What makes an Economy tune?

[Power Hungry]

See if this calculator helps...

Also, I think you boo-boo'd your calculation. I think you meant 21.6º of rotation at 1800 RPM and 2 ms. In any event, the rest of your math is correct.

[soutthpaw]

Originally Posted by Power Hungry

See if this calculator helps...

Also, I think you boo-boo'd your calculation. I think you meant 21.6º of rotation at 1800 RPM and 2 ms. In any event, the rest of your math is correct.

yep we will call that a typo... ok thanks for the chart too

[907DAVE]

I like the idea of using the SOI delay map to add timing, but what makes this map so complicated(ms instead of deg).? Can I get a Clif Note version?

[cleatus12r]

The reason the map is so complicated isn't because of the time value in the table but the fact that time is fixed and engine speed varies. That means that the actual SOI degree variance increases as the RPMs increase.

For example:

At 1500 RPM, the crankshaft will rotate 9 degrees per millisecond.
At 2600 RPM, the crankshaft will rotate 15.6 degrees per millisecond.

Using the same RPM values and a similar delay value will give you a difference in overall SOI advance difference of 6.6 degrees at 1ms and it goes up with more delay as long as all the other SOI adders and maps stay the same. For example, if the delay is doubled to 2ms, the actual SOI advance doubles as well to 13.2 degrees.

I hope this makes sense....

[907DAVE]

Ahh...I see..... does seem like things could get a little hairy.....quick!




Hmm....

[Power Hungry]

Especially when building files for high RPM racing/pulling applications. A small change in the SOI Offset could end up being a large timing change at 4000 RPM.

[soutthpaw]

But your fuel still burns at a constant rate.. haven't found the numerical constant for that but you can't get the fuel to burn faster so burn rate vs milliseconds should be a constant... (unless you add or remove something like NOS or elevation less O)
EDIT: Life should be so simple.. wrong again see next post