Notices
ScoobyNet General General Subaru Discussion
Sponsored by:
Sponsored by:

Power to weight

Thread Tools
 
Search this Thread
 
Old 06 July 2008, 12:10 AM
  #1  
Mikkel
Scooby Regular
Thread Starter
 
Mikkel's Avatar
 
Join Date: Jun 2007
Location: North East
Posts: 2,281
Likes: 0
Received 0 Likes on 0 Posts
Default Power to weight

Was just looking at some power to weight figures for various Imprezas, which surprised me slightly.

The RB320 is around 207bhp per tonne, whilst the older WR1 is around 220bhp per tonne. Does that mean the WR1 will be quicker than the RB320?

Also, my spec D is around 205bhp per tonne running 360/390, so my car must be quite a bit heavier than both. Did they make the RB320 lighter? I thought it was just a PPP with frills?

On a different note - The FQ360 running the same power as my car has a quoted 260bhp per tonne, which is very impressive. Strangely though I have out accelerated an FQ360 before in my car, but surely it should be much quicker with that power to weight?

Old 06 July 2008, 10:44 AM
  #2  
tony95
Scooby Regular
 
tony95's Avatar
 
Join Date: May 2006
Posts: 207
Likes: 0
Received 0 Likes on 0 Posts
Default

other factors will come in to play,gear ratios,torque curves ,relative weight of right foot etc.
Old 06 July 2008, 11:30 AM
  #3  
stevebt
Scooby Regular
iTrader: (8)
 
stevebt's Avatar
 
Join Date: Sep 2002
Posts: 16,732
Received 33 Likes on 19 Posts
Default

I did my car on a power to weight calculator and mine came up with 358bhp per tonne
Old 06 July 2008, 11:38 AM
  #4  
rooferman
Scooby Regular
iTrader: (6)
 
rooferman's Avatar
 
Join Date: Feb 2004
Posts: 3,377
Likes: 0
Received 0 Likes on 0 Posts
Default

Mine comes out at 562 bhp per tonne on the car stats calculator........




But i lied about the bhp and the weight...............
Old 06 July 2008, 11:42 AM
  #5  
bluenose172
Scooby Regular
iTrader: (2)
 
bluenose172's Avatar
 
Join Date: Mar 2002
Location: Spec C - 12.5 @ 110(340/350)
Posts: 2,314
Likes: 0
Received 0 Likes on 0 Posts
Default

How can a 360bhp Spec D only have a P/W/R od 205?
Old 06 July 2008, 11:49 AM
  #6  
Alec
Scooby Regular
Support Scoobynet!
 
Alec's Avatar
 
Join Date: Aug 1999
Posts: 583
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Mikkel
Was just looking at some power to weight figures for various Imprezas, which surprised me slightly.

The RB320 is around 207bhp per tonne, whilst the older WR1 is around 220bhp per tonne. Does that mean the WR1 will be quicker than the RB320?

Also, my spec D is around 205bhp per tonne running 360/390, so my car must be quite a bit heavier than both. Did they make the RB320 lighter? I thought it was just a PPP with frills?

On a different note - The FQ360 running the same power as my car has a quoted 260bhp per tonne, which is very impressive. Strangely though I have out accelerated an FQ360 before in my car, but surely it should be much quicker with that power to weight?

How did you get you Bhp/tonne? Are you confusing metric and imperial ton(nes)? I think your car is around 250bhp/ton.
Old 06 July 2008, 11:53 AM
  #7  
Mikkel
Scooby Regular
Thread Starter
 
Mikkel's Avatar
 
Join Date: Jun 2007
Location: North East
Posts: 2,281
Likes: 0
Received 0 Likes on 0 Posts
Default

LOL I've probably ballsed it up then!

I was looking at the graph I got from Andy F. Its says:

360BHP@5593rpm 389LbFt@4101rpm 205BHP/ton

Edit: Spec D weight is 1495kg

Last edited by Mikkel; 06 July 2008 at 11:57 AM.

