LS2 VE Table values???

[redhardsupra]

The VE table is not really a volumetric efficiency table, but rather an airmass table.

correct, however airmass changes with things like pressure and temperature, thus airmass, while more expressive and descriptive, it is not as universal. VE (the theoretical one) is the purest form, as it is independent of atmospheric conditions. So you really have to look at VE, GMVE, airmass, and airflow forms to get a really good feel for how the car is running.

[GMPX]

Oh no, not the airmass debate, lets get Paul and Ben Strader in on this one .

Hey, we just write the software, we don't tune cars all day, whatever works for you guys we will change it to, I guess I was thinking along the lines of that the native 0 - 4096 does not relate to anythng we know in the LS1, but those that use aftermarket ECM's as well would be familiar with a VE% table, even though it's not a true VE table......oh no, here we go.....

Cheers,
Ross

[joecar]

I'll take raw 0-4095.

[redhardsupra]

ok, since i have admin's attention...
so is the 0-4095 an internal value, how it's stored in the pcm? i'm concerned for the LS2 guys, cause they got not that high to go with it, if stock you get 2.7, and peak is 4.1, that's not much, especially with FI.
same concern goes for the IFR table--63.95lb/hr? c'mon, my grandma could use bigger injectors and she's dead...
are these things gonna be addressed in COS? this would make all FI GTO guys (and theres a lot of them!) convert to EFILive

[Acer]

Ross,

I have no interest in protracted debates, just making the software as user friendly as possible & getting the car tuning right .

Tried to send you a PM yesterday but it bounced because your inbox is full. This was about the value of 4096 you quoted. I have never actually seen such a high value in an LS2 table before (see http://ls1-australia.com/forum/viewtopic.php?t=3904 as an example). Is this the maximum value GM will permit in the table but not actually used? The maximum I have seen using other tools on my LS2 is ~ 2530 (gm*K/kPa I think). This would explain the low VE% in your table & is a trap if people start thinking 4096 corresponds to 100% efficiency.

Cheers,

Michael

[GMPX]

O.K, see screen shot, this is the raw numbers, we will be happy to change them to show this instead of the theoretical VE%.

Yes PM box was full Acer, sorry about that.

Injector flow change is not an easy one, from what I can see it would involved a fair amount of code changing. 63.95lb/hr is the mathematical limit using the scaling GM have for the injectors.

Cheers,
Ross

[GMPX]

O.K, Paul got it figured out, how does this look now It was so obvious I feel rather silly

Cheers,
Ross

[Black02SS]

Ross, can you have settings in the tuning tool similar to how we have for LS1's for those that want multiple options? I don't care personally as long as there is something there to change. :lol:

[Acer]

Wonderful Ross - thanks very much for following it up . Only other minor comment is that like all earlier versions of Flashscan I think you are a factor of 1000 out if the units are gm*K/kPa which I always used to compensate for in my calculations. I'll double check this & let you know if what I recollect is correct.

IMHO these units are enough in the VE table & I wouldn't worry about calcualting % VE.

Cheers,

Michael

[Acer]

Paul & Ross,

I have checked my earlier calcs & believe your VE values are a facor of 1000 out (should 1000 greater) to correspond with the units. Suggest you do your own check on the conversion of the values in the ECM & see what you come up with.

Thanks,

Michael