LPG2CV wrote: ↑Fri Jan 03, 2020 9:42 am
Ok, at this point, it may help if you tell us what you want to achieve. Where you are coming from, and where you want to get to.
If you just ask individual questions, it doesn't provide a context to answer them.
^^This. we are only talking in generic terms, as we do not know the project or its goals. Without those we cannot estimate the effects of each variable or make suggestions if we have them and if you want them.
jonbill wrote: ↑Fri Jan 03, 2020 9:24 am
@PSIG where do you connect the MAP? engine side of the throttle or air side?
In order to use it as a load sensor, it must be reading manifold pressure — so after the throttle. This follows convention and Speeduino, which uses Speed Density as the primary basis for both fueling and ignition timing calculations.
@Joshuabenjaminm using load for ignition is always used for calculation when applied, except for absolute WOT on an NA engine, in order to apply best timing for best efficiency. Best efficiency means best performance (max torque, max power, max economy, etc). It applies to all. For other engines such as with power adders, load is used for benefit all the time, including WOT.
Fixed (1D) timing is only useful for engines that run at one speed and load. 2D timing only helps to compensate for the burn rate changes due to speed, in relative timing, turbulence effects and effective compression. This works well enough for engines not operated dynamically, such as static generators and some boats, etc. Substantial improvements in efficiencies are found by also adding load to the brew, and allows nearly unlimited manipulations for specific special purposes. Win, win … win.
My point in this is only to emphasize that an engine will run with fixed ignition, run much better with 2D timing, have another leap forward with load, and incremental additions from other data. At any given moment and conditions there is only one correct timing point, and as @LPG2CV said, more sensors (data) means finding that point easier or better or both. Whether you wish to apply that or need it for your project goals is entirely up to you.
David