FRP power

[paulob1]

is the 153 bhp at the crank or flywheel or at the driven wheels...anyone know the answer to this...

 

[LOONEY]

a quick car lol flywheel i think as you lose power when i goes pass the gearbox

 

[Flying Scotsman]

Now i thought it was at the wheels......

 

[Sparx]

BHP specs are generally normally measured at the wheels so i would assume so.. the standard 1.7 123bhp is at the wheels so i cant see why Ford would originally measure the FRPs differently

 

[paulob1]

I cannot imagine it is at the wheels, as ford usually do it at the crank but it would be useful to know...if the new engine has 300 bhp at the flywheel I therefore can expect double the power through the box...

 

[paulob1]

interestingsparx, it would mean that the engine is producing closer to 170 or 180 bhp at the flywheel...this means my 300 bhp is not such a problem to the std box...

 

[Sparx]

yea pretty sure its at the wheels because my rolling road reading was 123 lol k:

 

[Flying Scotsman]

Paul... Put a Puma on the Rolling Road...??

Don't know what it all means lol, be he was mine from last year...

 

[Sparx]

That means you're trying to have an FRP engine but not quite quick enough hehe :-D

 

[Flying Scotsman]

Thats with just the inlet manifold on and FRP Ecu.... I have the rest on now lol.... ;p

No need to be jealous Miss 123....

 

[jacko]

as far as iv read into it all figures are measured at the wheels....BUT the run down calculates gearbox losses...so actually its a 'calculated' flywheel measurement...

its overly complicated because people SEE the car being measured at the wheels on a rolling road but that bhp figure is usually 30% less than the manufacturer quotes.....no one wants to pay for a rolling road session to see they're missing 30% of their horses so its 'calculated' back to a flywheel figure to give a more 'accurate' measurement thats comparable to when the car left the factory....

which (being geeky) makes me laugh when someone quotes a figure to within 2 or 3 bhp....like the accuracy of the individual rolling road as a measure and then the accuracy of the calculation is going to be less than 5bhp!!! er...no!

 

[markc555]

as far as iv read into it all figures are measured at the wheels....BUT the run down calculates gearbox losses...so actually its a 'calculated' flywheel measurement...

Kind of. ALL manufacturer quoted power/torque figures are "at the flywheel" but they're actual figures rather than calculated ones.

The manufacturers use an engine dynomometer, where they connect the engine minus the gearbox and indeed entire rest of the car, to directly measure the output of the engine. Of course it's impractical to remove your engine from the car and connected it to self contained electrical, cooling and exhaust systems. Therefore tuners use chassis dynomometers a.k.a Rolling Road which measure the output at the wheels then "calculate" the power at the flywheel by measuring the run down resistance of the drivetrain when disengaged (de-clutched) from the engine. There are lots of assumptions in the calculation so as jacko says this is not entirely accurate process however it is useful for comparing either several cars at the same facility on the same day/same conditions, or the same car at the same facility (ideally under the same weather conditions) before and after you make any changes or modifications.

As ever wikipedia is your friend... http://en.wikipedia.org/wiki/Dynamometer" onclick="window.open(this.href);return false;

Cheers

Mark

 

[paulob1]

as I thought, so likely we are getting only about 135to 140 ish at our wheels...assuming a 10-15% loss through the box

 

[RyanG]

Hi guys all manufacturer power claims are at the flywheel , just looked at the original frp dyno sheets and it made 154.7 bhp at the flywheel on our superflow dyno which was within 1 bhp of Ford's 2million pound dyno at the time

 

[jacko]

yep, they bed them in and test them for hours under different loads etc..all on a bench!

 

[ElDude at Allison Automotive]

I'm amazed so many people got this wrong...

The car industry NEVER tells you what the output is on the dyno bench...you always only see the misleading bulshit figure...

Unless you buy an Aston, in which case you'd get a full report printout of the engine inside the car you've bought Which is why i also like Genesis car amps, which do exactly the same, then there's no bully.. :lol:

Don't know if porsche do a similar service, but i expect they would on high end models.. :idea:

 

[Flying Scotsman]

I'm amazed so many people got this wrong...

Not everyone is a mechanic... some just like the Car..

 

[jacko]

el dood isn't a mechanic (neither am i though; we're both enthusiasts)

and i think most people who are aware that a car has a performance figure know its not 'there' car thats being quoted

and if were getting stupidly technical even the aston martin figures are wrong because it takes about 5000 miles to free the engine to max power....no one, no matter how geeky, is going to buy an aston thats been 'run in to max power' and has 5000 miles on the clock....like the gt-r comes with a bhp figure as an estimate; because every engine is handmade. well...every engine is different but when were talking 2% difference on a 155bhp (2.5bhp) it isnt quite the same as 2% of 500bhp (10bhp)

and like anything else the manufacturer is going to quote the best figure it can (unless its swindling the insurance industry as ford did with the fiesta zetec-s).....that best figure IS inside a laboratory on a bench under controlled and repeatable conditions not out on a drive in the country or in a garage with a rolling road at different altitudes, atmospheric pressures, temperatures, humidities, air flow, particulates.....etc....etc....etc

 

[Flying Scotsman]

well if the best is on a bench, then lets all start pulling our engines out because you say its best... or we can do what everyone else does and just us a rolling road.... people make buisnesses and livings out of it you know... :thumbs:

and 'freeing and engine to max power' ... give me a car at 10 miles on the clock and i'll red line it to max power... or is it at 5000 miles that a magical trap door opens in the pistons and ut pops some more horses... lol

And nobody said you or el dude was a mechanic... and everyone here is an entusiast of some sort... just because we dont stick our heads into numbers all night doesnt make us any less enthusiastic than yourself... or el dude.

 

[XIIVVX]

Don't know if porsche do a similar service, but i expect they would on high end models

Can't think why.

We know how much power we have - Plenty