Calculating Instantaneous Net Power

[joecar]

Edit: This power calculation comes already provided by the EFILive V7 and V6 Scan Tools as the built-in pid "{CALC.POWER_RW}".
Edit: This was written a long time ago when EFILive V5 was current, which is why it contains references to "{SAE.J1979.VSS}".

Using EFILive's calculated PID feature, you can calculate the "instantaneous net road power" at all recorded sample points using the following equations:

(for sake of example, I'm using my vehicle's mass (3750 LB = 1701 kg))

Using Imperial units (mass in LB, VSS in MPH):
3750 * {SAE.J1979.VSS} * dx({SAE.J1979.VSS}, 6) / 8226.63

Using Metric units (mass in kg, VSS in km/h):
1701 * {SAE.J1979.VSS} * dx({SAE.J1979.VSS}, 6) / 12960.0

Notes:

a. Vehicle total mass must include driver and all payload mass (to be accurate, you must account for all the weight).

b. The constant number 6 is the dt factor in the derivative function; you may want to read up the EFILive help on this function and play around with some different dt values.

c. The constants 8226.63 and 12960.0 are due to the various conversion factors between Metric and Imperial units and between non-mks and mks units (m, kg, s: the default units of physics).

d. The above equations are arrived at from the standard physics definitions of velocity, acceleration, force, work, etc. (i.e. they do not include any empirical influence or corrections).

If the units used were the classic physics units (kg, m, s) then the
instantaneous net power at each sample point would simply be:

P = m . v . dv/dt

(m is in kg, v is in m/s, and dv/dt is the slope of the VSS "curve")

These equations calculate the instantaneous (at each sample point) net road power that's left over to accelerate the vehicle (i.e. after mechanical friction, road friction, air resistance, and anything else you can think of, has been overcome by engine power).

:?

[RoboGeek]

cool! But math makes my head hurt.. :roll:

Maybe I'll write that into some script and post it

[joecar]

cool! But math makes my head hurt.. :roll:

Maybe I'll write that into some script and post it

All you have to do is create a calculated pid containing either of the following equations (depending on if you want Metric or Imperial) which you enter by typing or pasting:

Using Imperial units (mass in LB, VSS in MPH):
3750 * {SAE.J1979.VSS} * dx({SAE.J1979.VSS}, 6) / 8226.63

Using Metric units (mass in kg, VSS in km/h):
1701 * {SAE.J1979.VSS} * dx({SAE.J1979.VSS}, 6) / 12960.0

Of course, you use your own vehicle weight instead of 3570 LB or 1701 kg.

This is like a "road dyno" using EFILive, if you get my drift...

[darkstar]

These calcs will get me a HP reading???

any testimonials to its accuracy?

[joecar]

I'm hoping that someone with access to a dyno will post their results.

[Highlander]

Dyno results are nowhere near....

Although the graph smooths out on the dyno, it shows around 30rwhp more than on the dyno graph...

And another thing the graph on the street is very very wavy.. anyway to correct that?

[Blacky]

Select "Generic" scan mode and only have a single PID (SAE.J1979.VSS} or {SAE.VSS} selected.
You should get a frame rate of about 20 per second in V5, and up to 40 per second in V6,- the faster the better.

(Note the speed difference in V5 to V6 is due to V6 supporting 115200 baud and V5 only supporting 19200 baud).

Also try changing the formulas to increase the time frame over which the power calculation is made. i.e. increase the second parameter of the dx() function.
i.e. increase it to say, about 10 or 12.

The higher the value the "smoother" the curve. But the less detail will be shown because the calculation is made over a longer time frame.

Paul

[joecar]

The Highlander,

Okay, there's a 30rwhp difference (I was looking to see feedback like this, thanks I do appreciate this);

Is this difference throughout the rpm range, or is it localized...?

Also keep in mind, the formula calculates HP using the laws of motion (i.e. it uses physics theory) and does not account for some things (e.g. tire deflection, and others...?), and does not do any corrections (for altitude or whatever) like some dynos do.

So, 30 rwhp is about 10% (or less maybe) of max, so it's not too far off.

But actually, could you post the pictures of both graphs somewhere...?

(It is usable enough to see an hp increase after doing a mod).

