Cat removal on my V8

[ibandre]

I think I read somewhere, that after replacing the stock ECU with the Red race ECU, it will be ok to remove the cats without screwing up the lambdasensors. With the stock ecu still in the car, the lambdasensors will register a fault in the A/F mix, but the red race ecu will overlook this problem. Is this correct?? I am pretty sure I read this on lotus esprit world somewhere.

[actwon]

I think I read somewhere, that after replacing the stock ECU with the Red race ECU, it will be ok to remove the cats without screwing up the lambdasensors. With the stock ecu still in the car, the lambdasensors will register a fault in the A/F mix, but the red race ecu will overlook this problem. Is this correct?? I am pretty sure I read this on lotus esprit world somewhere.

I am not sure about Lotus's RED ECU. I know that Johan's ECU ignores the Lambda sensors, so it can be taken out.

[ibandre]

I bought the one from motoconcept in germany. It`s supposed to be similar to the red race ECU from lotus.

Maybe I should just leave it be, and keep them in if I`m not sure.

[peter_england99]

I'd verify with Markus before making a descision.

Regards,

Peter.

[ibandre]

Markus? On this forum?

[Zhastaph]

I don't know what spec Esprit you get in Norway but as far as I'm aware it's only the US cars that care whether the cats are there or not. Certainly the UK cars don't care.

[peter_england99]

I'm sure he has posted here. However, it's probably best to go via his www.pukesprit.de web site.

Regards,

Peter.

Markus? On this forum?

[Paula&Marcus]

Hi All,

The V8 has 4 lambda sensors. 2 pre cat sensors and 2 post cat sensors. The 2 pre cat sensors are the important ones who are registering the A:F and the ECU is doing its fuelling calculations based upon the reading of these 2 pre cat sensors.

The 2 post cat sensors are ONLY there for emmission control purposes. This means if there is a cat malfunction the post cat sensor will detect it and will cause the CEL-light go ON.

With the Red ECU the reading of the post cat sensors is ignored once the engine is running. However when you switch ON the ignition the ECU will look out for the post cat sensors if they are just there !

You see its a bit different to that what you have heard ....

Conclusion: Keep ALL sensors in place and donot worry about the cats if you have the Red ECU installed. I personally recommend high flow metal cats. These will improve the flow dramatically and will still do the catalytic effect.

Cheers

Marcus

I think I read somewhere, that after replacing the stock ECU with the Red race ECU, it will be ok to remove the cats without screwing up the lambdasensors. With the stock ecu still in the car, the lambdasensors will register a fault in the A/F mix, but the red race ecu will overlook this problem. Is this correct?? I am pretty sure I read this on lotus esprit world somewhere.

Edited March 2, 2007 by Paula&Marcus

[MufflerMan]

Marcus is correct. In fact you don't need the red ecu to remove the cats, I did it before I even had the red ecu. The only thing that will happen is a CEL. The car does not go into the "limp mode" as rumor may have it.