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Power / Weight ratios

Posted: Sun Feb 27, 2011 5:25 pm
by Taz
I know that probably no one cares but hey, i'm bored and got a forum i can post on.

For all those that need their daily fun fact here is one on the FTO.
Not sure about the others but the GPvR has a power to weight of 0.08 stock.
That may not seem like much but compare it to something like a ferrari testarossa, which has a p/w of 0.104 stock, u start to realise that it has some balls.
Dyno'd my FTO the other day and got a result of 252HP @ 7500, and with a kerb weight of 1120, mine sets in at 0.102
Considering mine is non-turbo and many of you out there have turbo'd, and replaced other critical engine parts to add more HP, most of u probably dont know your car is well...amazing in that department.
Other supercars that have awesome p/w ratios too are:
* Chrysler ME Four-Twelve - .295 hp/lb
* McLaren F1 - .251 hp/lb
* Bugatti 16/4 Veyron - .230 hp/lb
* Ferrari Enzo - .219 hp/lb
* 1965 Ford GT40 Mk1 - .213 hp/lb
* Ferrari Koenig 360 Modena - .174 hp/lb
* Lamborghini Countach - .139 hp/lb
* Dodge Viper RT/10 - .131 hp/lb
* Chevrolet Corvette Z06 - .123 hp/lb
* Porsche 911 Turbo - .119 hp/lb
* Ford Mustang Cobra R - .107 hp/lb
* Ferrari Testarossa - .104 hp/lb
Am curious to see that if someone did a 4G63T swapout, stripped the car down as much as possible and modded the f*** out of it for track then i wonder where on that table it would stand...
Im so bored right now :cry:

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 5:26 pm
by Taz
Forgot to mention, those ratios are HP/Pound
I say cause someone is bound to point it out at some stage :lol:

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 5:30 pm
by mr_andersen
Taz wrote:Dyno'd my FTO the other day and got a result of 252HP @ 7500
What engine/mods have you got?

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 5:39 pm
by pete_gpx
mr_andersen wrote:
Taz wrote:Dyno'd my FTO the other day and got a result of 252HP @ 7500
What engine/mods have you got?
I'm guessing he means 152hp and mistyped it. 252 on an N/A 6A12 would be an expensive feat to achieve.

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 6:01 pm
by Taz
a stock GPvR/GPX comes stock @ 200BHP?
unless of course this page here is wrong?
http://japseye.co.uk/FTO.htm

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 6:04 pm
by aza013
:? my car only has aprox 189hp ATWs

the 200BHP is at the flywheel not the wheels.

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 6:13 pm
by Taz
and my 252 is what i would have at my flywheel assuming your typical loss to the wheels from it.
on the assumption that the ones i am going off are to the flywheel, then i would have to convert mine to it aswell to get a valid reading?

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 6:29 pm
by pete_gpx
Taz wrote:and my 252 is what i would have at my flywheel assuming your typical loss to the wheels from it.
on the assumption that the ones i am going off are to the flywheel, then i would have to convert mine to it aswell to get a valid reading?
Generally, power is judged at the wheels, rather then at the flywheel or 'engine'. That being said, I'd be skeptical of a 52hp gain, even at the flywheel, over factory specifications on a 11+ year old FTO without the kind of work that people like Aza have had done...

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 7:08 pm
by Taz
Once again, assuming that the P/W ratios are at the engine, (which i have stated several times) like most manufacturers state this argument of mine is somewhat valid.
I dont know what kind of work Asa has had done, but ive put in a full HKS SPF induction system, HKS Super Drager exhaust, and many other small things to slightly boost HP such as iridium plugs, fully synthetic fluids etc.
Im going to have to ask why factory specifications are no longer 'valid' as such as you state (unless i am reading the statement wrong) on a very well maintained low km FTO
Im also going to have to ask what 'kind of work' aza has done and what he is putting out for a 52hp gain to be 'very skeptical'

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 7:28 pm
by pete_gpx
Taz wrote:Once again, assuming that the P/W ratios are at the engine, (which i have stated several times) like most manufacturers state this argument of mine is somewhat valid.
I dont know what kind of work Asa has had done, but ive put in a full HKS SPF induction system, HKS Super Drager exhaust, and many other small things to slightly boost HP such as iridium plugs, fully synthetic fluids etc.
Im going to have to ask why factory specifications are no longer 'valid' as such as you state (unless i am reading the statement wrong) on a very well maintained low km FTO
Im also going to have to ask what 'kind of work' aza has done and what he is putting out for a 52hp gain to be 'very skeptical'
A cat-back exhaust, pod filter and cold air intake are not going to net you any significant gains on their own, let alone 50+hp. Iridium plugs, synthetic oils, upgraded ignition leads etc.? Maybe 2hp, all combined.

