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And whats the difference from BHP to just normal HP.

BHP refers to an engines power with nothing else dragging it down (no mufflers/gearbox/diff/aux components etc). So in reality it is the power the engine makes before it is put into the car hooked up onto an engine dyno in a workshop.

HP is just the overall unit of measurement and can refer to anything eg. HP @ the wheels.

Lets say your car makes 330kw at all wheels whats that in BHP & HP.

330kw@wheels is around 442hp@wheels.

To convert that to BHP is more of a guessing game and gets brought up on the forums quite a lot. Most methods people say are completely wrong (percentage, fixed amount etc). The only way to truely convert it is to know the BHP of the engine, then to know the HP@wheels of that exact same engine. Work out the loss of power and use that as your "x". Then when you have more power, so in your case 442hp@wheels, add the "x" and this will be your rough lowest amount of BHP. It will naturally be a bit more than this as there will be more loss, but this can't be worked out accurately enough for the sake of these discussions. There are a lot of factors that come into play and it gets quite technical.

So just quickly as an example (I have done this one a few times in the past).

Car makes 400BHP when new.

Same car put onto a dyno makes 350HP@wheels.

Loss of 50HP.

Three years later the car has been modified with an exhaust, tune and more boost and now makes 500HP@wheels.

Add back original loss of 50HP.

The rough lowest amount of BHP is 550BHP.

However in reality it will obviously be slightly more than this as more loss has occured.

When a car is advertised brand new do they ever tell you the AWKW or is it engine KW?

Only ever BHP.

Hope that clears all that up for you.

Only ever BHP.

Hope that clears all that up for you.

Execpt sometimes those figures a kinda fudged lol.

eg the new supercharged V8 falcons, are rated at 335kws at the flywheel, but they reel off 340rwkws dead standard lol

so it would make 335kws somewhere in the rev range.

Yeah they bullshit the figures sometimes. But they are ment to be rated as BHP.

Really? They make that much at the wheels standard? Wow.

Yeah...it does make sense though, I mean the standard NA 5L makes 307kw, then they strap an Harrop HTV1900 blower on it an only make a few killerwasps more...yeah right lol

They are bloody pathetic at getting that power to the ground then !!! Obviously need some 19 x 10 on the back and 275/35/19s.

Btw each car is different. I use [(Engine Kw)-15]x 0.85 = rwkw..................

...............but then again...I'm a d!ckhead. :3some:

Edited by simpletool

They are bloody pathetic at getting that power to the ground then !!! Obviously need some 19 x 10 on the back and 275/35/19s.

Btw each car is different. I use [(Engine Kw)-15]x 0.85 = rwkw..................

...............but then again...I'm a d!ckhead. :3some:

its easier to just do HP x 0.746 (or 0.75) = KW

or the other way KW x 1.36 = HP

Execpt sometimes those figures a kinda fudged lol.

eg the new supercharged V8 falcons, are rated at 335kws at the flywheel, but they reel off 340rwkws dead standard lol

so it would make 335kws somewhere in the rev range.

Are you sure 340rwkw dead standard?? I read about one that had the boost turned up and tuned making that power.

I know they are bloody impressive but I dont think 340rwkw dead standard.

Are you sure 340rwkw dead standard?? I read about one that had the boost turned up and tuned making that power.

I know they are bloody impressive but I dont think 340rwkw dead standard.

seen a few dyno runs now...one even ran 353rwkws but is a rather happy dyno

with a tune, good exhasut and WMI they will do 400rwkws.

Cant wait for the intercooled ones, so they can throw some real boost into them

so even if we say they are all happy dynos, how many are happy by even 40kws?

edit - they run 114mph through the traps on street tyres, they weigh 1820kgs + driver

seen a few dyno runs now...one even ran 353rwkws but is a rather happy dynowith a tune, good exhasut and WMI they will do 400rwkws.Cant wait for the intercooled ones, so they can throw some real boost into them

Gearbox says no.

353rwkw so around 430kw at the engine. That's 240kw/tonne or 116 mph trap speed (minimum).

I don't think they make that power stock the gs rated 315 from factory pulls about 260rwkw then after tune without any other modifications 380rwkw. I'd say gt would be about 280rwkw at most.

Take note that once tuned the gs/gt are identical power.

exhaust, pulley, water injection

Has anyone seen what the dyno readout looks like after 2-3 runs though?<br>Massive heatsoak in the 'heat diffuser', then the PCM shuts down the maximum<div>throttle position to around 30%.....<br>One good run down the track, then an hour and a half waiting for the <br>temps to drop to normal hahaha.

</div>

Edited by TurboMick

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