Do I need to remap?

[Joshua1902]

Hi, I'm looking at putting a 4-2-1 manifold and a full stainless straight through which has a decat, do I need to remap my car after this or will it be fine to run?

[suckerface]

You'll just need to reset your ECU. Remove the neg battery terminal for 5-10 minutes, then replace, and the ECU will re-learn the fuel trims to level off your idle (about 5-10 minutes as well). It may take up to a day or two to really level off as it finishes the fine tuning.

[Joshua1902]

Do I need the engine started when I remove the negative terminal, is this the only thing I will need to do?

[suckerface]

No, engine off, remove neg terminal, install header, replace neg terminal, start car. No idea what sort of havoc you would create removing the neg terminal when the car is on.

[Joshua1902]

Thanks, ill let the garage know before they swap them over