Ad: Log Dyno - Measure Horsepower & Torque from your Datalog

keninger

Specialist
Sep 11, 2018
66
11
0
Ride
335i E92 N54
Log Dyno is now available for both Android and iOS

On iOS you either have to copy or download your logs to the folder of Log Dyno in "Files", or you can share csv files directly to Log Dyno which will open up the measurement right away.

 

keninger

Specialist
Sep 11, 2018
66
11
0
Ride
335i E92 N54
Another measurement spot on, confirmed by dyno.

24751

24752
 

keninger

Specialist
Sep 11, 2018
66
11
0
Ride
335i E92 N54
Can not load mhd CSV files ‍♂

I have received your email and I was able to open the MHD datalog no problem on both Android and iOS. What issue do you encounter while trying to use a csv file for measurement?

This is the measurement I just assumed the environmental values and additional weight, obviously these numbers are not accurate due to the lack of information on the measurement environment, but I was able to open it up and this is how the curve looks like.
26923
 

gmagnus7

Corporal
Dec 3, 2018
174
73
0
Ride
135i N54
Is there anyway to make this app account locked vs by phone? I just upgraded my smartphone and it wants me to buy it again in Google play.
 

keninger

Specialist
Sep 11, 2018
66
11
0
Ride
335i E92 N54
Is there anyway to make this app account locked vs by phone? I just upgraded my smartphone and it wants me to buy it again in Google play.

Is can be purchased through Google Play/Apple App store, so you need to log in with the account you have purchased it with and then you can download it again to any device for free. As long as you log in to the account you used to purchase the app.
 

gmagnus7

Corporal
Dec 3, 2018
174
73
0
Ride
135i N54
Is can be purchased through Google Play/Apple App store, so you need to log in with the account you have purchased it with and then you can download it again to any device for free. As long as you log in to the account you used to purchase the app.
Yea it works now, but it was asking me to buy it again for some reason. Maybe GooglePlay hadn't synced my purchases yet or something. Oh well no issues now.
 

keninger

Specialist
Sep 11, 2018
66
11
0
Ride
335i E92 N54
Yea it works now, but it was asking me to buy it again for some reason. Maybe GooglePlay hadn't synced my purchases yet or something. Oh well no issues now.

Yeah I am sure it is Google Play account related. I am glad it works now.
 

Chrysheight

Lurker
Nov 11, 2017
20
2
0
San Jose, CA
Ride
2011 E93--N55 6MT
There is a large variation when changing the "log data RPM step". Seems like +- 40whp/torque when going through the steps. Can't you just find a step that would be closest to the dyno numbers when showing your examples?
 

keninger

Specialist
Sep 11, 2018
66
11
0
Ride
335i E92 N54
There is a large variation when changing the "log data RPM step". Seems like +- 40whp/torque when going through the steps. Can't you just find a step that would be closest to the dyno numbers when showing your examples?
Usually the "Auto Smoothing" works the best, but it really depends on your datalog, for example with an MHD log you have a lot of data, and with a JB4 log you have less "dense" data, because data collection rate is lower.

With log data rpm step you usually want to go low, but as low when you start getting spikes.

If you need help, email me at [email protected] and send me your log, I will look at it for you and help you which smoothing/log data rpm step is the best for your logs.
 

keninger

Specialist
Sep 11, 2018
66
11
0
Ride
335i E92 N54
Can't you just find a step that would be closest to the dyno numbers when showing your examples?

Auto smoothing is for this purpose, this is what usually gives the best results. To make sure your datalog is optimal for measurement, make sure your rpm curve is smooth and have no dips or bumps, as it throws off numbers, and changing log data rpm can filter it out, this is why your numbers can be different.

This log is not good for measurement, because those dips/spikes throw off the peak numbers:

28968


This is considered a clean log:
28969


But as you can see the first one is an MHD log and the curve is much more "detailed" and the second one is a jb4 log with much less data.
 

2007BMW335i

New Member
Jun 27, 2019
3
0
0
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2007 BMW 335i AT
For the person saying using this app on a dyno would be the most accurate way to check it obviously has no idea how the app works. It uses a lot of calculations but the most important one is how fast does it accelerate the total vehicle weight. On a dyno there is no vehicle weight or air resistance factored in, it's just measuring torque at the wheels and using engine rpm to calculate horsepower, the app couldn't possibly read the same as the dyno it's on. But the numbers derived from running on a smooth level road should be close to what a chassis dyno reads. Head wind or tail wind will also make a difference to the app.
 

keninger

Specialist
Sep 11, 2018
66
11
0
Ride
335i E92 N54
For the person saying using this app on a dyno would be the most accurate way to check it obviously has no idea how the app works. It uses a lot of calculations but the most important one is how fast does it accelerate the total vehicle weight. On a dyno there is no vehicle weight or air resistance factored in, it's just measuring torque at the wheels and using engine rpm to calculate horsepower, the app couldn't possibly read the same as the dyno it's on. But the numbers derived from running on a smooth level road should be close to what a chassis dyno reads. Head wind or tail wind will also make a difference to the app.

You are right, this is how the app works, but you can get very accurate numbers compared to a chassis dyno, for example I got almost exactly the same numbers
29137

29138


The log was a street pull which I got on the day of dynoing the car.

If you use a log from the dyno, you need to zero out the frontal area so the wind resistance is taken out of the account and you can dial in the dyno reading factor until you get the numbers from the dyno or play around with weight. You will get the same curve which could be usefull for calculating optimal shift points for example.
 

muly

New Member
Apr 19, 2019
6
1
0
United Kingdom
Ride
335i
Just downloaded app, and run staggered tyre setup (265/35/19 rear) 235/35/19 front, the app only has option to input 1 tyre size,do i justuse rear size ,as there is a 20bph difference?
 

keninger

Specialist
Sep 11, 2018
66
11
0
Ride
335i E92 N54
Just downloaded app, and run staggered tyre setup (265/35/19 rear) 235/35/19 front, the app only has option to input 1 tyre size,do i justuse rear size ,as there is a 20bph difference?

There is a significant difference in tire diameter between the front and rear. In this case use a tire size that would be the avarage of the front and rear tire size, it is for speed calculation and rpm is in direct connection with the rear wheel.
 
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keninger

Specialist
Sep 11, 2018
66
11
0
Ride
335i E92 N54
Hi!

i bought your app on Android and somehow i cannot set it up properly.

I am running a DCT car so i changed the gear ratios
i upload a CSV like this one:

I get weird results.

Can you help me to configure the app properly?

Hi!

Yes sure, email me at [email protected]

also please send me a screenshot of your measurement graph, the bottom right contains important information, if something is set up incorrectly I will most likely see it right away.