beginner tuner, a/f ratio question
03-16-2019, 11:47 AM
#1
Staging Lane
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beginner tuner, a/f ratio question i am preparing to tune my car for the first time. car was previously tuned with a cam, LT, full exhaust. since then i have went to a forged bottom end, 243 heads with a valve job, different cam, but still have the ls1 intake as of now. i bought a wideband and hooked it up and the car is running extremely rich all the time. right at high 10s, low 11s at idle and mostly low to mid 11 cruising. i was preparing to change my values in the main ve table, when a thought struck me. i have been wanting to upgrade intakes, and i was curious if i went with say a fast 92 or 102, would this cause the car to lean out some? it should definitely deliver more air, but will it also give more fuel? sorry if this is a dumb question, this is my first time tuning a car, and have gotten 95 percent of my knowledge about it from google and youtube videos
03-17-2019, 01:58 AM
#2
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i am preparing to tune my car for the first time. car was previously tuned with a cam, LT, full exhaust. since then i have went to a forged bottom end, 243 heads with a valve job, different cam, but still have the ls1 intake as of now. i bought a wideband and hooked it up and the car is running extremely rich all the time. right at high 10s, low 11s at idle and mostly low to mid 11 cruising. i was preparing to change my values in the main ve table, when a thought struck me. i have been wanting to upgrade intakes, and i was curious if i went with say a fast 92 or 102, would this cause the car to lean out some? it should definitely deliver more air, but will it also give more fuel? sorry if this is a dumb question, this is my first time tuning a car, and have gotten 95 percent of my knowledge about it from google and youtube videos
hopefully someone with experience chimes in.
03-17-2019, 04:44 AM
#3
Staging Lane
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I’m running a speed density tune so I’m not using the maf, it’s going off of the map sensor, that’s why I believe it would lean it out. A new intake shouldn’t change vacuum any I wouldn’t think so the tune should stay the same, but it should be getting more air
03-17-2019, 09:17 AM
#4
2. Disable LTFTs. These will skew STFTs overtime and you really don’t need them.
3. Disable PE. You want to make sure that your part throttle PE table is correct or as close to +-5 as possible.
4. Enable PE. Set enable map to 50 and delayed rpm to 0.
5. Set pedal engage to 65%.
6. Set PE AFR to 12.5 or what you desire.
When you start with PE tuning. Watch your AFR closely.
The above is a guide only and not exhaustive by any means.
I would also be careful with the spark table. Don’t run too much timing. I would stay around 24 degrees at WOT.
03-24-2019, 12:47 AM
#5
TECH Fanatic
Here's a complete guide on how to fix your problem. It's definitely tune related. PE mode should get built into your VE table, meaning that when you have it set up, the commanded fuel will change when you enter PE mode, and your log will reflect this target and AFR error percent. In essence all your PE settings will end up being built right into your VE table.