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Stock 2009 KR RWHP


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We had wanted to dyno the KR at Carlisle last year but evidently there was not room for it. This year they were back and my wife Donna gave me the dyno pulls for Father's day. We were able to get in fairly early in the morning although it was still quite warm and muggy. For our KR, on this particular day, we were able to get 490 496 RWHP and 469 ft/lb torque. The dyno operator told us that on a cooler and less muggy day, we might have pulled slightly higher than 500. Since there have been several discussions on stock KR RWHP, I thought I would post so that there would be at least one base line number to work with.

KR Dyno June 8 2013.pdf

KR Dyno June 8 2013.pdf

Edited by SGT0767
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The dyno was a Dynojet 248 so I don't know if its readings are generally higher or lower than others. When I calculated back to flywheel HP, using 10% loss yielded 544 HP and using the normal 15% yielded about 576 HP. I have read where normal loss is between 10% and 15% but, without any other stock KR numbers to work with, its pretty hard to determine whether the numbers where underrated or the dyno was just being generous.

 

Maybe someone else has some base numbers that they can post that would help make things clearer.

Edited by SGT0767
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yeah, i'm no expert, but i think 10% is still too low. i thought with a manual transmission, loss would be in the neighborhood of 13-15% (auto would be even higher, like maybe 18%). perhaps with an aluminum or carbon fiber drive shaft and an aluminum flywheel you could get it close to 11-12%?, i don't know for sure. maybe someone with actual experience can chime in. still good numbers, nonetheless.

Edited by 2007tungstenGT500
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Thanks. I was pleasantly surprised by the number. Using the 15% loss, I was expecting closer to 460. Of course, I still need to make few improvements since, after installing Tasca's Stage II upgrade, Donna's GT500 is putting out 528 RWHP. Can't have the KR being overshadowed you know. :lol:

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With the GT500 drive train loss is closer to 15%.

 

Saw your KR dyno'd at Carlilse this weekend at the Shelby Event. Dynoed at 496 rwhp according to the sheet.

 

The KR clearly seems to put out 575hp to 590 hp at the crank depending on conditions.

 

No doubt Shelby under rated the power on these cars likely for insurance reasons at the time.

 

 

Evan

Edited by REAL ONE
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Hi Evan,

 

You are correct. I had pulled the sheet to scan it and add it to the post when I noticed that the number should have been 496. Guess the memory and eye sight aren't what they used to be. My scanner isn't working so I will need to scan it at work and add to the post later.

 

Mike

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  • 1 year later...

they were UNDERRATED....... by 50-75 hp, i have seen them over 500rwhp stock... on more than 1

 

The idea that these GT500KRs are somehow underrated from a peak horsepower perspective has got to be a complete myth. I would chalk it up to dynamometer calibration, which I'm almost certain is different than what Ford uses. There's nothing particularly special about the cold-air kit and tune that comes on these cars.

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The idea that these GT500KRs are somehow underrated from a peak horsepower perspective has got to be a complete myth. I would chalk it up to dynamometer calibration, which I'm almost certain is different than what Ford uses. There's nothing particularly special about the cold-air kit and tune that comes on these cars.

Perhaps Ford's claimed 40 hp gain from it's cold air/tune is conservative. It wouldn't be the first time they did that. Remember the 03/04 Cobras. My KR has dynoed at 500 to the wheels too. There are others that have done the same. I've personally witnessed it.

Edited by Captain Beyond
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Perhaps Ford's claimed 40 hp gain from it's cold air/tune is conservative. It wouldn't be the first time they did that. Remember the 03/04 Cobras. My KR has dynoed at 500 to the wheels too. There are others that have done the same. I've personally witnessed it.

Thanks Captain.

 

AK.

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i dont disagree. but i think the truth is in HOW its being measured. stands to reason that a dyno for service would want to err on the side of higher numbers. it makes good business sense.

Perhaps, but I've seen 11-12 GT500s dyno slightly less than KRs on the same dyno same day. Those are rated @ 550hp.

Edited by Captain Beyond
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Too many variables to know for sure, but the Ford tune in the 11-12 GT500 is not the same as the Ford Racing tune in the 08-09 GT500KR so that's plausible. Anyway, it's common knowledge the Ford Racing tunes are slightly more aggressive than Ford factory tunes (although Ford Racing tunes are still relatively conservative). Factor in aftermarket dyno calibration settings to that and it's a pretty good explanation.

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Too many variables to know for sure, but the Ford tune in the 11-12 GT500 is not the same as the Ford Racing tune in the 08-09 GT500KR so that's plausible. Anyway, it's common knowledge the Ford Racing tunes are slightly more aggressive than Ford factory tunes (although Ford Racing tunes are still relatively conservative). Factor in aftermarket dyno calibration settings to that and it's a pretty good explanation.

Nice 40th. Did you sell your Tungston GT500?

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The idea that these GT500KRs are somehow underrated from a peak horsepower perspective has got to be a complete myth. I would chalk it up to dynamometer calibration, which I'm almost certain is different than what Ford uses. There's nothing particularly special about the cold-air kit and tune that comes on these cars.

What are the numbers for the KR's that you have seen?

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