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Author Topic: 800whp Seat cupra 2.0Tfsi Sadicupra.  (Read 4368 times)
TijnCU
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flying brick


« Reply #15 on: October 08, 2016, 12:51:59 PM »

Dude, dont freak out and read carefully what I wrote. Ethanol has a different afr for stoich. I know that most power will be made at leaner mixtures but then E85 is still more fuel to air than same lambda with petrol. I'm not claiming this is all true but I try to come up with a possible explanation for higher hp numbers in stead of flaming people right away.
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turbojohan
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« Reply #16 on: October 08, 2016, 01:14:49 PM »

Tijn is right, on E85 you can add more fuel to same amount of air and make more hp with same airflow.

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DT
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« Reply #17 on: October 08, 2016, 01:25:32 PM »

TijnCU:

if we disregard all you have said about AFR it would still be silly to talk about E85 since one thing that has been questioned in this thread is the fuelling capacity in a TFSI engine without extra injectors.
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gman86
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« Reply #18 on: October 08, 2016, 02:49:05 PM »

You do realise that E85 has a lower calorific value than standard petroleum? As in, 33% less? So to make the same power, you need 33% more fuel.
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Carsinc
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« Reply #19 on: October 08, 2016, 05:21:48 PM »

Yes, that is my point, I did not think the Fsi stock fuel system could support more then 700ish on the big side.
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vwaudiguy
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« Reply #20 on: October 08, 2016, 10:11:27 PM »

9:1 AFR will make the car not go anywhere and quite possibly even misfire

True story.
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"If you have a chinese turbo, that you are worried is going to blow up when you floor it, then LOL."
TijnCU
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flying brick


« Reply #21 on: October 09, 2016, 01:03:46 AM »

Sure, I'm aware of the lower btu of ethanol. But the fact remains that you make more power on e85 with a turbo engine as long as you can get the fuel in. You put all this power gain towards octane?

I noted that the a4 dtm had an extra injector ecu listed in the mods, so maybe the owners can elaborate about fueling.

If you disagree with my theory its fine but then you basically say the power claims for this 75lbs/min turbo are total bullshit. (But you rather tell the small guy he's bullshit?)

Here is some more math since it is sunday and it rains outside  Grin

Thermal energy of Gas = 19,000 BTU/lb
Thermal energy of E85 = 13,475 BTU/lb

Lets assume a consumption of air @ 100lbs/hr

100lbs/hr / 14.7 AFR = 6.802 lbs/hr of gasoline @ 19,000 BTU/lb = 129,238 BTU @ Lambda of 1
100lbs/hr / 9.76 AFR = 10.246 lbs/hr of E85 @ 13,475 BTU/lb = 138,065 BTU @ Lambda of 1

So you can see that the final thermal energy output is greater even though E85 has less energy per volume due to the fact that we are using more of it per pound of air.
« Last Edit: October 09, 2016, 05:26:02 AM by TijnCU » Logged

prj
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« Reply #22 on: October 10, 2016, 03:55:16 AM »

Sigh...

Ethanol chemical formula is C2H6O. It already has an oxygen atom attached to it. Gasoline does not, as it consists of hydrocarbons (CxHx).
This oxygen atom means when running E85 is a little like running nitrous built into the fuel. Not as dramatic of an effect, but nonetheless.
Add to it the fact that E85 upon evaporation supercools the intake charge, resulting in intake air temperatures of down to subzero at the intake valves, strongly compressing the incoming air.

This is why you make more power on E85.

The very basics with tuning engines is that OXYGEN makes power (even though chemically this is not quite correct).
Provided you have enough fuel supply, it is the amount of OXYGEN that dictates the power you can make.

The second component is ignition angle efficiency, which dictates how much power you extract from the fuel-air mix.
Due to E85 being extremely knock resistant and running very low EGT due to the cooling effect, you can basically run close to 100% efficiency (MBT) all the time.
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TijnCU
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flying brick


« Reply #23 on: October 10, 2016, 04:57:28 AM »

Well, your chemical explanation is perfectly in line with my analysis that there is less added oxygen required for the same power output right? The stoich AFR and my btu calculation tells this as well. If we do not consider overall efficiency differences there will be about 6,5% more energy generated from a stoich burning E85 mixture on the same amount of external "air".

But the original question I tried to answer was (and remains) is it possible to make 900hp on a gtx3582r?
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prj
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« Reply #24 on: October 10, 2016, 05:52:46 AM »

I am quite sure the dyno numbers on this are out of touch with reality.
The compressor just does not flow enough.

Independent dyno testing on something less happy than an out of cal dynojet will confirm, I'm sure.
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frankmabo
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« Reply #25 on: May 28, 2017, 06:32:20 AM »

How does that intercooler fit its 4.5in thick, you guys must have way more room than us.
How did you make 900hp without added injectors? What octane fuel? That turbo must be
working very hard, those power levels seem out of reach of that turbo.

Turbo is has a custom 9 blade turbine wheel, turbo is 105% maxed out, juggling overspinning but the bearing system is super tough.
I have 3 huge +1500cc meth injectors supplementing part of that fuel.
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vdubnation
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« Reply #26 on: May 28, 2017, 08:00:55 AM »

I am quite sure the dyno numbers on this are out of touch with reality.
The compressor just does not flow enough.

Independent dyno testing on something less happy than an out of cal dynojet will confirm, I'm sure.

I agree completely i m sick and tired of all these cars claiming these super inflated numbers some of these goons i ll pay to have the car shipped to USA to be put on a dyno thats trust worthy of .
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gman86
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« Reply #27 on: May 28, 2017, 10:01:34 AM »

I agree completely i m sick and tired of all these cars claiming these super inflated numbers some of these goons i ll pay to have the car shipped to USA to be put on a dyno thats trust worthy of .

Seems common in a lot of countries where tuning isn't as mature as other places. There were guys in Lebanon shouting 470WHP with meth from a turbo rated to 420PS (414BHP) on 102RON where most folk are getting 410-430BHP  Roll Eyes Their defense is usually "it's because we can tune this ECUs better than you guys".
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Carsinc
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« Reply #28 on: June 17, 2017, 11:38:43 AM »

I swear to god the biggest reason I want a dyno is to break hearts.
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nyet
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« Reply #29 on: June 17, 2017, 08:46:37 PM »

I swear to god the biggest reason I want a dyno is to break hearts.

Admirable.
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