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Old 06-30-2016, 06:05 PM   #61
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Quote:
Originally Posted by aidandj View Post
This doesnt work. Different turbos flow different amounts at different pressure ratios.

On sunday I went to the dyno with Ed. He has a gt2871. I have a td04-15g. I made like 160ft/lbs at 8psi. He made like 200 something.

You can look at compressor maps. Calculate the pressure ratio and see what the compressor flows at that ratio. It isn't exact but it gives you an idea.
I think that's mostly due to the compressor efficiency which will affect temperature out which was assumed constant in the super ghetto PR * NA HP equation. Just use that to get a ball park idea of HP per Psi but compressor maps are the way to go but it sounded like reading compressor maps were beyond the scope of the OP.
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Old 06-30-2016, 08:36 PM   #62
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Anyone asked what fuel (Pump vs E85) and ignition timing he's running?
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Old 07-01-2016, 06:29 PM   #63
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Default What HP at what PSI?

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Originally Posted by Kens_Clubman View Post
Anyone asked what fuel (Pump vs E85) and ignition timing he's running?
Doesn't matter. All engines pretty much make the same power at the same boost pressure regardless of other variables. It's called dynamic linearity. You can't argue with science.
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Old 07-01-2016, 07:40 PM   #64
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Took the words straight outa my head...........from yesterday

GET OUT OF MY HEAD CHARLESSSSSSSS
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Old 07-01-2016, 10:29 PM   #65
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Here is an overlaid dyno plot of 2 different setups at 8psi. This is why you can't compare.



Exact same MAP, 50ft/lb difference.
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What HP at what PSI?-80-hxnwotg_5497ed54d8dee680cb78036007d308372bbc0d31.png  
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Old 07-01-2016, 10:34 PM   #66
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Quote:
Originally Posted by aidandj View Post
Here is an overlaid dyno plot of 2 different setups at 8psi. This is why you can't compare.



Exact same MAP, 50ft/lb difference.
That's like, your opinion, man. Post some numbers to back it up.
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Old 07-01-2016, 10:47 PM   #67
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Quote:
Originally Posted by sixshooter View Post
Doesn't matter. All engines pretty much make the same power at the same boost pressure regardless of other variables. It's called dynamic linearity. You can't argue with science.
Can you explain this further? Or were you just joking.

Even the same car, same boost, same setup, makes drastically different power/torque with different ignition timing. I'll be running 16psi at 7000rpm from a c30-94 rotrex... are you saying I'll make 350whp regardless of my ignition timing, fueling, altitude? That doesn't seem right. Not trying to argue, just curious.

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Old 07-01-2016, 10:49 PM   #68
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Default What HP at what PSI?

Quote:
Originally Posted by thumpetto007 View Post
Can you explain this further? Or were you just joking.

Even the same car, same boost, same setup, makes drastically different power/torque with different ignition timing. I'll be running 16psi at 7000rpm from a c30-94 rotrex... are you saying I'll make 350whp regardless of my ignition timing, fueling, altitude? That doesn't seem right. Not trying to argue, just curious.

Thanks
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Old 07-01-2016, 11:40 PM   #69
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Quote:
Originally Posted by cyotani View Post
I think that's mostly due to the compressor efficiency which will affect temperature out which was assumed constant in the super ghetto PR * NA HP equation. Just use that to get a ball park idea of HP per Psi but compressor maps are the way to go but it sounded like reading compressor maps were beyond the scope of the OP.
It's more than just efficiency. Its bigger and moves more air. A gt40 will move way more air than a 2554. At the same psi. Even if they are both perfectly efficient.
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Old 07-02-2016, 12:15 AM   #70
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Old 07-02-2016, 03:05 AM   #71
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Old 05-02-2017, 11:01 PM   #72
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Quote:
Originally Posted by hi_im_sean View Post
Ran out of fuel up top, but this is on the motor im running with the trubo im using at the psi that im running at, tapering to the psi that it tapers to.

I don't know how I ended up down the rabbit hole to this thread, but this picture needs to come back into the limelight.
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