[Sephanite]

Where is the sport display getting its power readings from?

[NISFAN]

Originally Posted by Sephanite

Where is the sport display getting its power readings from?

Works it out from things like boost pressure/Air flow sensor/injector duty, revs, etc.

And no it is not very accurate.

[Sephanite]

Originally Posted by NISFAN

Works it out from things like boost pressure/Air flow sensor/injector duty, revs, etc.

And no it is not very accurate.

so a tune connected to it wont vary the figure?

[Meeeotch]

Interesting.

[tdizzle]

Originally Posted by Sephanite

so a tune connected to it wont vary the figure?

Not unless it's the PPK.

[Elk]

The display is merely pre-programmed eye-candy. It is not measuring anything.

[rallybull]

does it really need to measure the output in order to be accurate? Hasn't engineering reached the point where you can calculate something like power output based on a set of given input parameters?

[dinonz]

Originally Posted by rallybull

does it really need to measure the output in order to be accurate? Hasn't engineering reached the point where you can calculate something like power output based on a set of given input parameters?

You can predict relatively well I think to a degree. From memory, aircraft engines use about 0.45 lb/hp/hr so basically you can work out the power produced based on fuel rate. But it's still ballpark, because atmospheric conditions will play a part.

[300hp]

Here is my take on this. I have heard 2 PPK installs. When I first bought the car I had no PPK. My gauges showed 320/320. At no time did those sport displays show me exceeding 300/300. Never.

I then had my PPK installed in April and my gauges showed 320/400. At that stage my hp would max out and my tq never exceeded 332.

Now I just got my PPK reinstalled today with the new DME and my gauges show 400/400. My hp peaked at 335 today, exactly 335, not even 340, which would have been cool.

I think these displays are pre programmed but they use some smart algorithms to determine what to spit out. If you install your own tune outside of the BMW ecosystem the gauges will not work because its outside the parameters set in those algorithms.

I think within the defined parameters from BMW the displays show you information that is reasonably accurate. Notice I did not say accurate, but accurate within reason

[Sephanite]

Great! Thanks for the info

[BL 5]

[QUOTE=300hp;14614027]Now I just got my PPK reinstalled today with the new DME and my gauges show 400/400. My hp peaked at 335 today, exactly 335, not even 340, which would have been cool./QUOTE]

Good news! Couple questions....

Was there a problem with your original MPPK?
Did you feel any more power with updated MPPK?
Was there a charge for this?

[300hp]

[QUOTE=BL 5]

Originally Posted by 300hp

Now I just got my PPK reinstalled today with the new DME and my gauges show 400/400. My hp peaked at 335 today, exactly 335, not even 340, which would have been cool./QUOTE]

Good news! Couple questions....

Was there a problem with your original MPPK?
Did you feel any more power with updated MPPK?
Was there a charge for this?

Yes there was a problem with my car and one of the ways to fix it was replacing the DME. The DMEs were retooled recently and I just lucked out by getting one of the these retooled ones. Everything was done under warranty. See thread below

http://www.f30post.com/forums/showthread.php?t=879819

I still need more sit time before I can say this new set up is faster than the old. 15hp over 320 of the same may be tough to pick up from a butt dyno.

[Elk]

Originally Posted by 300hp

I think these displays are pre programmed but they use some smart algorithms to determine what to spit out. If you install your own tune outside of the BMW ecosystem the gauges will not work because its outside the parameters set in those algorithms.

This is a fair assumption, as is your thought the gauges are a fair approximation of what is going on.

[BL 5]

Originally Posted by 300hp

I still need more sit time before I can say this new set up is faster than the old. 15hp over 320 of the same may be tough to pick up from a butt dyno.

What you don't have that 100 miles in yet so you can conclusively tell is you've got more 'punch'??

Ha ha, just kidding.

The dyno won't lie, looking forward to seeing those results.

[300hp]

Originally Posted by BL 5

What you don't have that 100 miles in yet so you can conclusively tell is you've got more 'punch'??

Ha ha, just kidding.

The dyno won't lie, looking forward to seeing those results.

Sadly today I did not go over 320hp, no matter what I tried

[300hp]

After numerous tests today I can confirm I do not have the new PPK. Full throttle, 6800rpm yielded 320hp all the time. Only once did the hp go to 335hp. Only twice has it gone to 335hp since I got the car on Wednesday.

It's good to know on some random occasion I can get 335hp (assuming its not a software error), but it's a leap of faith for me to think this is the new PPK. 320hp is all I have under my control, the extra 15 comes and goes as it pleases.

[Elk]

Please do not base your conclusion on the silly sport display. It is not measuring anything, it is a pre-programmed guestimation.

If you really want to know what the car does, put it on a solid, real dyno and check.

[300hp]

Originally Posted by Elk

Please do not base your conclusion on the silly sport display. It is not measuring anything, it is a pre-programmed guestimation.

If you really want to know what the car does, put it on a solid, real dyno and check.

Elk you are not a fan of the sport displays, lol.

However nothing beats dyno results and since we are still waiting the launch control videos, I expect it will be a long wait for the dyno results.

[Elk]

The display is cute, but is not real. I admit being unimpressed with something that pretends to be an objective measurement, but is not.

[300hp]

Originally Posted by Elk

The display is cute, but is not real. I admit being unimpressed with something that pretends to be an objective measurement, but is not.

I just want to try one more thing before I concede defeat on this. If we know what the hp/tq graphs are like and we have input on throttle position, driver mode setting shouldn't it be fairly easy to deduce how much tq and hp the engine is making at any given time? I think the sport graphs are just as good at being indicative as the mpg graphs. What are your thought on this Elk

I am hoping the rest of the physics gurus, like drob can also chime in. Maybe he is busy face palming himself on the s4 vs 335i thread.

[Elk]

Originally Posted by 300hp

I think the sport graphs are just as good at being indicative as the mpg graphs.

MPG is easy to calculate as there are only two values, both easily obtained as actual measurements.

Calculating horsepower and torque is going to be, at best, an estimate based on a large number of variables none of which are measurements of power. For example, throttle position is only that - it only indirectly indicates the power which may be produced.

Then there is the variability of mass produced engines. Having seen many "identical" cars on the same dyno produce significantly different results (but consistent with the same car), I know there is no generic engine parameter we can measure to accurately predict a given engine's power.

The sport displays can reasonable be expected to read within plus or minus 10%, but I am afraid this is about as good as they can get.

[300hp]

Originally Posted by Elk

MPG is easy to calculate as there are only two values, both easily obtained as actual measurements.

Calculating horsepower and torque is going to be, at best, an estimate based on a large number of variables none of which are measurements of power. For example, throttle position is only that - it only indirectly indicates the power which may be produced.

Then there is the variability of mass produced engines. Having seen many "identical" cars on the same dyno produce significantly different results (but consistent with the same car), I know there is no generic engine parameter we can measure to accurately predict a given engine's power.

The sport displays can reasonable be expected to read within plus or minus 10%, but I am afraid this is about as good as they can get.

Absolutely agree

The sport displays can only be indicative but cannot be said to be accurate due to the variables you indicated.