OK, how do you tune for idle? Mine smells of gas bad, and I have huge knock retard. But, off idle, it runs awesome, no timing retard. I am stumped.

Also, my cam bucks a bit when I first start it until it warms up and starts using the sensors. How do I tune it better for that?

I have tunercar, and datamaster.

I have a 385, AI heads cam intake, pacesetter longtubes, I have lots of stuff in my motor. Its broke in now, at about 2300 miles. Just put synthetic in. Just looking for some ideas here.
Thanks!
Cody

 

You can pull some timing to get rid of the surging. As for the rich at idle, you need to have a wideband so that you don't get it too lean. Do you use your MAF? If so, you can make the adjustments in that table.

 

yup, still use the screened maf sensor. And the internet jockies said I couldnt! hehe...
So could I do that on the dyno? I am going to try to tune it on the dyno with some help, could I just tuen the idle too before I dyno tune it?

 

no to hijack, but what tables (tunercat specifically) do you look at to tune in open loop with?
I've seen where you can use the afr x 10 tables, but I can't seem to find those, are they called something else?

 

I'm sure you could get a wideband reading and tune the car at idle on the dyno.

In tunercat, the table that you're looking for is called "open loop afr". You would also need to use the PE table to tune with (% added at WOT).

 

ok so the open loop afr is just idle and cruise and is not referenced for wot correct?

 

Unless you have disabled closed loop operation, open loop will only be used for the short while after you start the car, ie before things heat up to proper operating conditions.

 

ok, so ive disabled closed loop because of my cam and the fact that itd only run decent for about 20 minutes before the O2s would screw everything up. so even though the o2s arent technically functioning for closed loop duty, do they still try to regulate the car to the values stored in the open loop afr table? will just tuning that table help me out?

 

If you disable closed loop operation and run open loop all the time, the readings from the O2 sensors will be ignored.
You do most of the tuning in the AFR vrs Load table (LT1 edit). Fine tuning can also be achieved with the injector constant (general fueling) and injector offsets (will mainly affect idle).
A wideband and logging software are a must.

RG

 

WOT fueling is adjusted by means of the PE vrs RPM tabe.
RG

 

This is very true.

 

so if my car runs rich as hell when i first start it up. to the point where it feels like its going to shut off but doesn't this is the table i need to work with. do i need to put the desired afr ratio in the appropriate cell?

 

You'll make the changes in your MAF Calibration tables. Just remember that the car is supposed to run pretty rich on a cold start up. My car idles in the 12-13's:1 area when cold and is ~15:1 hot.

 

the thing is the car is in speed density mode because im working on getting my VE tables tuned. when the car is in open loop SD mode it idles at like 650rpm. then when it warms up it goes to the 900rpm i have set in the IAC tables.

 

Well, if you're idling a heads/cam car at 650 rpm cold, then that's why it wants to die. Stock cars idle at 650 rpm. Bring the idle up to at least 800 rpm.