RHR BOOST Moderating Team 5,698 Member For: 21y 5m 21d Gender: Male Location: Southern Highlands NSW Posted 26/10/06 04:43 AM Share Posted 26/10/06 04:43 AM I have to admit that I also think that after 5000rpm my car doesnt feel like its pulling as well as it does prior..As for the manual VS Auto.. I really enjoy my manual when driving through the twisties. What does annoy about the manual is stop start traffic. I have also driven the auto six speed and its feels great. Link to comment Share on other sites More sharing options...
Mildman Member 149 Member For: 19y 3m 15d Posted 26/10/06 04:49 AM Share Posted 26/10/06 04:49 AM Thinking further - what use is a quoted power figure? I can be very misleading to the performance of a car.All it tells you is how far into the rev range the engine can hold torque. I guess then power tells you how quickly to torque curve drops off....but it can be very easily manipulated by achieving a very high gradient torque curve at high rpm - which will have no relation to the cars ability to accelerate.Why do we use power to compare the performance of cars? Link to comment Share on other sites More sharing options...
Ralph Wiggum Moar Powar Babeh Lifetime Members 19,323 Member For: 19y 5m 3d Gender: Male Location: Perth Posted 26/10/06 05:10 AM Share Posted 26/10/06 05:10 AM (edited) quote "horsepower sells engines...torque wins race" we sell them like that because horsepower is easier to sell than torque. I suppose it easier to digest than torque figures...after all torque is a quanitfiable force, horsepower is only a unit of measure (x amount of work in x time ,cant remember the exact figures). Joe public doesnt want to tell his rev head mates that his car makes 650nm from 2000 rpm to 4800rpm(and will hand them there arse in a drag) he wants to them them it 270kw's cause horse power is king remember... Edited 26/10/06 05:14 AM by hiddeous Link to comment Share on other sites More sharing options...
Mildman Member 149 Member For: 19y 3m 15d Posted 26/10/06 05:25 AM Share Posted 26/10/06 05:25 AM (edited) ...and so the house of cards I had so carefully built falls.Time to put my car on a dyno and work out where torque drops off, till then I start changed at 4500rpm, not 5500rpm and try and quantify the distance.I only found out through testing on my PDAs' acceleration software, bit thinking got me to the testing point.. Although Hp and Torque cross at 5252rpm. What software is that by the way? Edited 26/10/06 05:26 AM by Mildman Link to comment Share on other sites More sharing options...
replicant Member 180 Member For: 19y 3m 17d Posted 26/10/06 05:53 AM Share Posted 26/10/06 05:53 AM Well actually here's the other thing... the delivery of the torque matters too. In a BF XR6T, you are essentially getting close to 90% of maximum torque from about 1350 rpm all the way to about 5000 odd - which gives it a very linear power curve. The fact that the turbo allows those characteristics means that it's really useable all the time, especially if you tow something like a boat or you suddenly go from 10-15% TPS to 100% when you need to accelerate... in the old days of highly tuned NA engines and Weber dual throats, we'd have said it's always on the cam...Now the Boss 290 in the GT has a higher overall power number 290kW vs 245kW (and I think it's got a better overall torque number) but it doesn't get to about 90% of its torque until you have dialled up about 3750rpm and the torque band is from about 4 grand to 5 and one half grand... outside of the that, the breathing characteristics of the twin cam heads means that it ain't particularly torquey... which means that you have to rev the thing all the time and row the 'box to get the best performance.Ironically, in the days of the EB - the pushrod Windsor 5.0 litre HO which made 164kW had low down torque and was easy to drive and the XR6 motor which had the split exhaust and the interesting heads made 161kW and you had to keep it stirred...On the other hand, you can get some astronomical torque numbers out of a common rail turbo diesel and they usually have a torque curve that you could use as a straight edge - trouble is that they sound awful and the thing is asthmatic past four grand despite more optimistic rev limits...The other point to note is that electric engines have close to maximum torque at 0 rpm (so keep that in mind when you think of hybrids) and are only surpassed by steam engines... now you may think of steam technology as ancient but they still rely on steam power to get planes off aircraft carriers using the catapults and... nuclear energy is essentially steam power... albeit with a fission powered heat source... Link to comment Share on other sites More sharing options...
poida97 Member 124 Member For: 20y 11m 28d Location: Bossley Park, NSW Posted 26/10/06 06:24 AM Share Posted 26/10/06 06:24 AM I only found out through testing on my PDAs' acceleration software, bit thinking got me to the testing point.. Although Hp and Torque cross at 5252rpm. What software is that by the way?←I'd like to know too. Link to comment Share on other sites More sharing options...
F6 UTE - Track Bound EVO III - Member 3,367 Member For: 20y 2m 10d Gender: Male Location: Strapped in and holding on Posted 26/10/06 07:18 AM Share Posted 26/10/06 07:18 AM www.autoenginuity.com.auProgram called Speed Tracer comes with the logging software.The are many cheaply available Scantool programs which run on PPC 2003, WM5 and Palm handhelds. also Window$ based systems for lappies.Search google for Scantool, PDAThere are also some threads on here regarding software. Link to comment Share on other sites More sharing options...
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