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C7 Z51 HP problem..

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Old Apr 12, 2024 | 06:04 PM
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Default C7 Z51 HP problem..

Hello, I have a C7 z51.
With exhaust downpipe and X pipe. both without catalyst.
KN replacement filter
And a Tune.
The truth is that the car works very well.
I have done several tests against a friend's C7. and even mine is a little faster.
Today I went to the dyno and I had a bad surprise.
I expected 15 or 20 HP more than stock. Stock is 466hp "supposedly according to the manufacturer" . Well, I was thinking about 490 hp or so.
The result was 442hp engine. and 317 to the rear wheels. with a torque of 585Nm
Why so little power? It is normal ?
The dyno is from the Maha brand. They are very prestigious.

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Old Apr 13, 2024 | 06:47 AM
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I have done the typical test from 40 to 100 MPH.
first in one direction of the road and then just in the opposite direction.
I always get values between 5.6 and 5.7 sec.
It seems like a good time. Is it possible that the Dyno is bad in this case?


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Old Apr 13, 2024 | 11:33 PM
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A dyno on a stock C7 is a little over 400hp at the rear wheels. So if you gained anything it would be around 420-430 at the rear wheels. Its 460 at the crank.
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Old Apr 15, 2024 | 11:32 PM
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A stock NPP equipped C7 (whether base or Z51) is 460 crank HP. If you got a dyno reading of 442 crank and 317 rear wheels then yes, you have a problem.
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Old Apr 17, 2024 | 06:59 AM
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Old Apr 20, 2024 | 05:53 PM
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confirmed the Dyno has a problem. I don't configure it correctly.
I have tried dragy. with the traction control on, 2 people riding and street asphalt, and I think it's not bad at all.
You can improve the 0 to 60... by disconnecting the control and making a good start...
What do you think of these numbers?

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