Is SD worth it without the Custom OS?

[FstBlkZ28]

Is it really worth going to speed density tuning if you don't load the custom OS that lets the computer alter VE's, A/F, and whatever based on IAT's and stuff. (I'm not sure of all the specifics on what can be altered). Just wondering b/c I don't want to go through all the trouble of doing the AutoVE tune, and then a week later the car running like crap b/c the IAT's are warmer and the humidity changed.

Reason I ask, is b/c I don't have commercial ... and I'm out of money :bawl:

[Tordne]

One model of HSV came from th factory MAFless (Speed Density). I don't think the weather thing is too much of a concern. If you intend to return to Closed Loop fuel mode the LTFT trims will pretty much take car of the weather related changes (if any).

The only thing you will really be missing (aside from the cool things in the custom OS's) is the dual spark maps (high and low octane).

Make the jump ;)

[TAQuickness]

with your mod's, I'd go for it.

I've been running OLSD for about a year. I'm using a V3 OS, but don't utilize the IAT offset's or dual spark maps (yet). The most I've seen my AFR's drift due to weather is ~1%

[FstBlkZ28]

One model of HSV came from th factory MAFless (Speed Density). I don't think the weather thing is too much of a concern. If you intend to return to Closed Loop fuel mode the LTFT trims will pretty much take car of the weather related changes (if any).

The only thing you will really be missing (aside from the cool things in the custom OS's) is the dual spark maps (high and low octane).

Make the jump ;)

So I'd run into problems if I ran Open Loop SD then? Hell I guess I can always throw it back if I'm not happy with it.

[FstBlkZ28]

with your mod's, I go for it.

I've been running OLSD for about a year. I'm using a V3 OS, but don't utilize the IAT offset's or dual spark maps (yet). The most I've seen my AFR's drift due to weather is ~1%

Ok, thats reassuring. Thanks!

[Tordne]

The other thing that negates the weather is:

Because you have the tool you too will become possessed and will log religiously every drive that you go on from here on in...

Therefore any changes in weather will be caught in the log and changed accordingly in the VE table ;)

LOL (but I'm serious!).

[FstBlkZ28]

Therefore any changes in weather will be caught in the log and changed accordingly in the VE table ;)

LOL (but I'm serious!).

Meaning I'd be constantly updating the tune? lol

[joecar]

The VE Table cell units are g.K/kPa where the K accounts for intake air temp and kPa accounts for manifold absolute pressure; PCM measures BARO on startup and uses this in VAC calculations, so everything is accounted for...

i.e. if done right, the VE tune will not be affected by [most] weather changes.

[joecar]

Meaning I'd be constantly updating the tune? lol
You do want to get your money's worth from your purchase of EFILive, don't you...:cheers:

[FstBlkZ28]

You do want to get your money's worth from your purchase of EFILive, don't you...:cheers:

:muahaha: of course!

[Chris81]

The VE Table cell units are g.K/kPa where the K accounts for intake air temp and kPa accounts for manifold absolute pressure; PCM measures BARO on startup and uses this in VAC calculations, so everything is accounted for...

i.e. if done right, the VE tune will not be affected by [most] weather changes.
Why would the car i'm tuning currently go so lean on a hotter day after I dailed in the VE pretty close a couple days before? The car was setup for AutoVE tuning (SD and OL)

Is it because of open loop?

[ringram]

the pcm tables arnt 100% accurate, so your afr will go off a little, you can try to get to the bottom of the charge blending, or other tables. But often IMO its easier to adjust table A00014 in OS3 to get it in line. There is some info on this, but I run 1% adjustment per 10*C.

[Highlander]

you know... i have seen drifts of 7-10% easily from night to day when humidity gets to dew point and such at night.... there are some nights where there is NO Humidity that it doesn't drift.... i am working on that still...

[Highlander]

Why would the car i'm tuning currently go so lean on a hotter day after I dailed in the VE pretty close a couple days before? The car was setup for AutoVE tuning (SD and OL)

Is it because of open loop?
No.. this could be because of IAT Heatsoaking. check that out...