BHP

1. shaxo79 Newbie Joined: Dec 2005 oldham United Kingdom (England) Posts: 3

   #1 5th December 2005, 03:23

   Some one please tell me whats the difference between at the wheels and at the Fly when gettin BHP estimates, ie vts 120bhp is that wheels or fly and what do these mean? im a bit slowwwwwww. lol cheers
2. shaxo79 Newbie Joined: Dec 2005 oldham United Kingdom (England) Posts: 3

   #2 5th December 2005, 03:35

   anybody?
3. mark_saxo Frequent Poster Joined: May 2005 Posts: 839

   #3 5th December 2005, 03:41

   at the fly is basically the power your engine puts out. the power at the wheels is the power after it goes through your gearbox and transferred to moving power
4. Scottp Administrator Joined: Dec 2002 Glasgow United Kingdom (Scotland) Posts: 26097 Chelski Traktor

   #4 5th December 2005, 04:13

   a99% of manufacturers quote at the fly because the figure is larger. It means not much as said above its the power at the wheels that drives the car. Citroen quote at the fly wheel figures so 120bhp is at the fly on a vts.
   
   on a rolling road the poiwer at the fly can only be guessed, the fly wheel figues can only be measured accurately from there, i.e. engine out
5. DevilDamo Saxperience Addict Joined: Sep 2003 Posts: 13761

   #5 5th December 2005, 17:21

   Standard(ish) power output for a VTS is...
   
   120bhp (Fly)
   100bhp (Wheels)
6. cammedvtr Established Member Joined: Mar 2005 hull United Kingdom (England) Posts: 1518 saxo vtr

   #6 7th December 2005, 02:08

   they say a rough calculation is to take 23% of the fly fig to get the wheel fig on a shitreon. Scott the rolling road i use gives the fig at the fly because im sure my vtr isnt 133bhp at the wheel.....
7. Scottp Administrator Joined: Dec 2002 Glasgow United Kingdom (Scotland) Posts: 26097 Chelski Traktor

   #7 7th December 2005, 02:15

   yes it gives a fly wheel figure using a preset calculation from the power at the wheels. You cannot measure the fly wheel fugure at the wheels its just impossible.
8. cammedvtr Established Member Joined: Mar 2005 hull United Kingdom (England) Posts: 1518 saxo vtr

   #8 7th December 2005, 02:20

   ok mate...
9. unplugged Infrequent Poster Joined: Nov 2004 stoke-on-trent United Kingdom (England) Posts: 196

   #9 7th December 2005, 02:38

   
   
   i got one of them g tech pro meters, which i know cant be as accurate as measuring on a dino but i tried to measure my horsepower on my vts. So i redlined second gear only because aerodynamics would slow me down after that and it says mine is 95bhp
10. Scottp Administrator Joined: Dec 2002 Glasgow United Kingdom (Scotland) Posts: 26097 Chelski Traktor

    #10 7th December 2005, 03:19

    no point in recording in second gear as it wont give a true reading, 4th is the the closet to 1:1 ratios to give more accurate reading
11. unplugged Infrequent Poster Joined: Nov 2004 stoke-on-trent United Kingdom (England) Posts: 196

    #11 7th December 2005, 04:19

    it does recommend to redline it all the way through each gear to gain a more accurate reading but theres no where i can go and do 127 mph and at that speed scott theres more wind resistance so surely that would reduce the bhp reading so thats why i tried it just in 1st and second gear but going by that 20% off 120 = 24 - that off the 120 you get 96 bhp