Interesting info on B3702 Injection timing

[joecar]

Hi Joe

I believe the injector timing is in crank regress and relative to TDC on the compression stroke?

Foe example on the LS2 the advance is 490 degrees when cold and 220 degrees at normal running temps, so the timing events for the LS2 are as follows:


Engine cold

Inj fires. 130 BTDC. CLOSED INLET VALVE
IVO. 16 ATDC
ICL. 118 ATDC
IVC. 40 ABDC


Engine hot

IVO. 16 ATDC
ICL. 118 ATDC
Inj fires. 140 ATDC. INLET VALVE BEGGINING TO CLOSE
IVC. 40 ABDC

Hi Gelf,

That does make sense (relative to TDC compression stroke)...

The LS2 injector timing is directly in degrees... makes visualization easier...

The LS1 injector timing is in milliseconds, so I have to convert that to degrees based on rpm:

offset[°BTDC] = 720 * Toffset * RPM/120000

where Toffset is in ms,

range of Toffset B3702 is 0° to 8°, so offset[°BTDC] range is 0° to 288° (at 6000 rpm)... does this make sense...?



BTW: oh, your IVO would be 16° BTDC (to give you ICL 118°).