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Has anyone else tested the actual engine horsepower of their Trackhawk? I measured mine on a dyno and was disappointed with the result. Interested to know if anyone else has done the same. Ian
 

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You wont be disappointed if you swap out the pulleys. Our vehicles should have come out the box like that rather then with the stock 707hp. The power and the pull will actually scare you, its game changing.
 

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Has anyone else tested the actual engine horsepower of their Trackhawk? I measured mine on a dyno and was disappointed with the result. Interested to know if anyone else has done the same. Ian
why disappointed? were you disappointed before you stuck on dyno? Ill guess not!
the rated 707 hp is crank HP or engine HP not finial drive numbers. after the power goes thru the all wheel drive you loose a bunch. All cars do all wheel drive is just a bit more. I forget the % but someone posted it here before.
Dyno should only be used for tuning anything else and its just a BS number.
 

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Discussion Starter · #4 ·
Thanks for your response. I'm aware I can improve the output of the engine, but, as stock, I was expecting it to deliver as advertised. Currently having a conversation with FCA about this.
 

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Disappointed because it wasn't anything like stated at the crank. I thought there was a problem with the output, hence checked on a dyno.
 

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Thanks for your response. I'm aware I can improve the output of the engine, but, as stock, I was expecting it to deliver as advertised. Currently having a conversation with FCA about this.
did you read my post? whats wrong are you way way down? the dyno should be around 550-560 HP but there are many factors in that number. what was your post you sheet
 

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Discussion Starter · #8 ·
Disappointed because it wasn't anything like stated at the crank. I thought there was a problem with the output, hence checked on a dyno.
 

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your off 50 hp that could be anything. different dynos do different numbers. man the list is long but your fine.
bigger question how did you check crank HP and not all wheel?
 

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Definition of terms:

"Crank hp/torque" would be achieved on an engine dyno...the engine on a test stand, out of the vehicle.

"Wheel hp/torque" is achieved on a chassis dyno. On AWD vehicles, some people do this with the front axle disconnected from the driveline, so those resulting numbers are a bit higher than when on a four-wheel dyno with all wheels delivering power, as in "stock condition."

Typically, you can expect a 20% (+/-) power loss in an AWD vehicle on a chassis dyno with all wheels delivering power. So 707 X 0.20 = 141 hp loss. Which equals 566 hp at the wheels.

Engine dynos show much less of a loss factor, because the engine is turning much less mass/resistance, but even that output number depends if the engine is being run with all accessories, or just the minimum to get it to operate.

Of course, all of these tests depends on the accuracy of the dyno(s) involved, as well as the weather, altitude, fuel used, the humans running the thing, etc.

Hope this helps.
 

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649hp at the crank/engine. Not sure how to attach the sheet, as it's too big.

the only way to test this is your motor was pulled out of the vehicle and tested in a engine dyno room.

I am going out on a limb and assuming you had your car on a chassis dyno and your tuner took your whp and multiplied it by a calculation he made up and gave you those numbers. Which is definitely not a way to get an accurate crank hp #. it also points the finger to your guy looking like an idiot.

If i'm right I would advise against talking to FCA about it as you're going to look incredibly foolish.

If i'm wrong and your motor was removed and tested in a engine dyno room then shame on me for assuming and keep us posted.
 

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Chassis dynos are an excellent tool for looking at a power delta before/after changes to a vehicle, as well as differences between vehicles.


I wouldn’t worry about absolute numbers. They are subject to interpretation, correction factors, less-than-real-world airflow, atmospherics, etc...


Take your car to the track. The trap speed will tell you if you’re actually down on power.
 

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You wont be disappointed if you swap out the pulleys. Our vehicles should have come out the box like that rather then with the stock 707hp. The power and the pull will actually scare you, its game changing.
I am no real gear head, just someone that enjoys cars of speed.

Help me understand, "swap out the pulleys".

So no need for upgraded fuel injectors, unlocking of PCM for tuning, thermostat, etc. etc... How would this affect shift points, if any?

What kind of output could someone expect from this mod?

Thanks in advance...
 

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I am no real gear head, just someone that enjoys cars of speed.

Help me understand, "swap out the pulleys".

So no need for upgraded fuel injectors, unlocking of PCM for tuning, thermostat, etc. etc... How would this affect shift points, if any?

What kind of output could someone expect from this mod?

Thanks in advance...
thats a trick question I am sure someone will say you can change the pulley and leave everything else alone. maybe you can maybe you cant but I def would not. Im gonna guess not many will.
 

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Threw my stock Trackhawk on my buddy's mustang Dyno last week. Averaged 566whp/542wtq.

These things heat soak like a mofo.

As was mentioned before, calculations from "crankshaft" to "wheel" power ratings (or vice versa) are only approximations, and your actual output may/will vary.

But, notice that my "20% loss factor" I mentioned earlier converts 707 crank hp to 566 at-the-wheels hp...and that's exactly what GraniteHawk's dyno runs averaged.

So, in this instance, the calcs worked out okay.

I agree that dynos are great for delta testing the effectiveness of new power-adder components. But dragstrip trap speed is also very good as a real-world measure.

I'd use both, if I had easy access.
 
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