Camshaft and Injector Timing

[lt1z350]

The throttle blade closing is the Aisin TCM imposing torque limits on you.

Nope I finally got it figured out last night and now 100 percent other then the shifts. Amazing what one damn table does. lol I haven't made enough powe yet to hit tcm limit it can be logged and was showing engine still and trans s on shifts. When hits tcm limit it will say trans in place of engine. Now I am getting 100 percent I am sure I will hit it at some point. Which won't be an issue soon as sent a tcm from the car to a company to get supported so in the works.

[Sachs]

Hello All,

Renting a dyno thursday to try to finalize my tune on my C7 GS M7 FBO with a TSP Stage 3 VVT cam (235/239 LSA116 ICL112)

I've read there are possibly good mid range gains tuning SOI with a big cam.

Any advices on what I should try ? I was planning to do 5 or 10 deg increments from base table, possibly trying first around 340 deg around the 0.7 to 1.0g airmass to see the effect.

In my case my pulse width is below 4.0 ms (around 3.8ms at 2700ft 7000rpm, 0.92g, 32% fuel lobe) so modifying the SOI is not because of that, it's more to try to gain more torque, as so far my mid range is a little bit disapointing...

Thanks for your help

[lucas287]

Ok so now that I slept, I am sure start of injection occurs during the intake stroke and ends during compression.

Based on some light reading, it seems like it would be a good idea to start injection at WOT as early as possible (when exhaust valve closes) and inject fuel as late as possible at idle and decel.

any opinions?

so if this is the case, why can't we lower the idle values for a later injection? why are they 310ish when WOT is 340 and decel is 275? what happens if we make idle 275?

if we change the SOI to something like 180 or 160 does that constitute ultra lean burn / stratified?

finally, how closely will the SOI Base table be followed? is the pulse width calculated inside the tune based on the SOI value? does it spray harder, for instance, with a later SOI or just less or just right through combustion?

I know I'm resurrecting this thread from the dead! But I don't think (could be wrong) that clarity was ever brought to this theory you postulated Higgs. I know a few posts down you just recommended leaving it stock and only advancing to keep pulsewidth down, but would you mind expounding on those conclusions?

As others have mentioned I'm completely on board with the mechanics of WOT SOI timing. Makes great sense. But there's very little discussed about part-throttle where a lot of us average-type folks spend driving perfectly average vehicles. The SOI Base table seems to overlay with the VVT table and it's evident that SOI is advanced when the cam timing is retarded in the EGR range.

Like many others, I have zero'd out my VVT tables under 3,000 RPM. Correspondingly, I zero'd the VCP spark table under 3,000 RPM. However, there doesn't seem to be an adder to SOI based on cam position, so what i've done is normalize that area by smoothing and globally retarding (reducing) the values. But, before radically experimenting I wanted to see if someone had some hard experience or data to dissuade me.

Thanks in advance. (pun intended)