Is this too lean of an A/F at idle?

[S/CCobra03]

I just installed a set of LT headers on my 03 a few weeks ago. I've noticed that the car is now idling at 15.2-16:1. It would always idle around 14.7 before the LT's. The WOT A/F has not changed. So will I have to get a new tune in order to fix my lean condition at idle? I thought custom tuning would only change the A/F under WOT.

 

[gmynko]

I don't think so - ask an expert

 

[p3pete]

I just installed a set of LT headers on my 03 a few weeks ago. I've noticed that the car is now idling at 15.2-16:1. It would always idle around 14.7 before the LT's. The WOT A/F has not changed. So will I have to get a new tune in order to fix my lean condition at idle? I thought custom tuning would only change the A/F under WOT.

I'm not an expert, but what I've been told is that under part throttle/idle the computer tries to go to stoichiometric which is 14.7:1. Here's a link to some info I found:

http://home.earthlink.net/~graham1/MyToyotaPrius/SideBars/Stoichiometric.htm

I'm not sure why it would idle a touch higher, but my bet is that it isn't too big an issue. Here's where an experienced tuner can step in and answer that question...

Good luck!

 

[racebronco2]

my cobra at idle the a/f ratio is between 14.3 -15.3, same as when i am crusing

 

[Brad]

I just installed a set of LT headers on my 03 a few weeks ago. I've noticed that the car is now idling at 15.2-16:1. It would always idle around 14.7 before the LT's. The WOT A/F has not changed. So will I have to get a new tune in order to fix my lean condition at idle? I thought custom tuning would only change the A/F under WOT.

Not to hijack but how'd you, "self," port your blower? Got pics? I ported mine too. Any dyno results?

 

[bender460]

o2 sensor transport delay in your tune?

 

[S/CCobra03]

Not to hijack but how'd you, "self," port your blower? Got pics? I ported mine too. Any dyno results?

I have before and after pictures that I will try and PM you tonight. I still haven't made it to the dyno yet though. However, my will run door-to-door with a Steg. stage three ported car. I know this because one of my friends has one.