Fuel cut & ignition retard

[JTVOLVO]

I have been looking in the Megamanual but have not found if it possible to use coolant temperature to cut fuel or retard timing such as the rev limiter can do. Can anyone direct me on this issue?

Thanks,

James

[grippo]

The only way fuel is affected by coolant temp is during warmup. However, you might be able to add an extra temperature to the coolant temp array, say 200 deg F when you normally run 180 deg F at operating temperature. Then the engine would stay in permanent warmup mode, but you would set the correction factor at that temperature to 100% (no correction). Then if it ever went past 180 the correction factor for the 200 deg point would start coming into play and you could set it to a low correction (even 0). If you wanted an instant correction you could add 2 points, say 198 and 200, then you could set it up to do nothing at 198 then go to 0 (fuel cut) at 200). I don't know what staying in permanent warmup mode would do in other areas, but you could try this.

Spark retard is similar. There is an extra advance for spark when coolant is cold and it generally goes to 0 as you reach operating temperature. It uses the same coolant temp array as above, so you could do the same thing with spark, set the correction to 0 deg at 180, then put in -deg retard at 200 deg. However, you might have to modify the ini file to allow you to use negative numbers, I'm not sure.

[JTVOLVO]

Ok, thanks. I will look into those options.

James

[JTVOLVO]

I am not sure how to change the temp in the cooling temp array in warmup wizard.

James

[grippo]

I am not sure how to change the temp in the cooling temp array in warmup wizard.

James

You don't change them in the wizard - look in the Other Tables - there is a coolant temperature table menu.