Jpr5690

iTrader: (13)

is there any consensus on waht if any modifactions to this table should be for hot climates.. ive been reading about the iat becomming heatsoaked and causingfueling problems but do not know if this is sometinhg i "should" be mssing with

soundengineer

iTrader: (16)

http://www.hptuners.com/forum/showthread.php?t=6345

quite a ways into it....
IAT vs ECT complex cylinder charge Bias settings...which only seems to work on 2001/2002 F-body OS's
but it works...

Jpr5690

iTrader: (13)

yea i read that thread and my head hurts now.. is there a conclusion ?

Jpr5690

iTrader: (13)

ok so take the "0.79980 0.41992 0.28271 0.24365 0.21973 0.20264 0.18848 0.17578 0.16455 0.15381 0.14355 0.13428 0.12451 0.11523 0.10645 0.08984"
values in the complex cylinder bias table and just use 1.0 across the board????

LS1PoweredZ28

iTrader: (2)

Does anyone know why changing the bias only seems to work on 01+ cars?

Kevin

soundengineer

iTrader: (16)

1.0 has worked for me on my car and on many cars I have tuned...
I'm sure it could use some fine tuning on every car...but its a dam fine starting point and has solved many many issues

when you set the bias to 1.0 you should also set your entire OLFA table to 1.0 as it wil be almost dead on at all ECT...and make sure you set PE adders to 0 to start and fine tune with the IAT/ECT adders IF needed...and get your PE tuned in correctly before you mess with the adders

soundengineer

iTrader: (16)

something about GM being stupid in so many things they do and correcting it later cause they dont think you are gonna notice..LOL

Mat

See, we all say GM is stupid and then we ask questions about their OS and PCM's and tables and stuff. Maybe they aren't so stupid after all. We're learning what their engineers created... and slowly!

That being said, yes, they make lots of mistakes.

soundengineer

iTrader: (16)

stupid mistakes..LOL

in later years they populate the table differently.....but its still WAY off for their fueling calculations that thy use....

as far as I can tell the fueling calc uses both ECT and IAT and IAT is supposed to be les than 5% change from cold to hot with everything else being the same if I remember basic automotive science ...
so it makes sens to desensitize th calculation which overcorrects drastically when its biased too close to the IAT..

Jpr5690

iTrader: (13)

ok just to recap...

1: cylinder charge temp bias : set to 1 ACROSS THE BOARD
2: open loop eq ratio set to 1 across the board?
3:ect & iat pe adders set to 0 across the board

and just to be safe pe set to one across the board


now tune my pe using the wideband and make change sto the iat adder if nessiary


IS THIS CORRECT?

soundengineer

iTrader: (16)

1:yes
2:yes
3:yes
PE...set to DESIRED AFR...not to 1.0
you most likely want something in the 12.5~12.8 AFR range which is 1.170~1.148 range

tune PE with wideband......
make that know temp your set value(try to do it in colder air)
then adjust IAT adder for hotter days if necessary(probably not much if any)

and again...not funcional in all OS's on the bias table thing..have to try it to find out if it works on yours...
2001/2002 F-bodys work...98/99/00 dont(so try to upgrade from a 99/00 to an 01/02 OS if possible- 98's are SOL unless you want to do a bunch of wiring or order a painless harness

Jpr5690

iTrader: (13)

yea but since im just starting to tune my pe table shouldent i start somewhere and see what the wideband gets first them make changes .. i mean i guess it really dont matter: what ever i get on my 1st pull ill either have to raise or lower the pe to bring it in algin with what im looking for

also my car is a 2002


thanks for the help.. ill post back when i make more progress

-john

Jpr5690

iTrader: (13)

i dont see why i change my olfa to 1.0? wouldent that command a 14.7 afr at wot?

soundengineer

iTrader: (16)

no..your PE is commanding AFR for WOT....
PE/OLFA...which ever is richer..the pcm uses