Thanks again for your feedback.
:)

[Highlander]

That is what I am trying to prove or something...

Its 30 in its max point... but throughout the whole band, another thing.. I used the weight of the drum and not the weight of the car... I hope I can smooth out the curve..

The curve is smooth on the dyno but on the street is very very ERRATIC...

[joecar]

The curve is smooth on the dyno but on the street is very very ERRATIC...


Are you saying that the calculated curve is smooth on the dyno and erratic on the street, or are you saying that the dyno's curve is smooth and the calculated curve is erratic...?

(... I do apologize... I am suffering from jetlag... we flew SYD to AKL on Saturday, and AKL to LAX on Sunday... :shock: :shock: )

Is there some place where you can post images of both the dyno curve and the calculated curve that you got...?

[Highlander]

The calculated graph from efilive is smooth on the dyno, but when run on the street is very erratic... Get me now? :D.

The way I see it is, since there are lot less variables on the dyno its easier to apply the force to the drum than to the street.. wheelspin? different waves of air?? maybe if instead of logging 24PIDs one logs 3 or 4 would get more frames per second and provide a much much smoother curve.

With the AT123 V2 I am getting 9.4 frames per second... I got with more PIDs 10frames/s out of an OBDI!!!! So.. I dont understand.

[Blacky]

The calculated graph from efilive is smooth on the dyno, but when run on the street is very erratic... Get me now? :D.

The way I see it is, since there are lot less variables on the dyno its easier to apply the force to the drum than to the street.. wheelspin? different waves of air?? maybe if instead of logging 24PIDs one logs 3 or 4 would get more frames per second and provide a much much smoother curve.

With the AT123 V2 I am getting 9.4 frames per second... I got with more PIDs 10frames/s out of an OBDI!!!! So.. I dont understand.

Select "Generic" scan mode and only have a single PID (SAE.J1979.VSS} or {SAE.VSS} selected.
You should get a frame rate of about 20 frames per second in V5, and up to 40 frames per second in V6.

OBDI (ALDL) is way faster than OBDII - always will be.
OBDII has too much overhead.
Typical ALDL frame contains 4 bytes of header and 64 bytes of payload.
Typical OBDII frame contains 6 bytes of header and only 6 bytes of payload.
So the OBDII data transfer rate is effectively halved by the top heavy J1850 protocol.

Regards
Paul

[Highlander]

The other thing is if I use the fast dynamic can I log faster using a lot less PID's??? LMK

I want to beta test a v6, but have not gotten a response... is it possible to get ahold of a V6?
LMK

THanks

[joecar]

I thought EFILive V6 was available in the download section of this website.

[joecar]

I thought EFILive V6 was available in the download section of this website.

Oh, I was wrong, sorry. :oops:

You may have to contact Blacky (Paul).

[Blacky]

The other thing is if I use the fast dynamic can I log faster using a lot less PID's??? LMK
THanks

Fast dynamic is fixed at 24 bytes of data at 5 or 10 frames per second by the PCM. Selecting less PIDs just means reducing the number of data bytes - it does not increase the speed.

Regards
Paul

[Blacky]

The calculated graph from efilive is smooth on the dyno, but when run on the street is very erratic... Get me now? :D.

The way I see it is, since there are lot less variables on the dyno its easier to apply the force to the drum than to the street.. wheelspin? different waves of air?

Here's two example charts showing Joe's hp calculations

The first chart, from a dyno run, is a supercharged LS1 and is fairly smooth. The dyno was a hub mounted dyno which provided very fine speed control over the engine.

http://www.efilive.com/upload/efilive_forum/images/blacky_hpdyno.png

The second chart, from a road run is a normally aspirated LS1 and is very erratic, during the run the rear tyres were "complaining" - they were on the limit of adhesion - maybe a little wheelspin.

http://www.efilive.com/upload/efilive_forum/images/blacky_hproad.png
[/img]

[joecar]

Paul,

Hmmm.... :?

On those 2 traces, expand the scales for VSS, RWHP, run time, and then replot with VSS and run time right above RWHP, and then repost (centre the traces around an upward slope mostly, and expand to fill most of the chart);

Please send me a table of MPH vs time points for the linear upward portions of each trace; I'll do some approximate calculations on paper....

Both traces seem to show the correct RWHP wiggles (matching the VSS wiggles), but the values seem too high.