Trending Topics

Old 06 July 2008, 11:57 AM
  #8  
stevebt
Scooby Regular
iTrader: (8)
 
stevebt's Avatar
 
Join Date: Sep 2002
Posts: 16,732
Received 33 Likes on 19 Posts
Default

try using this calculaotr for your car! I think yours comes out around 260bhp per tonne


Car Stats - Calculator
Old 06 July 2008, 12:01 PM
  #9  
Mikkel
Scooby Regular
Thread Starter
 
Mikkel's Avatar
 
Join Date: Jun 2007
Location: North East
Posts: 2,281
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by stevebt
try using this calculaotr for your car! I think yours comes out around 260bhp per tonne


Car Stats - Calculator
That calculator tells me 244.67bhp/ton

I'm only 12 stone myself and I guess Andy F is not much more, so not weighing the car down that much when he took the readings
Old 06 July 2008, 12:07 PM
  #10  
Carl2
Scooby Regular
 
Carl2's Avatar
 
Join Date: Mar 2003
Location: North Yorks.
Posts: 782
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by bluenose172
How can a 360bhp Spec D only have a P/W/R od 205?
It would need to weigh around 1750kg for that.

Last edited by Carl2; 06 July 2008 at 01:28 PM.
Old 06 July 2008, 01:02 PM
  #11  
magicgreg
Scooby Regular
 
magicgreg's Avatar
 
Join Date: Jul 2006
Location: North East, Ingleby Barwick
Posts: 982
Likes: 0
Received 0 Likes on 0 Posts
Default

265bhp/tonne for me.
Old 06 July 2008, 01:05 PM
  #12  
bluenose172
Scooby Regular
iTrader: (2)
 
bluenose172's Avatar
 
Join Date: Mar 2002
Location: Spec C - 12.5 @ 110(340/350)
Posts: 2,314
Likes: 0
Received 0 Likes on 0 Posts
Default

Remember he has to take into account the fuel etc in the car too.
Old 06 July 2008, 01:29 PM
  #13  
GC8
Scooby Regular
 
GC8's Avatar
 
Join Date: Aug 2003
Location: Sheffield; Rome of the North
Posts: 17,582
Likes: 0
Received 0 Likes on 0 Posts
Default

Yes: a tank of fuel and a fat driver make a big difference (15 kilos for being fat in my case and the fuel weight can add another 35 kilos too).
Old 06 July 2008, 05:00 PM
  #14  
Mikkel
Scooby Regular
Thread Starter
 
Mikkel's Avatar
 
Join Date: Jun 2007
Location: North East
Posts: 2,281
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by magicgreg
265bhp/tonne for me.
You have the same car as me with the same mods so mine should be around the same I would have thought.

I never thought about a tank of fuel. Good point. Was 3/4 full at the time I think.
Old 07 July 2008, 11:16 AM
  #15  
magicgreg
Scooby Regular
 
magicgreg's Avatar
 
Join Date: Jul 2006
Location: North East, Ingleby Barwick
Posts: 982
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Mikkel
You have the same car as me with the same mods so mine should be around the same I would have thought.
*****, I counted the car as 1395kgs instead of the correct 1495kgs, therefore making my total 248bhp/tonne, so yes its around the same as yours.

G
Old 07 July 2008, 11:44 AM
  #16  
GazTheHat
Scooby Regular
 
GazTheHat's Avatar
 
Join Date: Aug 2005
Location: 392/361 MY04 STi
Posts: 7,638
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by GC8
Yes: a tank of fuel and a fat driver make a big difference (15 kilos for being fat in my case and the fuel weight can add another 35 kilos too).
15 kilos? You lightweight, that's only about 2-3 stone.

Just over 240bhp/tonne. Divide by 3, times by 2. Yeah! I can still do maths.
Old 07 July 2008, 02:06 PM
  #17  
jasonius
Scooby Regular
iTrader: (1)
 
jasonius's Avatar
 
Join Date: Oct 2004
Location: Half way up
Posts: 4,791
Likes: 0
Received 0 Likes on 0 Posts
Default

1350kgs (slimline WRX..) and near 350 = 260bhp/ton..
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
KAS35RSTI
Subaru
27
04 November 2021 07:12 PM
johnnybon
Subaru Parts
20
20 March 2016 09:23 PM
Mattybr5@MB Developments
Full Cars Breaking For Spares
28
28 December 2015 11:07 PM
Billet
ScoobyNet General
42
14 October 2015 10:38 PM
InTurbo
Other Marques
20
08 October 2015 08:59 PM



Quick Reply: Power to weight



All times are GMT +1. The time now is 01:09 PM.