Silver'nStripes
Member
Looking for some help with some data logging issues.
I run a sintered iron slipper clutch, so I use data log to help tune the clutch on the launch. The butt dyno is only so accurate!
I don't have the ability to log input shaft rpm, so I use the vehicle speed to calculate it. The I'll compare that to the engine rpm to try to determine how much the clutch is slipping and when it locks up.
It's super helpful to be able to tell exactly when the tire moves, after that I'm mostly focused on what happens in 1st gear.
For a while this worked great. However at some point the vehicle speed log started getting all wonky. When I'm on the 2 step, and for a while after the car leaves, the vehicle speed jumps around at nonsensical values. Then it jumps instantaneously up to the correct value and is fine for the rest of the run. The speedometer doesn't reflect what the data log shows.
Here's on of the data logs, ignore the slow 1-2 shift lol. Right around 62 seconds looks like when the car left, the vehicle speed is doing weird things before and after.
At some point a while back I installed a WOT Box, I'm not sure if that caused this? I don't think the PID that I am logging with has changed, but I'm thinking about making a new configuration file with every vehicle speed value I can find. Maybe one of them will work.
Other than that, maybe a sensor is dirty or broken? Not sure if this data comes from the vehicle speed sensor or the speedometer.
Planning on going to the track this Saturday, appreciate any ideas.
I run a sintered iron slipper clutch, so I use data log to help tune the clutch on the launch. The butt dyno is only so accurate!
I don't have the ability to log input shaft rpm, so I use the vehicle speed to calculate it. The I'll compare that to the engine rpm to try to determine how much the clutch is slipping and when it locks up.
It's super helpful to be able to tell exactly when the tire moves, after that I'm mostly focused on what happens in 1st gear.
For a while this worked great. However at some point the vehicle speed log started getting all wonky. When I'm on the 2 step, and for a while after the car leaves, the vehicle speed jumps around at nonsensical values. Then it jumps instantaneously up to the correct value and is fine for the rest of the run. The speedometer doesn't reflect what the data log shows.
Here's on of the data logs, ignore the slow 1-2 shift lol. Right around 62 seconds looks like when the car left, the vehicle speed is doing weird things before and after.
At some point a while back I installed a WOT Box, I'm not sure if that caused this? I don't think the PID that I am logging with has changed, but I'm thinking about making a new configuration file with every vehicle speed value I can find. Maybe one of them will work.
Other than that, maybe a sensor is dirty or broken? Not sure if this data comes from the vehicle speed sensor or the speedometer.
Planning on going to the track this Saturday, appreciate any ideas.
