What I can read from my i30 N
A small logger in the diagnostic port records the values below while I drive, about one to two readings per second each. This page lists what they are and shows what they look like on real drives. The car is a Hyundai i30 N with the 8-speed dual-clutch gearbox. It's a private project, nothing for sale.
Temperatures
- Coolant°CWarm-up and cooling under load
- Engine oil°CTakes much longer than the coolant to warm up – the better signal for when to push
- Gearbox oil°CWarms up much more slowly than the engine oil
- Intake air°CHot intake air means less power, e.g. after standing in the pits
- Catalytic converter°CRises quickly under full load
- Outside air°CCompare with the intake air to see how much the engine bay heats it
- Clutch 1 and clutch 2°CSee the gearbox section below
Example: a cold start
On this drive the coolant reached 90 °C after 8 minutes. The oil needed 11 minutes to reach 80 °C and settled at 87 °C. The gearbox oil is far slower: on a 7 °C day it was at 41 °C after almost 40 minutes of driving.
Engine and turbo
- Engine speedrpm
- Boost pressurebarAbove outside air pressure. On my drives over 1 bar within 0.6 to 1 second of full throttle
- Accelerator pedal%How far the pedal is pressed. Together with throttle and boost it shows how quickly the engine responds
- Throttle (target and actual) and engine load%
- Air-fuel mixture, target and measuredlambdaShows the engine running richer at high rpm to protect itself
- Ignition timing, overall and per cylinderdegreesIf the engine pulls timing on one cylinder (knock), that cylinder would show less than the others
- Fuel correction, short- and long-term%
- Fuel consumptionlitres / hour
- Fuel level%Jumps a lot while driving, only useful when standing
- Battery voltagevolts
- Engine torqueNmFound; the exact scale is still being checked
- Fuel pressure at the injectorsbarAbout 30 bar at idle, rising with engine speed
Example: a full-throttle pull, 2nd to 5th gear
Boost holds 1.05 to 1.16 bar up to 6,200 rpm. At the same time the air-fuel mixture goes from 1.0 down to about 0.72, and the measured value follows the target closely.
Gearbox
- Current gear1–8, R
- Next gear1–8, RThe gearbox prepares the next gear 1 to 2 seconds before it shifts
- Gear leverP, R, N, D, M
- Manual mode and paddle requestson / off
- Clutch 1 temperature°CDrives gears 1, 3, 5 and 7
- Clutch 2 temperature°CDrives gears 2, 4, 6, 8 and reverse
- Gearbox oil temperature°CSee temperatures above
- Limited-slip differential oil temperature°CProbably; still being checked
Example: the two clutches heating up
From a standstill into a full-throttle pull. Each clutch heats up when its gears are in use and cools down within about 20 seconds. Clutch 2 peaked at 94 °C in 4th gear.
Brakes, wheels and steering
- Brake pedalyes / no
- Brake pressurerelativeHow hard the brake is applied; the exact unit is still being checked
- Wheel speed, each of the four wheelskm/hShows ABS, locking wheels and wheelspin
- Vehicle speedkm/h
- Steering angledegreesAbout ±380° at full lock
- Acceleration and braking forceg
- Yaw rate, how fast the car rotatesdegrees / sCalibrated with the difference between the rear wheel speeds
- Cornering forcegUp to 0.6 g on my road drives so far
Example: an ABS stop from 83 km/h
Full braking, 0.89 g at the peak. In the hardest moment single wheels drop below the others: that is the ABS releasing them for a split second.
Tyres and suspension
- Tyre pressure, each tyrebarThe first two minutes after starting show stored values
- Tyre temperature, each tyre°CProbably in the tyre sensor data; not logged yet
- Damper settingsoft, sport, N
- Lights, doors, bonnet and indicatorson / off
Example: tyre pressures on a road drive
Cold, and after a 19-minute road drive. On track they rise much more.
| Tyre | Cold | Warm |
|---|---|---|
| Front left | 2.54 bar | 2.65 bar |
| Front right | 2.54 bar | 2.69 bar |
| Rear left | 2.36 bar | 2.44 bar |
| Rear right | 2.37 bar | 2.46 bar |
Speed per gear
Measured on my drives with the stock gearbox, on my wheels and tyres. Useful to know which gear a corner needs. Speeds above 250 km/h are left out.
| Gear | at 1,000 rpm | at 4,000 rpm | at 6,000 rpm |
|---|---|---|---|
| 1 | 8 km/h | 33 km/h | 49 km/h |
| 2 | 14 km/h | 54 km/h | 82 km/h |
| 3 | 20 km/h | 79 km/h | 118 km/h |
| 4 | 26 km/h | 106 km/h | 159 km/h |
| 5 | 33 km/h | 133 km/h | 199 km/h |
| 6 | 40 km/h | 160 km/h | 240 km/h |
| 7 | 49 km/h | 197 km/h | – |
| 8 | 62 km/h | 246 km/h | – |
Limits
- One to two readings per second. That is plenty for temperatures, pressures and the gear, but too coarse to analyse a single corner in detail.
- No GPS yet, so no lap times and no position on the track.
- The gearbox values used to stop for the rest of a drive after hard full-throttle runs. On the latest drive they didn't; I'm keeping an eye on it.
- Not confirmed yet: the unit of the brake pressure, the tyre temperature, the scale of the engine torque, the fuel pressure and the differential temperature. Cornering force and yaw rate are accurate to about 10 %.
Already running: a small display in the cockpit with oil, coolant, gearbox and clutch temperatures and boost. Next: a GPS logger for lap times and position.