Guys,

Do any of you have any tricks to help my tune a good idle with my 74219 cam? Trying to get rid of some of the "lopyness".

 

Biggest thing I found is to make sure you have enough timing and also to make sure your fueling is correct around idle. With those big cams, your fueling around idle can get tricky, so the WB will come out pretty useful there.

 

Closed or open loop idle?

 

Both, closed and open...

 

Craig - whats WB?

 

WideBand O2 sensor.

 

To get a stable idle in closed loop you'll need to adjust the PID o2 look-up tables. They are important for preventing the ecm from overcompensating with the fuel correction (rich lean oscilations are annoying).
Other than that, get a wideband and like Craig said, add like 10 degrees of timing in the idle area. That should help a lot for getting ready to tune the part throttle stuff. Then WOT.

 

Good info. ... What do you think a good timing would be at idle? Would I change that in the Spark advanc table?

 

JPrevost

Which way would you go with the O2 lookup tables to get a more stable idle? would you want the O2 to look for a richer mixture? (raising the table value)

 

What tables are the "O2 lookup tables" in 6E, I'm using TunerProRT.

 

O2 Error Reduction Gain Vs. Airflow
That's the table you should play with. Try shifting the table both ways and see how it effects your o2 x-counts and voltage.
I'm not going to give you all the answers (I'm starting to sound like Grumpy ).
You should only focus on 1 table at a time, 1 change with these tables should be all it takes to notice a difference. Once you've gotten a feel for things, put it back to stock values and then modify the following tables in the same manner;
Integrator Delay Vs. Airflow
Integrator Delay Multiplier Vs. Error, this table will be similar to the 1st table so it doesn't matter which one you adjust, just take notes and datalog with comments. It should only take you an evening to get a good grasp on how to modify these tables correctly.
Keep us posted on your results.

 

Awesome info. for a newbe. I will start to play... Thanks.

 

jackballs529
Member

Registered: Jun 2004
Location: Buffalo, NY
Posts: 51
Car: 1987 Iroc-z
Engine: 355/Edelbrockhds/lpe219cam/superram/ headers/24lb.inj/2400TC/formatochip
Transmission: 700R4/3.27 9-bolt


Change that it throws the threads off

I'm not a mod but I am just suggesting