Oh So Close....

[FlaSeaDude]

I was finally able to get my Cobra over to the tuner today to dyno and tune my Whipple setup. Oh, course, it just HAD to be the hottest freakin day of the year so far with temps in the shop around 83 - 84 degrees at the time the car was on the dyno.

So, needless to say I fell just a tad bit short of my goal of 600 RWHP and "settled" for 590 with a safe A/F ratio and 19 degrees of timing

This was with a 2.9" upper pulley and 18.76 pounds of boost. Once I've had time to get used to this setup, I'll be returning with some race gas and my 2.7" upper (and will hopefully pick a cooler day :lol1 in order to break through the 600 barrier...:rockon:

 

[homer302]

Nice numbers. What was the AF? I didn't see it listed.

 

[Jomo1994z71]

Colder day you got it...I'm sure it's a beast...congrats...

 

[FlaSeaDude]

Nice numbers. What was the AF? I didn't see it listed.

He didn't include it on the print out, but I believe it was around 11.5 - 11.75...

 

[Tom's_03SVT]

good numbers, bad news is those numbers are uncorrected. You are looking at about 575 SAE.

 

[MVD]

good numbers, bad news is those numbers are uncorrected. You are looking at about 575 SAE.

Yes they are corrected. It says right on the sheet "STD".

 

[homer302]

good numbers, bad news is those numbers are uncorrected. You are looking at about 575 SAE.

Wow. How can you tell by the sheet? It doesn't really say it is or isn't?

 

[357cstang]

Wow. How can you tell by the sheet? It doesn't really say it is or isn't?

yes. Top right corner it says STD and smoothing on 5.

Industry standard is SAE and smoothing on 5.

Strong car though, have fun with it! :rockon:

 

[homer302]

I have seen them that say that in the top and then at the bottom say correction factor 1.02 or whatever. What does that mean?

 

[357cstang]

I have seen them that say that in the top and then at the bottom say correction factor 1.02 or whatever. What does that mean?

They are different correction factors for the conditions. Dynos read numbers at the rear tires, in an uncontrolled environment. Those of us at sea level, make more power. Cold air means more power. In an effort to make the playing field level, there are correction factors which take the temperature, humidity and barometric pressure into account and standardize them.

Here's a good read:
Equations: Dyno Correction Factor and Relative Horsepower

And here's an example of the same three runs with the most common correction factors (SAE, STD and UNCORRECTED)... where Uncorrected corresponds to the actual wheel horsepower measured.

690 SAE:

Same run on STD:

Picked up a cool 22HP

Same run Uncorrected:

Finally, you can see how it's possible to pickup HP just by changing the smoothing value.

This why you have to be extremely cautious when reading numbers online. Vendors and shops can advertise great gains, and even produce results... but I just showed a gain of 41HP by manipulating the dyno program.

 

[homer302]

Great read. Thanks. I was just actually searching through threads here that talked about that. IMO it doesn't really matter as far as your own car goes if you are trying to gauge hp improvement so long as you use the same each time. Now if you are comparing 1 car to another you have to make sure they are the same.
Thanks again. Very informative.

 

[04sleeper]

Nice! :rockon:

How was your FPDC with the new set up?

 

[deec73]

Congrats dude. Hows it feel? A lot stronger than the poreted eaton?

 

[Jroc]

Yes they are corrected. It says right on the sheet "STD".

x2.

Those #'s are just as incorrect as a 1/2 wrench being incorrect, or a inch or yard being incorrect units of measurement. Ones a Standard system for measuring HP, and the others a Metric system for measuring HP.

OP the difference between STD and SAE #'s is usually 2 or 3% less for SAE#'s.

 

[blackvenom77]

Nice! :rockon:

How was your FPDC with the new set up?

+1, that was my next question.

 

[PistolWhip]

STD, SAE, who the hell cares! Great #'s and congrats on having a truely bad ass street car. Now go to the track and get the numbers that really count, the one's the dyno haters can't deny ;-)

 

[PWORLDSTANG]

Congrats, bet it pulls like hell! :rockon:

 

[TORQJNKY]

I've got DynoJet sheets that read "CF: SAE Smooting: 0". It's SAE but since it is "0", is that the same as uncorrected or does it just use current atmosphereic conditions and not take into consideration the effects of the temperature, humidity and atmospheric pressure on that day. From the read it looks like this means no correction factor applied.

 

[Posi]

Nice numbers FleaSeaDude now get that baby to the track before it really warms up down there.

 

[Posi]

They are different correction factors for the conditions. Dynos read numbers at the rear tires, in an uncontrolled environment. Those of us at sea level, make more power. Cold air means more power. In an effort to make the playing field level, there are correction factors which take the temperature, humidity and barometric pressure into account and standardize them.

Here's a good read:
Equations: Dyno Correction Factor and Relative Horsepower

And here's an example of the same three runs with the most common correction factors (SAE, STD and UNCORRECTED)... where Uncorrected corresponds to the actual wheel horsepower measured.

690 SAE:
This why you have to be extremely cautious when reading numbers online. Vendors and shops can advertise great gains, and even produce results... but I just showed a gain of 41HP by manipulating the dyno program.

I think something is amiss with your conversions. You've got about 135hp more with the standard numbers. I don't think 590hp as corrected as it could be, could ever = 700+.