What effect,, if any will wrapping my exhaust headers have on the fuel map?? If any.
I'd imagine that there would be some difference given that the area where the 02sensor will be will be arguably hotter. ( at least at idle) IMHO
Once done I'll post the results but will be interesting to see what the collective thinks before I do it.

[Edited on 8/2/10 by omega 24 v6]

i dont think wrapping the exhaust headers will make any diff on the fuel map. ive had a car in this week that i had to wrap the exhaust and got asked the same about the sensor, has your sensor got a preheat wire. iam remapping the car next week and iam gonna check this out lol.
adam

the heaters in the sensor are controlled by the ecu if the exhaust is up to temp sooner they go off sooner.

the only time you may have an issue if if you get the sensor over its recommended running temp but you will probably kill the sensor.

OK so the afr showed it as running lean?? but it was way way colder airtemps than it was setup at during the summer

The lambda senors (and cat) will work better, the ECU may make the mixture slightly leaner.


As Lambda sensor age the sensor responds much more slowly and you tend to see a very slight drift down in output voltage which makes the ECU think the engine is running slightly lean hence it adds more fuel. Getting the exhaust really hot partly compensates for this.

This is why getting the engine stonking makes getting a car with slightly high emmisions through the MOT a bit easier.

My old manifold was lagged but when my rather nice new stainless item was first installed I found I had problems, when stuck in traffic, with the fuel vaporising in the fuel rail until I lagged the manifold. It will help drop the under bonnet temperature if nothing else.