Like I said, "Hmmm.... :? "

There's an explanation for "not-round", and we'll find it.
Joe

[Blacky]

Both traces seem to show the correct RWHP wiggles (matching the VSS wiggles), but the values seem too high.

Like I said, "Hmmm.... :? "

There's an explanation for "not-round", and we'll find it.
Joe

You were right Joe, the values were too high.
V6 had a bug causing it to use kmh instead of mph
(Thanks for finding the bug).
So instead of calculating at 100kmh it was calculating at 100mph.
I have updated the charts with the "correct" calculations.

Paul

[emarkay]

Paul, this would be a great "line item" in V6. A preset chart that uses this data and displays... Interesting idea....

Preset modes for specific applicaions - not just a PID display, but a calculated representation of an event.....

Or maybe It's too early in the morning for rational thoughts? :?

[Blacky]

Yes, you did get up too early, I have no idea what you are tolking about :?

[joecar]

I think he means having the HP calculation be included with V6
(unlike V5 where you have to paste it in);
and, it seems he is in luck, because it looks like it already is included :) .

I like how you included the gForce pid
(very cool for measuring braking mods).

Paul, if you can, can you post the new HP charts...
oh wait... it looks like you already updated them
(very happy to help out).

Regards,
Joe
:D

[2000ssnb]

I used to do this in ATAP with just acquiring VSS anf the time stamps
and the throttle position (as a check what my foot was really doing).

I converted to an excel sheet and did the calculation afterwards.

I found that you also need to take into consideration in the
mass (vehicle weight) the effect of accelerating rotating mass
(tires/wheels, drivetrain etc...) . This is different for each gear selected.

The factors for multiplying your actual mass (17"wheels, 3.42 gears)

1st gear: 1.2
2nd 1.12
3rd 1.085
4th 1.06

I also plotted a power friction loss curve based on an assumed cd
value. The power at the rear wheels you calculate does not include
the loss due to wind-resistance and wind (head wind or back wind etc.).
This needs to be added to the EFILive measurement to get a comparison
to the dyno reading because there is no wind-resistance to overcome on a dyno. Combined you can get pretty good results, assuming you numbers are close to actual (for example, at around 95 mph in 3rd
near 5700rpm, power peak area, the loss due to windresistance is about
70 or so Hp or more with no wind).

Gert

[Highlander]

IN that sense the TTS Powersystems dyno from datamaster takes into account all that ;) it works pretty darn well I suppose...

[joecar]

The formula P = m.v.dv/dt.k is measuring the power available to accelerate the vehicle after all the resistance/friction has been overcome; it does not include corrections for anything; it calculates the actual power to the road that is making the vehicle increase speed; it makes no other claims;

however, if you know the various corrections, you modify the formula and post it, someone with a dyno can compare the formula to their dyno and see how close it is.

[2000ssnb]

The P= m v dv/dt formula posted here assumes that m is constant.
However, due to all the rotating parts which have to be accelerated
the effective mass is actually higher than the static mass of the vehicle.
I posted above the multiplication factor for the first four gears with an
M6 and 17" tires, 3.42 rear. I derived these from the automotive tables
for V8 equipped cars. One can debate the accuracy of these factors
but they need to be taken into account for better accuracy.

Also, because in a road test, air resistance must be overcome, the
power to do this is also delivered at the rear wheels.
So on the road at 6000 rpm in 4th,it will give much lower output power than at 6000rpm in 2nd gear because of the speed difference and resulting air load difference. This effect does not show up on a dyno because the car is not pushing air out of its way - so dyno numbers should be much higher than this actual test.
The problem in road testing is that to get actual power readings there is little time because our engines run through 2nd gear in a hurry, yet
the air load is much less important at the lower speed (goes with v cubed)
One can get much better readings in 4th because because the engine spends more time there during a full throttle run,
however the air resistaqnce will make the power look really low near the
typical peak rpms of 5500....6000rpm. So, knowing the losses due to air and adding them can give the best results based on resolution etc.

So once you calculate both parts and add them you can get roughly what
a dyno would yield.

However, in actual driving, a head wind can make a difference as well as a tailwind etc.,.

