BO55 VXR gets a mention on PH thread
Discussion
No mention of 4444 BY
GSI_Daz said:
470BHP? Where did that figure come from B055?
To be honest, I don't quite know where I got that figure, but I think it was a value that was banterred around in the early days & I never got it out of my head.
This figure I believe is actually nearer the 450 mark - What do YOU say, Mr Wortec?
Edited by BO55 VXR on Friday 1st September 17:53
BO55 VXR said:
GSI_Daz said:
470BHP? Where did that figure come from B055?
To be honest, I don't quite know where I got that figure, but I think it was a value that was banterred around in the early days & I never got it out of my head.
This figure I believe is actually nearer the 450 mark - What do YOU say, Mr Wortec?
Edited by BO55 VXR on Friday 1st September 17:53
our results show 448hp avarage........
wortec1 said:
As I have shown before our Rear wheel and rear hub figurs are in line with your findings BUT your calculation to Flywheel are to low.......
As you have found the gains at each stage are comparable
As you have found the gains at each stage are comparable
Paul,
First of all I want to say that this isn't anything against Wortec, I have been extremely happy with the upgrades that I have had so far.
Before I say anything, I will admit that I haven't a clue how dynos work.
The gains I have seen so far have been great, however, I would question the starting point of 400fwhp by Vauxhall. Unless you would like to question the validity of what we have seen today then Vauxhall have "robbed" us of 30 bhp to begin with. For a tuner this must be a nightmare in that you need to make up the loss before you can show any comparable results.
I am sure that Charlie, who you have used before would be interested to know where he is going wrong in calculating the FWHP.
Charlie and his dyno are reporting rear wheel HP/TQ in line with our findings......no dispute. (His is one of the more accurately run dynos)
BUT we have found that the drive train loss should be in the order of -32hp for tires and -65 for drive line losses (the T56 box is known to loose 45+ hp on its own)
SO Charlie's RWHP figures for the standard car of 295hp + 32 + 65 = 392fwhp (HSV quote 398hp)
OR Standard GTS-R RWHP of 308hp + 32 + 65 = 405fwhp (HSV quote 402hp)
The only thing wrong with Charlie's dyno is the calculation for flywheel (which is set by the machine not him.......)
It is best to stick with RWHP (or in our case RHHP)......BUT if you need to back calculate we advise the above calc......
BUT we have found that the drive train loss should be in the order of -32hp for tires and -65 for drive line losses (the T56 box is known to loose 45+ hp on its own)
SO Charlie's RWHP figures for the standard car of 295hp + 32 + 65 = 392fwhp (HSV quote 398hp)
OR Standard GTS-R RWHP of 308hp + 32 + 65 = 405fwhp (HSV quote 402hp)
The only thing wrong with Charlie's dyno is the calculation for flywheel (which is set by the machine not him.......)
It is best to stick with RWHP (or in our case RHHP)......BUT if you need to back calculate we advise the above calc......
wortec1 said:
Charlie and his dyno are reporting rear wheel HP/TQ in line with our findings......no dispute. (His is one of the more accurately run dynos)
BUT we have found that the drive train loss should be in the order of -32hp for tires and -65 for drive line losses (the T56 box is known to loose 45+ hp on its own)
SO Charlie's RWHP figures for the standard car of 295hp + 32 + 65 = 392fwhp (HSV quote 398hp)
OR Standard GTS-R RWHP of 308hp + 32 + 65 = 405fwhp (HSV quote 402hp)
The only thing wrong with Charlie's dyno is the calculation for flywheel (which is set by the machine not him.......)
It is best to stick with RWHP (or in our case RHHP)......BUT if you need to back calculate we advise the above calc......
BUT we have found that the drive train loss should be in the order of -32hp for tires and -65 for drive line losses (the T56 box is known to loose 45+ hp on its own)
SO Charlie's RWHP figures for the standard car of 295hp + 32 + 65 = 392fwhp (HSV quote 398hp)
OR Standard GTS-R RWHP of 308hp + 32 + 65 = 405fwhp (HSV quote 402hp)
The only thing wrong with Charlie's dyno is the calculation for flywheel (which is set by the machine not him.......)
It is best to stick with RWHP (or in our case RHHP)......BUT if you need to back calculate we advise the above calc......
Not wanting to open can of worms further, but, is the loss calculation non linear ?? ie percentage of power created - tyres ??
In the development of my HSV I used the same dyno everytime.What is interesting, this is a Maha dyno which prints out the wheel output and the drag output to total a FW output.
looking thro a lot of charts I find the figures run very close to Pauls ie my drag output varied between 98 to 104 whilst Paul says about 97 for Dynodynamics.
Also out of interest i used the hub dyno once and the calculation from the operater said a loss of 55-60 at the hub.Add that to hub and FW bhp came out very close to R/R dynos.Depending on conditions of the day all of the readings match up very close to each dyno,dyno dynamics included. A good dyno setup correctly, with a skilled dyno operater will show consistent results every time in my opinion.
looking thro a lot of charts I find the figures run very close to Pauls ie my drag output varied between 98 to 104 whilst Paul says about 97 for Dynodynamics.
Also out of interest i used the hub dyno once and the calculation from the operater said a loss of 55-60 at the hub.Add that to hub and FW bhp came out very close to R/R dynos.Depending on conditions of the day all of the readings match up very close to each dyno,dyno dynamics included. A good dyno setup correctly, with a skilled dyno operater will show consistent results every time in my opinion.
[quote]Not wanting to open can of worms further, but, is the loss calculation non linear ?? ie percentage of power created - tyres ??[/quote]
As you increase power you must be increasing losses as the faster you move something the more heat is generated.......
BUT this is not a simple % increase I subscribe to the add a fixed number for every x HP increase (OR more to the point every lbs ft of torque added) school of thought.
From the cars we have dynoed I feel happy to add a extra loss of 5-8hp for every 100 ft lbs over 300RWHP SO a car (HSV/Monaro etc) with 400rwhp would have an approx flywheel figure of 400+32+65+8 = 505fwhp..........
As always this must be used as a guide but from the amount of cars we have dynoed this therory fits..
As you increase power you must be increasing losses as the faster you move something the more heat is generated.......
BUT this is not a simple % increase I subscribe to the add a fixed number for every x HP increase (OR more to the point every lbs ft of torque added) school of thought.
From the cars we have dynoed I feel happy to add a extra loss of 5-8hp for every 100 ft lbs over 300RWHP SO a car (HSV/Monaro etc) with 400rwhp would have an approx flywheel figure of 400+32+65+8 = 505fwhp..........
As always this must be used as a guide but from the amount of cars we have dynoed this therory fits..
Forum | HSV & Monaro | Top of Page | What's New | My Stuff