Had a spontanious opportunity to Dyno my new Boss today so took advantage of it. Car is factory stock with K&N Air Filter as only mod.
It's just broken it with about 1200 miles on it.
Max Power was 367.22
Max Torque was 323.45
I'm wondering if that was a good or bad run?
Anybody know?
Run conditions were 94.81 F
27.31 Hg.
Humidity 15%,
SAE 1.12
Run was in 4th gear to 7200 RPM

Does anybody know how to convert that back to engine horsepower, ..... I'd be interested in knowing how that number compare to the 444 hp Ford gives the engine.
This was my first ever dyno run ever, and was just a tad intimidating, as everything that was happening was new to me.
Cheers,
Jouster

 

444 at the flywheel with about a 15% loss is 377, with 20% its 356.

 

Slap a CAI and a tune and you'll be looking at 400 to the wheels much like the GT's are pushing.

 

The run should have been done in 5th gear, as it is 1:1 with the 6 speed.

 

EVERY SINGLE dyno reads differently. And there can be as much as 30% OR MORE difference between manufacturers. Contrary to popular belief, dyno's aren't meant for peak horsepower 'shoot-outs'. They're uses are many, but in the realm of measuring power, you use them to chart progress. In your case, you just base-lined your car. Now if you go out and do another mod-say full exaust... You run it after you install it ON THE SAME DYNO! The difference between the baseline and after your mod(s)-the 'gain' is the number concern yourself with.
You also use them to read the air-fuel mixture in order to build a map. In this case, you strap the thing down, run it up and down, locking it in at various rpm's, and mapping the air-fuel at those rpm's at various throttle positions. Obviously WFO is one area you map it, and concern yourself with, but in the Real World PEAK numbers ARE NOT the most important ones. You can liken it to two cars running the 1/4, with the loser actually having the faster measured speed.
Again...the MOST important thing to remember here is, keep your baseline(most of the time the dyno operator will also store it as well) read-out, and after you do your next mod, have it ran on THE SAME EXACT DYNO. The gain(and hopefully not a loss) is the ONLY number to concern yourself with.

 

Kinda low, I thought the Boss's dyno stock around 400?

 

Actually fairly typical. A few have run higher but most of the numbers I've seen are in and around here.

 

FWIW ive noticed dynoing my car that in 5th the car is **** near the speed limiter of 155. if you change the red line with a tune, i think you may have to dyno in 4th or the speed limiter will kick in. my car was at 154 and some change according to the dyno with the factory red line and a few mods in 5th gear. was it a dyno jet or mustang dyno?

 

Don't know the dyno details, but I'll come clean and say on my first run ever, I accidentally put it in 6th instead of 4th. Not much over 300 Rear wheel HP on that run, but I swear to God it was 'the fastest run' ever made on that dyno!
BTW, it topped out at 6000RPM in 6th.
Cheers,
Jouster

 

I didn't know 5th gear was 1:1.
I was told 4th gear was,.... so I went with it.
I think it would have done better in 5th, and better if it had been a cooler than 94F and 15% Humidity.
Thanks to all for their input.
Cheers,
Jouster

Sorry for the double post guys,....

 

4th gear is 1:1 for the 05-10's (and previous stangs) new stang 5th gear is 1:1 but you will hit the stock limiter before you redline.

 

Had you been in 5th gear, your numbers would have read a bit higher.

 

You might have gotten a few more horsepower if you had taken it all the way to redline -- 7,500 rather than 7,200.

 

....... maybe your right, but the HP curve was already flattening out well before 7200 rpm. That was something that surprised me, because I was under the impression that it was at the very top end where the extra horses above the 412 hp, kicked in the Boss.
However, the dyno owner warned me not to hit the rev limiter, as it can get the car 'surging' on the dyno. I didn't want to go into orbit, especially with a lot of people standing around.... so for once I listened to the man!
Cheers,
Jouster

 

Why?

Power was lower because you only ran it to 6k

Not necessarily true.

 

For a comparison..... 1st time on o dyne my Boss was in 4th gear as well and had a run of 366 RWHP. When I pointed out the error that 5th gear was the 1:1 ratio it was decided to retry. Final number in 5th gear was 369. It was Florida... hot and humid so I was told these numbers were not bad. I had expected higher based on some numbers other members had posted in different threads on different forums when the Boss first started to appear on the streets. Overall though it seems to be right with the average others are seeing in these same ambient conditions.

EDIT: my RWTQ was 341

 

Well David, looks like we pulled almost the same dyno numbers, so it's all good!
I have no burning need for much more HP than that, .... although I do look forward to trying the Trac Key when it comes out.
I uploaded a Bremspeed program into my wifes 2011 5.0 C/S convertible last fall, and was shocked at how much more jump the automatic had on take off and shifting gears. So much so, I removed it immediately because it would hop over half a lane, just shifting.
What I'm begining to enjoy these days with the Boss, is how fast and tight the car corners and shows no intention of breaking loose.
Too much fun! ........ BTW, we have the same color Boss.
Cheers,
Jouster

 

Using a 15% loss, wheel HP divided by .85 = engine HP.

 

A good rule of thumb.
In my case the heat and humidity increased the loss and put the 0.85 factor closer to 0.825.
So 367 rear wheel HP multiplied by 0.825 = 444.8 engine HP, ... or so!
Cheers,
Jouster

 

That would be divided by...