Gert

[joecar]

Gert (2000ssnb),

I' not saying you're wrong and I can appreciate the fact that you took the time to look up tables of data; and you are correct that the formula does not consider air resistance (it measures what remains after air resistance has taken its bite);

All I'm saying is the following (this sounds funny because the following is a bit long...)...

The formula calculates the power left over after all the resistances, frictions and inertias have been overcome; the formula does not care what is propelling the vehicle; it uses the vehicle's measured rate of change of motion/velocity to calculate the net power that is remaining at the drive wheels after all the resistance and air friction has been overcome; if the vehicle is moving at a constant velocity, the formula gives zero power since the rate of change of velocity is zero;

I agree with you that rotational inertia (angular mass) influences angular acceleration, but it does not influence the vehicle's mass; the angular mass of a given powertrain and the torque developed by that powertrain's engine both determine the rate of increase of angular velecity of the whole powertrain within the vehicle; internal mechanical friction throughout the driveline subtracts from the available engine torque and so reduces the rate of increase of driveline angular velocity;

at the drive wheels (ignoring tire slip and deflection for a moment), angular force (torque) is converted to linear force; the whole vehicle's rate of change of velocity is determined by this force and by the vehicle's mass; air resistance subtracts from this force; so finally, after all the resistances/frictions have subtracted, the remaining force determines the rate of change of velocity of the vehicle (at that once particular instant in time);

if the vehicle is accelerating, the remaining force is positive;
if the vehicle is at steady speed, the remaining force is zero;
if the vehicle is decelerating, the remaining force is negative;

the formula does not take into account any losses between the VSS (which is where we're measuring the instantaneous speed, unlike a dyno) and the drive wheels; these losses are: tire slip, tire deflection, drive shaft twist, U-Joint flex, axle twist, differential gear friction, differential bearing losses, wheel bearing losses, transmission output shaft bearing losses; the formula comes from the physics definition of power and work; dynomometers use the same formula with correction factors and terms; the G-Force windshield mounted accelerometer uses the same formula (would anyone be willing to compare a G-Force power curve to an EFILive calculated power curve...? I am curious, I think I'll have to get one...)

if you don't have dyno access, the formula can be used to compare before and after doing a mod, provided you do the runs on the same stretch of road under the same conditions;

if you do have dyno access, there is no air resistance, so the formula (EFILive capture during dyno run) should come close to the uncorrected dyno results; someone on this thread (I think it was Highlander) found something like a 10% difference, which is not so bad considering the formula does not include losses between the VSS sensor and the drive wheels (a differential ring and pinion has a lot of mechanical friction due to the hypoid arrangement (non-intersecting centerlines between the ring and the pinion));

yes, a headwind makes you look bad, and a tailwind makes you look real good, as does going down a big hill); and you do bring up a very good point: air resistance is proportional to the speed cubed, so the net power will be less at higher speeds on a road test; the hard part is knowing the losses due to air;

if you capture a trace going up thru some speed (say 80 mph), and then on the same spot on the road you capture a trace going down thru the same speed (coasting, measures air resistance, road friction, and mechanical friction), and you subtract the two calculated power numbers at that speed (since the coast down number is negative), you will get an approximate flywheel power number (e.g. I got 260 - (-70) = 330); of course, this is approximate, and is based on being consistent, and picking a perfectly calm day, and doing both runs minutes apart;

also, while the engine is running it is consuming fuel which means the vehicle mass is reducing; but over a a short distance (1 mile say) the change of mass is very small compared the the vehicle mass, so it can be ignored;

good discussion, shows some people are thinking
(you sound like you might be an engineer...)

Joe
:wink:

[joecar]

The factors for multiplying your actual mass (17"wheels, 3.42 gears)
1st gear: 1.2
2nd 1.12
3rd 1.085
4th 1.06


Gert,

Would you please look up the factors for my car...?
My car is:
2001 TA WS6
275/40R17
3.23 axle,
A4 (1st 3.059, 2nd 1.625, 3rd 1.000, 4th 0.696),
Alum drive shaft

What about the Cd for it (with Ram Air hood)...?

Thanks, appreciate it.
:D

[2000ssnb]

Joecar,

These factors are called the "rotational inertia coefficient."

I dervied these from a handbook using some graphs etc.

