Scangauge HP numbers. WHAT THE !@#$?!
03-29-2008, 11:31 AM
#12
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Since we can measure wheel HP then we must multiply by 1.33 to get crank....
Such that for KrusTTy:
213.75 HP x 1.33 = 285 HP
I was multiplying my wheel by 1.2 so my crank HP was really down.
Both my Vag-Com HP (corrected by 1.11 for the ****) and my (uncorrected) Butt-Dyno HP are 225 HP wheel.
Thus I am getting 225 H x 1.33 = 300 HP Crank
I am much much happier now. I knew I was higher than the 270 HP I got from the SG.
The SG does not know that I have a **** and thus the crank HP that it provides is low by the **** 1.11 factor.
Taking the SG output & correcting for the ****:
270 HP x 1.11 = 300 HP
gives the same value as using the 1.33 drivetrain factor in going from wheel to crank.
This answers all of my questions.
BC
213.75 HP x 1.33 = 285 HP
I was multiplying my wheel by 1.2 so my crank HP was really down.
Both my Vag-Com HP (corrected by 1.11 for the ****) and my (uncorrected) Butt-Dyno HP are 225 HP wheel.
Thus I am getting 225 H x 1.33 = 300 HP Crank
I am much much happier now. I knew I was higher than the 270 HP I got from the SG.
The SG does not know that I have a **** and thus the crank HP that it provides is low by the **** 1.11 factor.
Taking the SG output & correcting for the ****:
270 HP x 1.11 = 300 HP
gives the same value as using the 1.33 drivetrain factor in going from wheel to crank.
This answers all of my questions.
BC
03-29-2008, 11:53 AM
#14
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You're missing the **** & BlueFlame. Here are my performance mods....
* APR 93 Octane Chip
* Stage III ModShack VTDA, ****, BM
* tCarbon FMIC kit
* EvoHeatShield Phenolic Spacer
* BlueFlame Exhaust
* 42DD 3" Downpipe w/high flow cats
* Wayne's 90deg O2 adaptor
* HyperBoost adjustable DV
* Forge SAMCO DV Relocation kit
* Forge SAMCO Silicone upper Boost hoses
* Forge Stage 1 & 2 ShortShift kits
* ECS DogBone mount kit
* Deka 15lb Battery with MMP attachment kit
* Autometer Boost Gauge - Vent mount
* Forge billet Aluminun TT dimpled Shift ****
* Stage III ModShack VTDA, ****, BM
* tCarbon FMIC kit
* EvoHeatShield Phenolic Spacer
* BlueFlame Exhaust
* 42DD 3" Downpipe w/high flow cats
* Wayne's 90deg O2 adaptor
* HyperBoost adjustable DV
* Forge SAMCO DV Relocation kit
* Forge SAMCO Silicone upper Boost hoses
* Forge Stage 1 & 2 ShortShift kits
* ECS DogBone mount kit
* Deka 15lb Battery with MMP attachment kit
* Autometer Boost Gauge - Vent mount
* Forge billet Aluminun TT dimpled Shift ****
03-29-2008, 12:04 PM
#15
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But by this time I have already gone beyond the peak HP......
<center><img src="http://pictureposter.audiworld.com/105167/2nd_3rd__4th_gear_hp_comparison.jpg"></center><p>so there's no need to really push the car this hard. The figure above shows the peak HP value for my car for 2nd, 3rd, & 4th gear. Notice that the peak HP increases slightly as the gear goes up and the peak moves to lower RPMs.
BC
BC
03-29-2008, 12:07 PM
#16
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do you like the gauge in the vent? i put my on a pod right above the first middle vent. i like my
vent too much to sacrafice it. if you want some pix i'll snap some and send it to you
03-29-2008, 12:12 PM
#17
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In the vent works great for me since I'm using Steve's mounting ring.....
which allows air to blow out around the gauge. If I didn't have Steve's ring I most probably would not have sacrificed the air and would have mounted the gauge somewhere else. It gets hot down here in the summer and I need my A/C vents working.
