aps Member 1,505 Member For: 21y 10m 14d Posted 23/02/05 11:26 AM Share Posted 23/02/05 11:26 AM Every time I post a fight breaks out soon after. macka<{POST_SNAPBACK}>Not a problem macka, just a healthy debate to verify facts. Peter Link to comment Share on other sites More sharing options...
badxr6 HEINRICH PERFORMANCE AND TUNING Donating Members 439 Member For: 20y 11m 12d Gender: Male Location: adelaide Posted 23/02/05 11:28 AM Author Share Posted 23/02/05 11:28 AM hereFair enough Bruce though why did you state 368 RWkW's about 3 posts back? Peterthe 368 was on a dyno with no shoot out mode the 390 was from the other two dyno dynamics onesOk that makes sense now, will be intersting to see what MPH your T runs in the future. Peter Link to comment Share on other sites More sharing options...
Turbo6man Lifetime Members 4,084 Member For: 22y 3m 10d Gender: Male Location: South Coast NSW Posted 23/02/05 11:29 AM Share Posted 23/02/05 11:29 AM In any event even taking the lower figure we can still equate that to being at least 450fwkw ...<{POST_SNAPBACK}>Please tell me how you figure that?Peter<{POST_SNAPBACK}>Mathematically ... can't you do it Peter? I know we've been down this road before but, what the heck, I'll go for another ride with you ...As most tuners/racers agree that a vehicle equipped with manual transmission will absorb between 15% and 20% of engine power - I have chosen the middle figure of 18% (rounded up from 17.5% for my simple sliderule).Thus 450 x 18% = 81 ;450 - 81 = 369.Now that to me is damn close to the 368 figure you used above while claiming the car couldn't make 450kW at the fly ...Your serve ... Link to comment Share on other sites More sharing options...
aps Member 1,505 Member For: 21y 10m 14d Posted 23/02/05 11:37 AM Share Posted 23/02/05 11:37 AM In any event even taking the lower figure we can still equate that to being at least 450fwkw ...<{POST_SNAPBACK}>Please tell me how you figure that?Peter<{POST_SNAPBACK}>Mathematically ... can't you do it Peter? I know we've been down this road before but, what the heck, I'll go for another ride with you ...As most tuners/racers agree that a vehicle equipped with manual transmission will absorb between 15% and 20% of engine power - I have chosen the middle figure of 18% (rounded up from 17.5% for my simple sliderule).Thus 450 x 18% = 81 ;450 - 81 = 369.Now that to me is damn close to the 368 figure you used above while claiming the car couldn't make 450kW at the fly ...Your serve ... <{POST_SNAPBACK}>Drive train loss is not a constant and definetly not a calculated % figure, if you really want to know power at the flywheel there is only one way to find out, it's called an engine dyno and has been for many years, this is how every car manufacturer on the planet measures engine power. Peter Link to comment Share on other sites More sharing options...
Guest Guests Posted 23/02/05 11:45 AM Share Posted 23/02/05 11:45 AM Please tell me how you figure that?Peter<{POST_SNAPBACK}>posibly like this?Macka, with all due respect, the maths you are reffering to is based upon flywheel, not wheel horsepower. From there, multiply that figure by 0.746 to convert to flywheel kW.Hope this helps clarify the the use of these formulas.George Link to comment Share on other sites More sharing options...
Turbo6man Lifetime Members 4,084 Member For: 22y 3m 10d Gender: Male Location: South Coast NSW Posted 23/02/05 11:49 AM Share Posted 23/02/05 11:49 AM In any event even taking the lower figure we can still equate that to being at least 450fwkw ...<{POST_SNAPBACK}>Please tell me how you figure that?Peter<{POST_SNAPBACK}>Mathematically ... can't you do it Peter? I know we've been down this road before but, what the heck, I'll go for another ride with you ...As most tuners/racers agree that a vehicle equipped with manual transmission will absorb between 15% and 20% of engine power - I have chosen the middle figure of 18% (rounded up from 17.5% for my simple sliderule).Thus 450 x 18% = 81 ;450 - 81 = 369.Now that to me is damn close to the 368 figure you used above while claiming the car couldn't make 450kW at the fly ...Your serve ... :smilielol:<{POST_SNAPBACK}>Drive train loss is not a constant and definetly not a calculated % figure, if you really want to know power at the flywheel there is only one way to find out, it's called an engine dyno and has been for many years, this is how every car manufacturer on the planet measures engine power. Peter<{POST_SNAPBACK}>Heard all that from you before - I was really hoping you'd have something new to bring to the debate.Now that you've stated this so clearly and succinctly why is it then that YOU and every other tuner in the place will put forward a figure for power at the fly calculated, or estimated if you like, from the dyno produced rwkw figures ... hmmm ... well, hmmmm ... ??? Link to comment Share on other sites More sharing options...
Turbo6man Lifetime Members 4,084 Member For: 22y 3m 10d Gender: Male Location: South Coast NSW Posted 23/02/05 11:58 AM Share Posted 23/02/05 11:58 AM (edited) Oh and just while I have my sliderule warmed up I did the calcs on the basis of your oft stated belief that driveline losses remain basically constant as power output from the engine increases. I have take the liberty for the purpose of this calculation to adopt the "new" figure of 390rwkw which you have now agreed the vehicle is making at the rears.So we have a standard T of 240kw showing around 190kw at the wheels. From you own published data for a manual car. A driveline loss therefore of 50kw. Take this from the claimed 450kw and even I don't need the sliderule to tell me it's 400kw. The graph says 390kw so ... close enough do you think?BTW a loss of just 50kw from an engine of 450kw equates to a driveline loss in percentage terms of just over 11. Do you honestly believe that this is realistic? Edited 23/02/05 08:14 PM by Forum Director Link to comment Share on other sites More sharing options...
Guest Guests Posted 23/02/05 12:14 PM Share Posted 23/02/05 12:14 PM (edited) no point in arguing ADMIN SNIPPlease note that abuse of fellow members is in breach of forum policy and is now an issue that we (each and every one of us) must clamp down upon. Members must be treated with the respect and common decency that we all demand and deserve. This simple demand is one that will make the forum a much more enjoyable place and one where all members will feel welcome to participate.I invite all to keep this in mind when posting - regardless of whether you agree or disagree (or in fact have misunderstood) the post you are responding to.Forum Director Edited 23/02/05 07:44 PM by Forum Director Link to comment Share on other sites More sharing options...
aps Member 1,505 Member For: 21y 10m 14d Posted 23/02/05 08:30 PM Share Posted 23/02/05 08:30 PM BTW a loss of just 50kw from an engine of 450kw equates to a driveline loss in percentage terms of just over 11. Do you honestly believe that this is realistic?<{POST_SNAPBACK}>Did you consider ther power loss to drive the dynamometer, I know what this power loss figure amounts to, do you? Peter Link to comment Share on other sites More sharing options...
JB Forum Superhero Donating Members 3,109 Member For: 21y 1m 25d Location: Eastern Suburbs of Mexico Posted 23/02/05 10:12 PM Share Posted 23/02/05 10:12 PM laws of physics dont add up do they it frustrats me as much as the next personThat's what I used to try to tell my physics teacher, but he seemed to disagree Link to comment Share on other sites More sharing options...
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