turned it into a 555". Nothing was changed other than the bore size and a a 1/2 point additional compression. Same heads/cam,intake,carb etc.
The first dyno run before I changed anything was 861HP. That's 1.55 HP per cube.
So if it was making the same 1.55 HP per cube as a 540...then that would be about 837 HP...the added cubes increased power by 24 HP over whatever it was making as a 540..and whatever little bit the compression might have made. 15 cubes x1.55= 23 or so HP...so I guess the compression was 1 hp huh? The last time it was on a dyno as a 540with a different cam and oil pan it made 825.1 HP..so we're pretty consistent.
OK..so I go through all of this because that calculator indicates it was *showing* 838 HP at the 3750 weight it was running at on that particular 90* temp day when it ran 142 mph through the mufflers. Other runs I put through it showed a low of 820 HP on some really hot days...which is pretty decent for something you spend a few seconds sticking numbers in!
Doesn't answer the OP's original question... but gives some additional data for validation.
JIM
I threw in a few versions of mine and it's not too far off.
I freshened my pump gas 540 last year and turned it into a 555". Nothing was changed other than the bore size and a a 1/2 point additional compression. Same heads/cam,intake,carb etc.
The first dyno run before I changed anything was 861HP. That's 1.55 HP per cube.
So if it was making the same 1.55 HP per cube as a 540...then that would be about 837 HP...the added cubes increased power by 24 HP over whatever it was making as a 540..and whatever little bit the compression might have made. 15 cubes x1.55= 23 or so HP...so I guess the compression was 1 hp huh? The last time it was on a dyno as a 540with a different cam and oil pan it made 825.1 HP..so we're pretty consistent.
OK..so I go through all of this because that calculator indicates it was *showing* 838 HP at the 3750 weight it was running at on that particular 90* temp day when it ran 142 mph through the mufflers. Other runs I put through it showed a low of 820 HP on some really hot days...which is pretty decent for something you spend a few seconds sticking numbers in!
Doesn't answer the OP's original question... but gives some additional data for validation.
JIM
