Hi... I've got a AUS ITR with K&N replacement filter and JDM 4-1 header with stock cat (stock exhaust too, coz I don't want it to be loud).
Last week, I changed my cat to a carsound 3 inch and it made a lot of difference on butt dyno (when I change the stock 4-2-1 AUS to JDM 4-1, both with the stock cat, I could not feel anything). However due to some problem with the cat (rattling, etc) the exhaust shop refunded my money and put my stock cat back on.

I found a knowledgeable tuner who sells carsound cat with a better price, so I decided to get the cat fitted and have my VAFC tuned on the same day.

Wouldn't the ECU need to re-adjust to the new cat, and if I get my VAFC tuned just after the cat is installed, would the ECU setting change after a few days?

Put it this way... The last time I resetted the ECU, the car is using stock cat. Now the car has a hi-flow cat (but the ECU hasn't adjusted to the new cat) and the tuner is going to play around with the air/flow.
Now..... If reset the ECU in a few days after tuning, the ECU would re-adjust to the new cat, right? so that means the VAFC setting would not be correct anymore????

IF the tuner resets the ECU before tuning, will it work, coz the ECU take quite a long time to re-adjust, rite?
from my experience, it takes about 1 full tank of petrol before the ECU re-adjust, and during that time my fuel consumption will be worse and the car will be slower. If the car is tuned during this time, what's gonna happen?

This might sound silly but I'm curious.....
What's ur opinion?
btw does anyone know how the ECU re-adjusts when u reset it?
and do they reset the ECU before tuning?
sorry guys... this is the first time I'm getting my car tuned... LOL

Thanks guyz....

 

bump....

helloooooooooo

can anyone help?

 

what type of ecu program are you using? ecu does not self-tune, theres also no need to reset ecu (people take this to extreme with all kind of retuals), it adjusts for startup as far as i know, but not wot runs.

 

so what u r saying is that the ECU never adjusts the wot map setting?

oh cool thanksss

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boszyen &raquo;</TD></TR><TR><TD CLASS="quote">so what u r saying is that the ECU never adjusts the wot map setting?

</TD></TR></TABLE>

Correct.

The ECU runs on open loop during warmup and WOT/aggressive driving, which is all one map.