Simple (?) LS1 Edit question... adjusting A/F
Thread Starter
TECH Senior Member
Joined: Nov 2001
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From: Lake Zurich, IL
Simple (?) LS1 Edit question... adjusting A/F OK... what tables should I start playing with?
Right now I have the mods in my sig... and the car seems to be running pig rich (w/cats on you could smell fuel, now /ORPs it's pretty bad heh)
Just baseline I used my MAFT. I had to adjust it +10% richer base in order to zero out my LTRIMS.
However, while the computer thinks I'm running fine now... I (of course after having made it richer base) smell fuel...
I know the car's running richer than it should because I just swapped out my 02s after 1000 miles (1000 miles since all internal engine mods + headers) and the passenger side was black (having been in the car for 40,000 miles previous to this they had not been black)...
So is there a way for me to adjust the PCM so that it thinks 10% leaner than now is normal and it doesn't need to add fuel? (meaning, I want to pull 10% of the fuel, but don't want the PCM to compensate for this...)
Thanks
Right now I have the mods in my sig... and the car seems to be running pig rich (w/cats on you could smell fuel, now /ORPs it's pretty bad heh)
Just baseline I used my MAFT. I had to adjust it +10% richer base in order to zero out my LTRIMS.
However, while the computer thinks I'm running fine now... I (of course after having made it richer base) smell fuel...
I know the car's running richer than it should because I just swapped out my 02s after 1000 miles (1000 miles since all internal engine mods + headers) and the passenger side was black (having been in the car for 40,000 miles previous to this they had not been black)...
So is there a way for me to adjust the PCM so that it thinks 10% leaner than now is normal and it doesn't need to add fuel? (meaning, I want to pull 10% of the fuel, but don't want the PCM to compensate for this...)
Thanks
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From: Hot Rainy Humid +2000 DA South Florida
Re: Simple (?) LS1 Edit question... adjusting A/F Definately get rid of the MAFT and do all of your tuning in LS1Edit.
You are also going to need something like ATAP or EFILive etc to log data.
This is a rule of thumb I go by when tuning..
Make sure the car fires right up. Make it idle nice and smooth, and you get good IAC's 30-50 etc, if you hit the throttle the MAF flow should increase etc. Cruise around monitor your LTFT's. you want them at 0 to a little negative -3 to -5 etc. Make sure you have no surging when stopping etc. For WOT check your timing and your A/F, watch your O2 readings. If everything is looking good then tune your A/F with the PE vs RPM. If you lower the table cells it will lean your A/F. For example if you are at 11.3 A/F and you lower by like 98% it will change the A/F to like 11.6 And if you raise the table it will richen you up.
Definately try to do your A/F tuning on a Wide Band Dyno. Atap will give you close A/F reading but you dont wanna go too lean based on those readings.
Good Luck.
Thread Starter
TECH Senior Member
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
Re: Simple (?) LS1 Edit question... adjusting A/F ok cool. I'll be having the car dyno tuned at FLP in a few weeks, but want to get a good basic tune in the car for drag racing this weekend (finally getting some numbers on it)
So the PE vs. RPM table only affects fuel at WOT right?
Or does it do part throttle also? Right now I'm mostly concerned about part throttle driving as I seem to be dumping too much fuel at part throttle and it's fuxoring my O2 sensors...
Before changing the O2 sensors out, Drivers side was zeroed out (LTFT) but passenger side was like 15%... upon inspection passenger side was the one that was really bad, all carboned up.
I'll have to atap my car again this week (I'll prolly drive it to work tomorrow)... last time I checked my IACs were at 0 cause my TPS was reading 5%... (had my TB ported when I did my buildup)...
So basically I should log:
Front O2s, LTFT both sides, Fuel Cell, IAC, TPS, MAF Flow, IAT
How do I calculate the A/F w/those values?
Thanks a ton!
So the PE vs. RPM table only affects fuel at WOT right?
Or does it do part throttle also? Right now I'm mostly concerned about part throttle driving as I seem to be dumping too much fuel at part throttle and it's fuxoring my O2 sensors...
Before changing the O2 sensors out, Drivers side was zeroed out (LTFT) but passenger side was like 15%... upon inspection passenger side was the one that was really bad, all carboned up.
I'll have to atap my car again this week (I'll prolly drive it to work tomorrow)... last time I checked my IACs were at 0 cause my TPS was reading 5%... (had my TB ported when I did my buildup)...
So basically I should log:
Front O2s, LTFT both sides, Fuel Cell, IAC, TPS, MAF Flow, IAT
How do I calculate the A/F w/those values?
Thanks a ton!
Re: Simple (?) LS1 Edit question... adjusting A/F Before changing the O2 sensors out, Drivers side was zeroed out (LTFT) but passenger side was like 15%... upon inspection passenger side was the one that was really bad, all carboned up.
JR
Thread Starter
TECH Senior Member
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
Re: Simple (?) LS1 Edit question... adjusting A/F Before changing the O2 sensors out, Drivers side was zeroed out (LTFT) but passenger side was like 15%... upon inspection passenger side was the one that was really bad, all carboned up.
JR
Before I did have an exhaust leak right where the header bolted to the Cat (broke the clamp installing)... I had about 800 miles on it like this before I dropped it off for a new transmission...
