Just wondering is it possible to calculate a car's wheel horsepower without running on dynos? Say if you are reading tru the ECU? I believe by recording the rpm together with the speed the same time you can find out the power band? But do the ECU log speed or just the speedometer, for non electronic speedo?

Butt dyno got!

No need any equipment!

It won't be accurate but you can try with those 1/4 mile softwares to calculate your engine BHP base on engine capacity and etc etc

just use back your engine's official hp (from manufacturer) and deduct 20% (for manual) or 25% (for auto), then deduct 1hp per year of usage and u'll get an estimated whp of the car. But this kind of calculation is NOT accurate of course, because there are just too many variables that can't be calculated like how is the condition of your engine and gearbox and the mileage etc. etc.

This post has been edited by stormlcc: Nov 8 2011, 04:17 PM

So if you reading tru the ECU you won't get the data required to calculate or plot the graph?

use your iphone if you have one

That sounds strangely logical.

there's an app for that

Of course there is

5 years ago ppl will think you're crazy to use your phone to measure bhp .

Nowadays can do so many things.....

i wonder how u use "iphone" to get hp ?

plug in iphone into .... CAR OBD Socket ?

or what ... ? How iphone Detect ur hp ?

by tire spinning rate ? speed rate ?

Who has done before??

Basically it is like a 1/4 mile app
You key in your engine data inside, hook your Iphone (make sure it is straight)
Then just hentam
The app will calculate your engine BHP base on how fast your 1/4 mile base on your engine capacity

used OBD2 socket, but u need to buy OBD2 wifi /Bluetooth transmitter and need to install apps like "torque" for Android and "rev" for I Phone..

the transmitter is like this.. :

I have one which looks exactly like this!

Unfortunately car running OBD1.

What about car's weight?

that's the first thing to key in. weight with driver.

that method to calculate is using any device with a gyro. which all smart phones have now. not reliable. too many variables to effect the results. to me, totally useless.

i bought dynolicious, i used it once. garbage.

Might as well just send for dyno?

Where do you connect this to, the ECU? Is it standard for most cars? What kind of data does it log other than RPM?

The weight of the car can be calculated by measuring the tyre ground area & tyre pressure.

There is a plug under the dash that this can be connected to and is linked to the ECU....