sideways-FC

Can somone explain to me what ''load'' is exactly when it comes to tuning.I know its read in kpa through a map sensor and when the tb is closed the manifold is under vacume and it will read some were under 100 kpa and as the tb opens it lets more air in and it starts to read closer to 100 kpa and this tells the ecu the air density or load. but would somthing like driving up a hill change the load to. like how load bearing dynos are used for tuning to hold the car at a consent load while tuning. I geuss what im asking is load what your asking the engine to do like opening the throtle up to accelerate or is it also what the engine phisicly has to do like move the car or clim a hill.

beefhole

iTrader: (29)

When driving up a hill, you are putting more load on the engine than driving down hill. Makes sense right? You are loading the engine by asking it to fight gravity and move 1.5 tons. In order to keep going, you have to stay on the gas, meaning the throttle plates are opening more. This also means the tune moves "up" in the load maps. The RPMs are increasing as well. So the word "load" comes into play in both examples here.

When you are asking the engine to move the car on the road or dyno, that's when you are truly loading it. free revving in neutral will move the current "load" bar on the maps, but you aren't asking the engine to do anything. This is why you have to drive the car to tune it properly (or go on a dyno).

sideways-FC

so basicly you go up in load when your going up a hill or accelarating because your giveing it more throtle to make it do the work.

j9fd3s

iTrader: (3)

yes. basically load is airflow. the reason we call it load is because there are a few ways to measure it, so load is a common term.

some ecu's use the throttle position as the primary load, some use a map (manifold absolute pressure) sensor, some use an airflow sensor, and some use a combination.

RotaryEvolution

iTrader: (30)

when you dump a load in the toilet it takes energy, this could be compared to that energy. bigger the load, more energy applied.

sorry i had to, been in a wierd goof mood lately.

sideways-FC

would I ever have to worie about detination just siting in nutral free reving.

arghx

iTrader: (3)

there are more obscure and technical ways of determining load that are related to the amount of pressure inside the combustion chamber. These are often used to compare engines of different layouts, displacements, etc.

j9fd3s

iTrader: (3)

lol, its more like load vs bathroom fan speed!

generally no, you have to be WAY off somewhere. the other way to do it, is to have the trailing coils, or wires backwards