There you multiply the gear you are in with the rear end gear
ratio. Since your transmission gear ratios
are bit higher than my manual gear ratios but your rear end
is a bit lower (3.23 vs. 3.42) the factors are probably
pretty much the same. I did this work over a year ago
at home on paper etc. and it will take me some time
to go through the procedure. Your wheels seem to be the same
etc.

I used 0.3 for our cd value but this is just an educated guess
based on "wedge shaped vehicles." I can't imagine that our
cd would be a lot worse,

Gert

[joecar]

Gert,

Yeah, our sleds are pretty aero.

Thanks for the rotational inertia coefficients, appreciate it.

[dbaxter_ss]

Something I think you guys forgot about to get an accurate HP reading is the amount of gas your car has. Without that your kinda robbing yourself of hp.

Adding in the gm.fuelrem pid to the formula * 6.350 ( weight of 1 gallon of premium gas ). Sorry metric guys I didn't lookup that weight.

So you need car weight, you and the amount of gas your car has: Since the car does somewhat accurately keep the amount you can get this by adding the gm pid.

HP = (((3554+({GM.FUELREM}*6.350)+195)*{SAE.VSS.mph})*d x({SAE.VSS.mph},12))/8226.63

compared to without
hp = (((3554+195)*{SAE.VSS.mph})*dx({SAE.VSS.mph},12))/8226.63

I would assume this would closely relate to a mustang dyno, so to get dynojet numbers /.9 ( mustang is 10% lower then a dynojet but supposed to be more real world load ) then /.85 drive train loss.

So in mine below.
381 /.9 = 424.2
423/3 /.85 = 499 fwhp ( AHHH SO CLOSE to 500 )

http://www.purplegto.com/files/hp.PNG

[dbaxter_ss]

Since I was bored, I figured I would just put down the HP, then the HP formula like I put above but put down all 3 change offset of 6, 10 and 12.

From waht I can see 10 and 12 dont make a much of a difference although over the given one and at 6 it makes a big difference.

http://www.purplegto.com/files/hp2.PNG

[joecar]

That's very true, accurate mass is critical to the accurate calculation of HP.
8)

[joecar]

Quite impressive: You're spinning to 6900 RPM...!! 8) 8) 8) 8) 8) 8)

Edit: corrected spelling of "RPM", oooopsy.... :oops:

[dbaxter_ss]

The rev limiters are set to 7000. On that run it hit 7003 :D

I am happy with that run more because it was climbing in HP up to 6900.

[Blacky]

Tips and tricks:

I know you are probably only displaying a temporary chart config to illustrate your point, but...

In the chart properties, try checking the "Split units" checkbox for each series. That way the "HP" will appear on it's own line and (depending on the height of the chart) long captions may become a little larger and easier to see.

Regards
Paul

[dbaxter_ss]

Kewl will try that next time :D Today was better anyway with .25 less saturday and .1 less wot today kicked her up from the 380 to 393 :D

http://www.purplegto.com/files/newhp.PNG

[joecar]

How close is this calculated power curve to what the dyno says...?

[dbaxter_ss]

Ha, to be honest I haven't been to a dyno with the SS in a while, most of the time I have been going with the GTO.

[joecar]

Derrick,
How many seconds does your SS take to go from 43 to 83 MPH on the chart that you posted here...?
What about on the street 0..60 MPH...?
I wasn't paying attention, does your SS have M6 or A4..?
Joe 8)

[dbaxter_ss]

M6/2k1/SS Vert
In this run 4.226 second from 42-83 according to efi :D I went digging through the logs I have on my laptop here and cant find any 0-60 runs :(, i will dig through some to see what I can find.
all the mods are on my site at http://www.2001camaross.com
just goto the mods link.

http://www.purplegto.com/files/42to83.PNG

[joecar]

You have a very cool car (for all the right reasons)!
8) 8)

[dbaxter_ss]

Just had to post a new best from today - VERY HAPPY
391hp using my calc from above for accuracy: 3554 (SS Vert ) gm.fuelrem and dx at 12. Heck even dx at 6 it was at 385 :D

40-80 in 3.8 seconds :D SWEET!!!

no 0-60 number because its an on ramp and I have to cross an intersection first.

http://www.purplegto.com/files/newbest391.png

[joecar]

He he he... Power rules...!!!!
:D :D :D

[BowlingSS]

[quote="dbaxter_ss"]Just had to post a new best from today - VERY HAPPY
391hp using my calc from above for accuracy: 3554 (SS Vert ) gm.fuelrem and dx at 12. Heck even dx at 6 it was at 385 :D

40-80 in 3.8 seconds :D SWEET!!!


