Stock SRT dyno - 558 rwhp and 515 torque

mnc2886

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Didn't people throw a fit when the Edmund's dyno test only got 558 to the wheels and Ralph came on Twitter and said if you close the hood, it would've been a more accurate 580? Hmm.......
 

SilveRT8

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If dynoed in fourth gear with the same 1.00:1 ratio, shouldn't the new 3.55 gears ( 16% steeper) show less HP vs the Gen IV with 3.07 rear gears ?
My Gen IV showed 545 hp and 504 tq stock, I'm no expert on this but I find these numbers to be about right.
 

Jack B

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The losses are virtually inconsequential

If dynoed in fourth gear with the same 1.00:1 ratio, shouldn't the new 3.55 gears ( 16% steeper) show less HP vs the Gen IV with 3.07 rear gears ?
My Gen IV showed 545 hp and 504 tq stock, I'm no expert on this but I find these numbers to be about right.
 

ACRucrazy

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I Dynod my 08 with 4600 miles on it 2 weeks ago. Hight flow cats and corsa cat back.
558/525
 

DMan

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Seems inline with the 640 and the estimated 12-15% driveline loss. Some might be disappointed but it's what's to be expected. The gen5 isn't a car for HP bragging. It's a track car. I mean my GT500 is rated at 662 and dyno'd at 602 at the wheels, which is common so they're a strong 662, the gen5 is probably a finely tuned exact 640. But I'm sure future options will raise the number for those looking for more brutality. Thanks for sharing the vid.
 

ACRucrazy

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I bet we will see some higher numbers after others get their hands on them with some miles on the clock. But again the dyno is a tool, there will be differences. Would be nice to see a 570 stock IMO.
 

Torquemonster

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That's bang on for 640hp. We are bound to see higher once they get a few miles on them. Of course we're also bound to see higher numbers on more friendly dynos too, but trap speeds tell what you are really making.
 
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Nine Ball

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Yes, rear gearing ratio DOES affect dyno numbers. I've done and witnessed this many times, on many cars. Going higher numerically in gear ratio (3.07 up to 3.55, in this case) will certainly show a lower hp with the higher 3.55 gear set. In the GM world, it was common to go from 3.42 up to 3.73, and that would usually cost about 10-12 rwhp on a dynojet. But, the car would run quicker with the new gears. Dynos don't mean much, only before/after comparisons on the same dyno mean something.
 

hou99gts

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My 09 did 556/531 in Austin with 1600 miles on the clock Tony, I hope there is a big difference in the dynos. It wouldn't be a direct comparision, but maybe I should put mine on Hennessey's dyno to compare (almost at 11k miles now).
 

bluestreak

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Keep in mind also that it will benefit Hennessey more to show a lower baseline and higher output after the mods. So expect to see the fan much closer to the car as well. This IS Hennessey we are talking about.
 

Jack B

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It is inconsequential, I have had 3.07, 3.33 and 3.55, they all dyno within 5 hp. Tryi ng to push a tire/wheel combo with a high moment of inertia will mean more. You can tie the car down in a way that skew the results even further.

Yes, rear gearing ratio DOES affect dyno numbers. I've done and witnessed this many times, on many cars. Going higher numerically in gear ratio (3.07 up to 3.55, in this case) will certainly show a lower hp with the higher 3.55 gear set. In the GM world, it was common to go from 3.42 up to 3.73, and that would usually cost about 10-12 rwhp on a dynojet. But, the car would run quicker with the new gears. Dynos don't mean much, only before/after comparisons on the same dyno mean something.
 

ACRucrazy

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Hennessy put one on the Dyno back in Jan also for Road & Track. They didn't use any cooling fans and the engine was heat soaked.
Ralph said something about the no fans, then the Youtube video was removed the following day. It put down about 527 & 499 to the tire if I recall.

This latest Dyno at Hennessey (video in the first post) was the same HP as the Edmunds car put on the rollers in Jan that caused all the noise online about it being a low number when the "stock" ZR1 hit the dyno at 580 or whatever.

http://www.youtube.com/watch?feature=player_embedded&v=bXcA6Q0M80w
 

V10TT

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Keep in mind those are STD. corrected numbers not SAE. Around a 3% difference.
 

SnakeBitten

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That's bang on for 640hp. We are bound to see higher once they get a few miles on them. Of course we're also bound to see higher numbers on more friendly dynos too, but trap speeds tell what you are really making.

Trap speeds is where its at I agree. We have yet to see any Gen V Viper hit closer to 130mph in the 1/4 like the old Gen IV's did so I don't know if that's an indication that the car isnt working as well in the straight lines as the old car. We know its better in the twisties. Maybe its just too soon to speculate either way until we get a bunch more 1/4 passes by the owners.
 

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