N/A HP BRAG thread

[synolimit]

Originally Posted by Chuck33079

Some of those do have an effect. Your post before the one I quoted above was a bunch of unlikely and extreme examples, and not really worth much of a response.

You are correct, some of the things you mentioned do have an effect on traps to some degree. Traction/wheelhop is really to only one to be concerned with. Gas quality, temp and altitude would effect dyno numbers to the same degree as trap speeds. Your last two are asinine.

You're correct in pointing out that trap speed is not an absolute, and it can be affected by outside factors. So can dyno numbers. Dynos can be made to show you pretty much whatever number you want. The only way to get an absolutely correct hp reading would be an engine dyno in a controlled environment. Any other method has drawbacks.

Trap speed is very commonly used to calculate HP. The formula for calculating hp from trap speeds is:
hp = (mph / 215.39)3.3135 x weight (lbs)

This page has a pretty good breakdown of the math involved, if you're curious. Shamelessly stolen from a 300GT/Stealth site. Stealth 316 - Formulas for 1/4 mile ET & mph vs. hp & wgt

I just did all those for hp...304, 310, and 318 when my dyno read 280. So it can't be to accurate.

[Chuck33079]

Originally Posted by synolimit

I just did all those for hp...304, 310, and 318 when my dyno read 280. So it can't be to accurate.

What was your trap speed?

Going from the top time for a stock car in the 1/4 times thread (12.938@108.31) and the curb weight of a base sport (3232lbs), the LRT calculator for getting hp from mph and weight spits out 331 hp. The other two methods are described in the article as being less accurate. That's why I posted the specific formula for the one that was closest- hp = (mph / 215.39)3.3135 x weight (lbs)

[synolimit]

Originally Posted by chuck33079

what was your trap speed?

106.5 and that was stock air box so I guess 275hp back then.

[Chuck33079]

Originally Posted by synolimit

106.5 and that was stock air box so I guess 275hp back then.

So just a cat back?

The formula feeds you crank hp, so you would need to add back in the drivetrain losses to your numbers.. I checked it against times in the 1/4 mile thread and it was close.

[synolimit]

Originally Posted by Chuck33079

So just a cat back?

The formula feeds you crank hp, so you would need to add back in the drivetrain losses to your numbers.. I checked it against times in the 1/4 mile thread and it was close.

CBE wheels and weight.