Can I get a copy of your PID you set up? Did you change the sae_generic file or place it in the cal_pids file?
Thanks,
Bill

[BowlingSS]

Is this PID in 7.2.3? I see the old one but not the new one mentioned in this thread.

Bill

[joecar]

Derrick has the power formula dialled in pretty good. 8) 8) 8)

[BowlingSS]

Can you copy the cal_pid file you are using? I am not sure about the format.
Thanks,
Bill
:D

[dbaxter_ss]

THese should work for you
GTO
CTS-V
Z06
and
Vert SS

Just replace the 185 in the calcs below with your own weight.

I have the dx for 2, 6 and 12 then look at all three. the more pids you log the lower the dx. I usually look at all three. If you logging a bunch and do a 0-60, 2 will give the correct amount, but 12 will look like 100hp. Vice versa if you logging just a few things and do a 0-60, 2 will give 500hp when 12 shows 350.

I can tell you that using the Z06 12 dx below, on the mustang dyno it pulled 322, on the street we pulled 327 so its pretty darn close, better ITS REAL, everything that affects TRUE HP is truely affecting your output. So anything slowing down VSS like FRICTION, Aerodynmic which NO DYNO can see will affect EFI since its logging the change in speed from each logged amount.



# ================================================== ============================
# File details
# ------------
#
# This section defines various details about the file format.

*FILE

#Parameter Value Description
#---------- ---------------- ---------------------------------------------------
VERSION 7.1.1 File version
DECSEP . Decimal separator used in this file



# ================================================== ============================
# Units
# -------------------
# See sae_generic.txt for more information on the *UNITS section

*UNITS

#Code System Abbr Description
#-------- ---------- -------- -------------------------------------------------------------

# ================================================== ============================
# Add slot definitions here
# --------------------------------
# See sae_generic.txt for more information on "SLOT" formats
#
#Units Low High Fmt Expression
#------------ ------------- ------------- ---- --------------------------------------------------------------
*CLC-00-979
% -10.00 10.00 .2 "({SAE.SHRTFT1}+{SAE.SHRTFT2})/2"
*CLC-00-980
% -25.00 25.00 .2 "({SAE.LONGFT1}+{SAE.LONGFT2})/2"
*CLC-00-981
AFR 0.00 15.00 .2 "14.63/{GM.EQIVRATIO}"
*CLC-00-988
AFR 0 20 .2 "({CALC.BEN_TE1}+{CALC.BEN_TE2})/2"
*CLC-00-989
hp 0.0 400.0 .0 "(((3554+({GM.FUELREM}*6.350)+185)*{SAE.VSS.mph})*d x({SAE.VSS.mph},6))/8226.63"
*CLC-00-990
hp 0.0 400.0 .0 "(((3554+({GM.FUELREM}*6.350)+185)*{SAE.VSS.mph})*d x({SAE.VSS.mph},12))/8226.63"
*CLC-00-991
hp 0.0 400.0 .0 "(((3775+({GM.FUELREM}*6.350)+185)*{SAE.VSS.mph})*d x({SAE.VSS.mph},6))/8226.63"
*CLC-00-992
hp 0.0 400.0 .0 "(((3775+({GM.FUELREM}*6.350)+185)*{SAE.VSS.mph})*d x({SAE.VSS.mph},12))/8226.63"
*CLC-00-993
cylair 0.0 4095.9 .0 "{CALC.CYLAIR} * 1000"
*CLC-00-994
hp 0.0 400.0 .0 "(((3554+({GM.FUELREM}*6.350)+185)*{SAE.VSS.mph})*d x({SAE.VSS.mph},2))/8226.63"
*CLC-00-995
hp 0.0 400.0 .0 "(((3800+({GM.FUELREM}*6.350)+185)*{SAE.VSS.mph})*d x({SAE.VSS.mph},12))/8226.63"
*CLC-00-996
hp 0.0 400.0 .0 "(((3800+({GM.FUELREM}*6.350)+185)*{SAE.VSS.mph})*d x({SAE.VSS.mph},2))/8226.63"
*CLC-00-997
hp 0.0 400.0 .0 "(((3800+({GM.FUELREM}*6.350)+185)*{SAE.VSS.mph})*d x({SAE.VSS.mph},6))/8226.63"
*CLC-00-998
hp 0.0 400.0 .0 "(((3117+({GM.FUELREM}*6.350)+185)*{SAE.VSS.mph})*d x({SAE.VSS.mph},2))/8226.63"
*CLC-00-999
hp 0.0 400.0 .0 "(((3117+({GM.FUELREM}*6.350)+185)*{SAE.VSS.mph})*d x({SAE.VSS.mph},12))/8226.63"

