Whats the % for Transmission losses?

[ENSMR2]

From Fly BHP to Wheel BHP?

I'm guessing around 15%?

N

[raptor95GTS]

From Fly BHP to Wheel BHP?

I'm guessing around 15%?

N

varies with power output and you can't measure flywheel power with the engine in the car so why bother with it

[stevecordiner]

Realistically its not a % ... its a combination of a % and a general losses figure.

I find it hard to believe an MR2 would lose much more that 10-12% given its basically a fwd layout in the back of a car.

[ENSMR2]

From Fly BHP to Wheel BHP?

I'm guessing around 15%?

N

varies with power output and you can't measure flywheel power with the engine in the car so why bother with it

Just going by the fact that most rollers give fly outputs. There must be a way of translating that figure to the wheels. I'm not bothered with it. Just doing a more research in to turbo's etc and alot of power figures are fly figures and I'm trying to figure out what that equates to at the wheels.

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Realistically its not a % ... its a combination of a % and a general losses figure.

I find it hard to believe an MR2 would lose much more that 10-12% given its basically a fwd layout in the back of a car.

Cheers Steve. So I was technically working out with too much of a loss.

I know this can get very technical. If any one can explain it in lamans terms then feel free to do so. I will try and follow along other wise.

N

[raptor95GTS]

all dynos measure TORQUE at the wheels and then calculate power at the wheels then the machine guesstimates the tranny loss

again you cannot measure power at the flywheel while the engine is strapped to a transmission and a car. It aint gonna happen

[ENSMR2]

all dynos measure TORQUE at the wheels and then calculate power at the wheels then the machine guesstimates the tranny loss

again you cannot measure power at the flywheel while the engine is strapped to a transmission and a car. It aint gonna happen

Sorry if I am not clear. I don't want to measure bhp at the fly. When I enquire about turbos most manufacturers quote fly bhp power for their turbo's all I want to do is have a guestimate at what that is at the wheels. I am not interested in fly wheel bhp at all.

From what you have said though. These RR's that give fly bhp figures could be totally out!

[raptor95GTS]

aha ensmr2, got you now I think the turbo makers quote their figures in PS not BHP which again is different arguement again

From what you have said though. These RR's that give fly bhp figures could be totally out!

yeah, some of them quite badly

[stevecordiner]

all dynos measure TORQUE at the wheels and then calculate power at the wheels then the machine guesstimates the tranny loss

again you cannot measure power at the flywheel while the engine is strapped to a transmission and a car. It aint gonna happen

Sorry if I am not clear. I don't want to measure bhp at the fly. When I enquire about turbos most manufacturers quote fly bhp power for their turbo's all I want to do is have a guestimate at what that is at the wheels. I am not interested in fly wheel bhp at all.

From what you have said though. These RR's that give fly bhp figures could be totally out!

I'd imagine turbo manufacturers will be working on a theoretical Volumetric efficiency for a X sized engine when determining the power output of the turbo's. E.g. They'll know what amount of air their turbo can flow and calculate how much fuel that should burn and therefore how much hp that shoudl generate at the fly.

They cant say what the whp figure will be, because you could put the same turbo onto a 4wd car and get totally different whp figures to a fwd car etc

[ENSMR2]

all dynos measure TORQUE at the wheels and then calculate power at the wheels then the machine guesstimates the tranny loss

again you cannot measure power at the flywheel while the engine is strapped to a transmission and a car. It aint gonna happen

I don't want to work out fly figure. I am being told fly figures by various people/ manufacturers of turbo's. I just want a rough idea of what that is at the wheels.

[ENSMR2]

all dynos measure TORQUE at the wheels and then calculate power at the wheels then the machine guesstimates the tranny loss

again you cannot measure power at the flywheel while the engine is strapped to a transmission and a car. It aint gonna happen

I don't want to work out fly figure. I am being told fly figures by various people/ manufacturers of turbo's. I just want a rough idea of what that is at the wheels.

[raptor95GTS]

heard you the first time ENSMR2 and replied

[ENSMR2]

heard you the first time ENSMR2 and replied

Sorry allan,. Its this stupid mobile thing I'm usung. For some reason my replies don't show up for some reason. I have to log out and back in about 10 time!

Now that that is out of the way: I didn't thing there was much difference between PS AND BHP. Plus I've always been told bhp whebever I have spoken to people.