Engines become less efficient, therefore losing power, the older they are and the more kilometers they rack up. Cam lobes and pistons are ever so slowly being worn away every time you drive your car. Even with stringent maintenance being performed throughout the cars life, I could guarantee your engine, if stock, would no longer be producing the power it was released with from factory (which is technically 197hp, not 200). With a bit of forum stalking, it seems your car is 13 years old, with around 100 000km on it. Hardly brand new.

Aza, if I recall correctly, has such modifications as a full exhaust, intake, head porting and more. He also has an aftermarket ECU, which will actually enable his engine to take full advantage of the various breathing upgrades he has.

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 7:46 pm
by aza013
Well to start with if I can recall right the FTO has aprox 157hp atws stock.
I am running aprox 189hp. That's not a 52hp gain :?

As for what work I have done well:- port and polish and port match, compression bumped up a little bit, cai uas kit, high flow cat and muffler, mivec controller, hailtech piggy back ecu and tune. That's just of the top of my head.

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 8:13 pm
by Taz
Huh, are you sure youre only running 189?
i mean you probably are but that really doesnt sound like much for what you have done, and i havent even gone as far as a tune yet so youd definetly be a bit more than me?
the hi flow cat back and intake should alone add 25+ over stock let alone a tune, piggyback etc so either mine or your dyno is not accurate or something.
something somewhere isnt right, and its probably me.
but still, it worries me that all of that only gives you 32 HP gain :(
i highly doubt that because i have HKS branded gear that it would bump me up 20 HP above you, but out of curiosity, what have you chucked in your car?

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 8:15 pm
by Taz
makes me REALLY not want to spend all that money on an ECU upgrade and a controller if its gonna give me jack all performance till i supercharge mine.

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 8:16 pm
by Taz
Makes me REALLY not want to spend all that money on an ECU upgrade/controller if its gonna give me jack all performance till i supercharge it

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 8:16 pm
by Taz
(net cut for a second thus the spammin, didnt show when i refreshed it =/)

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 8:23 pm
by pete_gpx
Taz wrote:Huh, are you sure youre only running 189?
i mean you probably are but that really doesnt sound like much for what you have done, and i havent even gone as far as a tune yet so youd definetly be a bit more than me?
the hi flow cat back and intake should alone add 25+ over stock let alone a tune, piggyback etc so either mine or your dyno is not accurate or something.
something somewhere isnt right, and its probably me.
but still, it worries me that all of that only gives you 32 HP gain :(
i highly doubt that because i have HKS branded gear that it would bump me up 20 HP above you, but out of curiosity, what have you chucked in your car?
Aza is talking horse power at the wheels, which is the generally accepted way of assessing a modified cars output. You, however, are using flywheel horsepower, or power 'at the engine' to rate your vehicles performance. When the energy from the engine is transferred through the gear box and differential, then to the wheels, power is lost.

A manual front wheel drive loses around 20% of its power through drive-train losses. Effectively, Aza would actually have around 227 horse power at the flywheel. Therefore, you do not have 252hp with the modifications you're running.

A high flow cat and cold air intake is not going to give you 25 horsepower. You're living in fantasy land.

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 8:27 pm
by Shane001
^^ this. I'd love to see you're dyno sheet ;)

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 8:29 pm
by aza013
At the end of the day numbers are nothing :? It's how fast it is around a track and the strip that makes a car.

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 8:31 pm
by Shane001
^^ very true.

Remember, a lot of dynos are poorly calibrated, and many are deliberatly wrong to give the customer a high number so they look good :o

Re: Power / Weight ratios

Posted: Sun Feb 27, 2011 8:38 pm
by pete_gpx
Very true on the dyno comments.

My manager from work has a manual FG F6 Typhoon ute, rated at 315kw from factory. Shortly after buying it, he went to have a power run on a dyno to see what it would pull before any modifications. The printout from the run, which he has showed me, displayed a result of 297kw at the wheels, which is practically impossible given that the car was brand new and completely standard.