Cengineer

Can you convert the old "time for peak cylinder pressure" to btdc in "simplified tuning" (regarding the new Osiris update)?

I took some logs and have as much as 44° btdc in some low load (and rpm) areas, not sure if this makes sense and wanted to double check.

Or maybe someone can supply a conservative base ignition map? Would greatly appreciate this

04 G35 coupe powerlab St

Thank you

bealljk

iTrader: (13)

44 degrees seems high but at full vacuum and low rpms I can see it. I dont run anything higher than 35 in my -14psi (in*hg) cells between ~2k to redline rpms.

In reality, I dont know that I've ever put my engine in this area of the map so I dont overthink nor spend much time on it.

Cengineer

In general, as load and rpms increases, your btdc decreases linearly as well?

So idle area 16-17° btdc, ramps up to 35° around 2k-3k rpms then tapers to 12° near redline and high load (conservative ignition timing)

Sorry, I don't have another way to double check my work (besides for those logs I took)

Thank you

bealljk

iTrader: (13)

generally speaking timing will decrease - mine isnt linear, looks more like an inverted log curve. Every engine and every setup is going to be a little different. If I remember correctly my engine likes to idle around 12-14 degrees.

The best thing you can do is go get your engine dyno tuned.

maxowner

For an understanding of how the factory timing tables work, read this http://www.romraider.com/forum/viewt...p?f=65&t=15017

Cengineer

Thank you, will read this over a few times