dynoed my cobra.

ZOSO

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04 bone stock.
400rwhp%20graph.jpg
[/IMG]


lemme know what you think :shrug:
 

mwaull

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uuuuuuuuuuuuuuuhhhhhhh . . . can you say "FREAK"!!! Those are ridiculous #s if it is stock down to the filter!

:eek:
 

03yllwguy

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Uh, is it me or is your a/f super lean? I thought from the factory our cars are pig rich... guess not.
 

ZOSO

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bone stock down to the filter. only thing i've done is change the oil.
It was a tailpipe sniffer. I too thought they were rich and I'm sure it is if you get a reading from a wideband o2 up front.
The first run was 392hp 376tq
the second was 389hp 378tq
the last run was 400.
 

lifter213

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That definately doesnt look like a stock dyno. Almost looks like it would with an intake and a tune via chip or predator. That a/f is damn flat for a stock tune, and rather lean IMO. Stock tune should dive down and get way rich in the upper rpm's. All the stock dyno's i've seen have looked like mine or pretty close...

Cobra%20dyno%201-25.jpg
 

ZOSO

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On the other runs the a/f did dive rich after 6200rpm. I shut down right before 6200.

It is 100% stock. No intake no chip no nothing. just regular 5w20 oil.

It has 2300miles on it. I heard about the loop mode on the computer which is supposed to run pig rich untill 2000mi then lean itself out.
 

SICKBOY

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tailpipe sniffers typically dictate a decent amount leaner as it is measure after the cat....I would be hard pressed to say a stock tune would be that lean measured at the "bung" ...as all I have seen are pig rich...I would never go by the sniffer as a actual "real" reading...IMO
 

ZOSO

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Well after looking at some other cobra dynos on that dyno the a/f ratio in dead nuts. Looks lean cause the tailpipe sniffer. Oh-well 400hp for a bone stock 04 is fine with me. I thought it would only be around 370. :p
 

o3SnakeBite

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Holy crap your car's running lean... Are you sure you dont have maybe a predator tune or something? Did you buy the car used? I have never seen a stock cobra dyno 400rwhp stock! Thats about 470fly wheel power... Over the rated 390, thats insane
 

Chucko

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Take a closer look at the dyno chart. He's obviously at high altitude based upon his barometric pressure (and his sig shows Colorado) and the SAE correction factor is 1.21 (adding 21% to the actual numbers that he pulled).

My experience is that it gets real tough to try to compare a dyno run at sea level with one done at high altitude. The CF when that high is only a rough approximation - the granularity is just too high.
 

fast1

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Sorry man, but I can't see your Cobra being 30rwhp more than everbody else is.
 

mlambert

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Noone here looked at the correction factor besides chucko yet everyone cried about how much power it "made".

Proper CF for altitude ALWAYS depends on manifold pressure (and obviously ambient air temp), it's nowhere near accurate if you just use a 1.xx for whatever lb's of boost you're pushing.

The CF he used is for a NA car, at 10psi or so he should be using around 1.10, so figure his numbers are 10-12% inflated (or more, I have a formula to figure it out but the 1.10 is just a rough guess).
 

CobraBob

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Something is definitely wrong with the A/F. Your running dangerously lean is the reason you made 400 to the rear wheels. That A/F doesn't look anywhere near stock to me. Or.....that dyno is messed up. Have him check his air filter.
 

sambandit

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Why cant we just accept this car as a phreak instead of blaming correction factors. I also live in CO and am sick of people telling me this crap about how a SC has some sort of advantage at high altitude, it just isnt so. I picked up over 8 tenths and 10 mph going from here to sea level. That is alot for a NA car let alone a SCed one. This is an accurate dyno as I have dynoed there before and so have many other people who have numbers right in line with what they should be.

On a side note, the A/F is strange though. It's almost like the car has a tune in it already and that would contribute to the higher numbers. I have never seen a car in stock form that lean. I assume the A/F curve for all 3 pulls was similar?
 

mlambert

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sambandit said:
Why cant we just accept this car as a phreak instead of blaming correction factors.


Did you even read my post? The CF used at that dyno is for a naturally aspirated vehicle, not one with any type of forced induction. I'm not making that up and his car is NOT a freak.
 

sambandit

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mlambert said:
Did you even read my post? The CF used at that dyno is for a naturally aspirated vehicle, not one with any type of forced induction. I'm not making that up and his car is NOT a freak.
Did you listen to me? Yes, I read your post. My point is, no matter what you would like to believe, Correction factors for NA and SC cars should be the same. Turbo is a different story however.

BTW, why do you think the CF was for a NA car. What's the difference?
 
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mlambert

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sambandit said:
Did you listen to me? Yes, I read your post. My point is, no matter what you would like to believe, Correction factors for NA and SC cars should be the same. Turbo is a different story however.

BTW, why do you think the CF was for a NA car. What's the difference?


Well the only thing I can tell you is that you're completely wrong. Forced induction is forced induction is forced induction when it comes to manifold pressure.

The reason I state that 1.21 is used for NA cars is that is what dyno shops use for NA cars in high elevation (normally its anything from 1.22 to 1.28, way too high and results in inflated numbers and :bs: from newbies). They adjust for ambient temperature but not manifold pressure.

A good rule of thumb floating around the 'net is 1.087 times the raw numbers for forced induction (if boost pressure is around 1 bar) and 1.175 for NA. It's still all synthetic though and the raw numbers are the real numbers you should be using as a baseline.

If you're concerned about what kinda power your vehicle would make at sea level, go to a track at sea level and find out.
 

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