Many of you have likely seen HP Calculators like this online:

http://www.dsm.org/tools/calchp.htm

About a month ago I made a quick spreadsheet based on that formula and all you need is the current weight of your car plus driver entered in the upper left corner.

The spreadsheet takes care of all the rest of the work and should offer a good "best guess" of where your HP levels are based on ET and Trap Speeds at your current weight. Factors like running out of 4th gear through the traps, better or worse than average 60' times, and increased Aero drag at higher speeds will throw things off but it's still a good rough estimate.

The general rule of thumb is every tenth gained at the 60' will reduce your ET by 2 tenths. The ~10 HP per 1 mph trap speed is also a good general guidline.

Hope it helps!

 

edit* somehow i posted this in the wrong thread. I'm a retard.

 

Thanks for sharing HiBoost! But have you also seen Jack_of_trades' Virtual Dyno Room simulator? It's also based on Excel but uses your data logs as input, and has drop-downs for different types of dynos (mustang vs dynojet) as well as weather corrections. It works really great to get a better idea of your hp/torque curve! Check it out:

https://www.evolutionm.net/forums/ec...simulator.html

Your tool is great for a total number based on 1/4 mile times though!

 

I broke down and bought Data Log Lab (only $50) and made a template to read EvoScan logs. It makes dyno graphs that calculate HP and TQ curves over RPM. Pretty accurate, too, as long as you define your Evo correctly

The nice part is that you can load a baseline log and compare that to a log you made after making changes to your setup.