# ================================================== ============================
*PRN - Parameter Reference Numbers
# --------------------------------
# See sae_generic.txt for more information on the *PRN section
#
#Code PRN SLOT Units System Description
#------------------------- ---- ------------ ---------------- ---------------- ------------------------------------------
CALC.LTAVG F601 CLC-00-980 % Fuel "Long Term Average"
CALC.STAVG F611 CLC-00-979 % Fuel "Short Term Term Average"
CALC.EQAFR F602 CLC-00-981 "AFR" External "AFR based on EQ 14.63:1"
CALC.BEN_AUTHAVG F609 CLC-00-988 "AFR" External "Ben Auth Avg"
CALC.SSHPTRUE6 F60A CLC-00-989 "kW,hp" Performance "SS TRUE HP 06"
CALC.SSHPTRUE12 F60B CLC-00-990 "kW,hp" Performance "SS TRUE HP 12"
CALC.GTOHPTRUE6 F60C CLC-00-991 "kW,hp" Performance "GTO TRUE HP 06"
CALC.GTOHPTRUE12 F60D CLC-00-992 "kW,hp" Performance "GTO TRUE HP 12"
CALC.MGCYLAIR F60F CLC-00-993 "cylair" Air "Millgrams Air mass per cylinder"
CALC.SSHPTRUE1 F610 CLC-00-994 "kW,hp" Performance "SS TRUE HP 1xz"
CALC.ctsv12 F611 CLC-00-995 "kW,hp" Performance "ctsv 12 hp"
CALC.ctsv2 F612 CLC-00-996 "kW,hp" Performance "ctsv 2 hp"
CALC.ctsv6 F613 CLC-00-997 "kW,hp" Performance "ctsv 6 hp"
CALC.z06-2 F614 CLC-00-998 "kW,hp" Performance "z06 2 hp"
CALC.z-6-12 F615 CLC-00-999 "kW,hp" Performance "z06 12 hp"

[BowlingSS]

Thanks for the info. I will give it a try. After a big meal I am also about 185...
What are these for:
CALC.LTAVG F601 CLC-00-980 % Fuel "Long Term Average"
CALC.STAVG F611 CLC-00-979 % Fuel "Short Term Term Average"

Bill

[dbaxter_ss]

A map that I have to see what my ltft average is for ltft1 and ltft2, same for the stft's.

[ringram]

Has anyone done a distance PID? For doing 1/4 Mile times?

Kind of make your own gtech thing.

[joecar]

Need the integrate function and some conditional operators to do this.

[Blacky]

The integrate function was in EFILive V5 - but it became difficult to calculate effectively so it was removed in V6 and V7.
The integerate function and some other V5 features will probably make their way back into V8 when it is released.

Regards
Paul

[joecar]

"V8" has a nice ring to it, doesn't it... :exactly:

[Garry]

*LOL* Yeah, V8 is the way to go! :)

Don't think a quartermile distance can be added too accurately ... once you have any wheel spin (e.g. on launch, or chirp the tires during 1-2 or 2-3 shift), you're numbers will be off ...

[DmaxHawk]

Sorry guys, I'm still not understanding how to calculate RWHP and RWTQ. I;m not sure where to put the formulas...Do they go in a file or do I put them in on the scan tool itself? Where exactly dot he formulas go? What PIDs needs to be selected? What else needs to be done?

If someone could make a step-by-step process starting from scratch on how to do this I would greatly appreciate it. :thankyou2:

Thanks
-Sal