Well, after looking at my wideband since December, I finally put it in. First time out I hooked the battery up and let the engine warm up and the first wot it said 13.1, uh that was easy. Of course after 50 miles its down in the low 12's and I even saw a high 11 at 5800 rpm. Yea its a little rich, but with E10 is it really that bad. The LC-1 shows stoich at about 13.8 but Im still set at 14.681. What are you guys commanding for AFR? I got Friday off, so it will be time to play.

 

Do you have a tune? Is your truck FI? If not, something is wrong. When I was running closed loop, mine commanded 14.681, and the wide band showed 14.7 +,- at cruise. Of course at WOT, I am commanding 11.5:1, and getting something in that area.

 

The LC-1 shows lamda and in Minnesota we have ten percent ethanol (E10). My AFR idles at around 14.6 but the true stoich of E10 is 13.8 which it does read on the way to PE. I am NA with LT's, exhaust, no egr, ory, and ported tb. Am i right that LT's without a tune will make it run rich? I have HPT and have been waiting on the wideband to do wot tuning. Ive done ltft's and have set pe to 1.199 which is a little lower than stock. I got the values from Chevy Racers thread when he first got HPT. I haven't logged with the wideband and have just observed it while driving. I have the XD-16 gauge so its pretty easy to follow the ratio. When it hit 13.1 this was after the battery had been unplugged for about 8 hours. I will be switching to E85 (I have the marine injectors ready to go in) but wanted to get a base tune down so if I can switch it if there is no E85 available. I appreciate the response.

 

Our gas is 10% corn liquor too. I never knew that 14.7 is lean with "gasohol", but I am just a caveman when it comes to tuning.

 

Well I guess it doesn't matter then. I never thought about it either until it showed up on the gauge. 100% ethanol stoich is 7.87 so I guess there would be math and stuff to figure out any % in between but thats why I bought the LC-1. 15% richer than stoich is what you want to command. I still got a lot to learn about HPT but it is slowly sinking in.

 

O2's don't know AFR, they only know lamda and lamda for gas, E10, and E85 is 1. So unless you reprogram the WB (cuz it's preprogrammed for gas) for the different fuel, it will always show 14.7 for 1 lamda no mater what fuel is in it.

 

Thats not how the LC-1 works. The gauge shows red for stoich, orange for lean, and blue for rich. When the gauge is at 13.8 it shows red. I know what your saying about the widebands reading at 1 but the LC-1s read from 0v to 5v for afr's from 7.35 to 22.39. It shows the mixture as afr and shows stoich when you hit it. Its always at the orange right now. When its warming its rich and does hit the red at 13.8. I can post a video if you want to see it. Never tried posting a vid though so it might take a while.

 

Have you reprogrammed the LC-1? I know how they work, I have used them before. Stock programing, 2.5v will read stoich, no mater what the fuel. Have you done a fresh air cal recently, so you know it's calibrated correctly?

 

I haven't done any tuning. I installed it Sunday night and did the heater than the freeair calibration. We have E10 so thats what it reads. I have the XD-16 gauge and when it starts up it reads in the 12's at blue. As it warms the gauge goes red when it reads 13.7 and 13.8. Once the engine is warm it shows orange and reads at 14.7 which is lean for E10. I haven't even hooked it up to the laptop yet. Stoich is set to 14.681 in my os. I switched to the bosch vette rear sensors because I had the low heater sensor (p0135) error. I have read about all the problems people have had with the LC-1 so maybe mines screwed too. Eventually the ltft would compensate for the E10, correct? It takes about 100 miles to change and I'm still around 70 miles.

 

E10 is all you can get in Phoenix too. My WB shows 14.7 for stoich cuz that's what its programed to show for it even though stoich might actually be 13.8 ( and motor is actauly running at 13.8). It doesn't know the difference unless you tell it. It thinks you are calculating stoich for gas. LTFT will trim it to stoich for the fuel being used. Doesn't mean that what its running at, that just what its showing. If your LC-1 is factory programed, then it should show 14.7 for stoich, NO MATER what fuel is in it (gas-E10-E85) unless you reprogram it to tell you that stoich is actually 13.8. Then it will tell you that stoich is 13.8 instead of 14.7. Make since?