Such as the one at DSM.org? I'm trying to get a handle on my power without dynoing it. I assume it's somewhat accurate right? Thanks

 

How accurate are hp calculators???
Umm NOT VERY

 

Usually, not very good. That ET method is crap - BUT, MPH wise it rates your car as 235HP. That's pretty damn accurate if you ask me. Do you have a single cat? Your rated at 230, and add the minimal mods...

I've always thought my car had around 270HP (99-100MPH traps), but according to that calculator I have 275HP

 

Only the MPH method comes close, ET wise has too many variables to be accurate. Not even dynos are as accurate as can be. These HP calculators help you figure out how your car is responding to mod, but not to tell your friends "Hey I have 300 rwhp ... this calculator says so".

 

They are about 1% accurate, No formula can include all of the variables.

I guess the way I see it is go to the dyno or take it to the track.

 

WOW....if the MPH method is pretty close. Then my 305 in my El Camino has exactly 100hp....LOL ran 19.5 @ 71mph....and is 3550lbs......Wow that sucks.

 

Here is another: http://sethirdgen.org/hpcalc.htm

They are not very accurate. They all use a common formula, but it cannot account for many of the variables that exist in drag racing. All the calculators said I should have 307 RWHP, but at the dyno, I only put down 271. HUGE DIFFERENCE!!!

 

HP calculators are missing a very important peice of info Weather. Using a et predictor at the track it said my car was making 420hp to the ground. With the moroso hp slide ruler using the same times it said that it makes 385. If the car ran those times at sea level the slide ruler would be accurate.

Jason