Ok ...how do you find the difference b/t crank hp and whp
 

is there like a math problem or something that will tell you how much crank hp you have. Can you take your whp numbers and convert them? i was just wondering this during work lol.

depends on the car. For the rx-8, it's 11 - 15% less for whp vs crank.

either get dyno results from the same engine on an engine dyno and chassis dyno and compare.... or do a whole lot of research, get a Mechanical Engineering degree, and do a whole lot of calculating

...or just make use of a general percentage assumption

I'm guessing the losses (as a percentage) reduce significantly as you increase the hp by boosting ?

You can test it yourself - enter quarter mile times and speeds, weight etc. and it will give you a rough estimate.

http://www.dragtimes.com/horsepower-...calculator.php

S

The problem is few of us are taking our engines out and doing an engine dyno then doing a regular dyno to compare.

We estimate based on the numbers we do have. I guess it matters if you think Mazda is accurate with the 232 hp claim.