BC
BC
03-29-2008, 12:14 PM
#18
There's a reason the call it driveline "Loss"...>>
Start from the beginning.... A stock 225 hp (crank)TT normally dynos in the mid to 160 to mid 170hp range (crank). 225 x .75 = 168.75 so we're pretty much on the money there with a 25% loss..
Again, using KrusTTy as an example, Scan Gauge reading of 285 x .75 = 213.75 which is within a HP or 2 of his ACTUAL wheel dyno numbers..
You are assuming the Torque is calculated exclusively by the MAF and plugging in your .11 correction which I don't think is accurate. The calculation, I'm sure, takes in several other calculated parameters to arrive at a Torque (and consequently HP) number..
Again, using KrusTTy as an example, Scan Gauge reading of 285 x .75 = 213.75 which is within a HP or 2 of his ACTUAL wheel dyno numbers..
You are assuming the Torque is calculated exclusively by the MAF and plugging in your .11 correction which I don't think is accurate. The calculation, I'm sure, takes in several other calculated parameters to arrive at a Torque (and consequently HP) number..
03-29-2008, 12:29 PM
#19
There are many more factors involved....>>
According to the ME Motronic Engine management guide (Bosch) the following factors have some say:
Acccelerator pedal travel (TPS)
Engine speed
Cylinder charge factor (air mass)
Engine and intake air temps
Mixture composition
The Microprocessor employs this data as the basis for quantifying driver demand and res[ponds by calculating the engine torque required for compliance with the drivers wishes.
When converting the required engine output figure to the parameters for actually controlling engine output, that is:
The density of the cylinders air charge
the mass of the injected fuel and
the ignition timing
Since you have reduced the measured air charge with a ****, but increased the mass of injected fuel with a 4 bar I'm suspecting this is more of a wash than a pure .11 correction you are assuming.
Bottom line is all inputs are determinants in how much power can be made (and reported by the Torque calculation)..
<img src="http://images115.fotki.com/v663/photos/7/7305/776256/Sensordiagram-vi.jpg">
Acccelerator pedal travel (TPS)
Engine speed
Cylinder charge factor (air mass)
Engine and intake air temps
Mixture composition
The Microprocessor employs this data as the basis for quantifying driver demand and res[ponds by calculating the engine torque required for compliance with the drivers wishes.
When converting the required engine output figure to the parameters for actually controlling engine output, that is:
The density of the cylinders air charge
the mass of the injected fuel and
the ignition timing
Since you have reduced the measured air charge with a ****, but increased the mass of injected fuel with a 4 bar I'm suspecting this is more of a wash than a pure .11 correction you are assuming.
Bottom line is all inputs are determinants in how much power can be made (and reported by the Torque calculation)..
<img src="http://images115.fotki.com/v663/photos/7/7305/776256/Sensordiagram-vi.jpg">
03-29-2008, 12:30 PM
#20
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I'm on the bandwagon with you on this one. Totally agree now that......
I am using the 1/0.75 = 1.33 DriveTrain Loss (DTL) factor. Just looking at the same number from the bottom (wheel) instead of from the top (crank).
As I posted above, I'm totally copacetic with you. Everything falls in place for my car.
SG = 270 HP x 1.11 (****) ---> Crank = 300 HP
Vag-Com = 203 x 1.11 (****) x 1.33 (DTL)---> Crank = 300 HP
Butt-Dyno = 225 x 1.33 (DTL) ---> Crank = 300 HP
The SG includes the DTL which Vag-Com does not. This explains the difference betwenn the two when they are both using the same TQ data from the ECU.
Now that I know this I have all my ducks in a row.
Thank you again Steve.
BC
As I posted above, I'm totally copacetic with you. Everything falls in place for my car.
SG = 270 HP x 1.11 (****) ---> Crank = 300 HP
Vag-Com = 203 x 1.11 (****) x 1.33 (DTL)---> Crank = 300 HP
Butt-Dyno = 225 x 1.33 (DTL) ---> Crank = 300 HP
The SG includes the DTL which Vag-Com does not. This explains the difference betwenn the two when they are both using the same TQ data from the ECU.
Now that I know this I have all my ducks in a row.
Thank you again Steve.
BC