[Megahurtz]

If translating to SOI/EOI numbers in the ECU. Basically, that cam card says your Intake Valve opens at roughly 366 SOI and closes at roughly 130 EOI. On the exhaust stroke the exhaust valve is still open until about 2 degrees after TDC(358 SOI). Now that is at .050 lift so its not the exact position, but it is about where it starts to matter.

Another thing to remember is the velocity of the air charge and how it moves in the engine/valves/combustion chamber. Air is elastic. So there isn't a firm line of when you should start injection, at least not definable by looking at a cam card. This is where the dyno comes in. But my comments in this thread are still accurate and true.

Example, if you're exhaust valve is still open until 2 degrees past TDC (358 SOI) but you start injecting fuel at 380 SOI, you're spraying fuel for 22 degrees of crank rotation where the exhaust valve is open during the exhaust stroke. Some of this fuel will just fly out of the exhaust port. As long as EOI is not dropping to the point of causing incorrect mixing of fuel and air, which will be seen as a loss of power on the dyno, you don't need to back SOI up where it throws fuel out of the exhaust port to bring the EOI higher than 180.

As a GENERAL rule. SOI of 370 or less and an EOI of 160 or less is perfectly fine on stock cam LT4. This even translates to cammed cars but that is where you need to start testing on the dyno to see if the airflow characteristics of the setup prefer an earlier SOI or not. It all depends on the air velocity and how it behaves since air is "elastic" in nature.

Based on the output of the SOI calculator image, the output would say start spraying at 326 SOI and stop spraying at 27 EOI which would be 5 degrees before the spark plug ignites if you want 22 degrees of timing. This is completely wrong and will damage your engine if you actually tried to run this duration.