I have the same exhaust.

Firstly it is very important that your car has the revised calibration from Omex in the ECU. Without that the fuel air ratio will not be correct. There were a lot of complaints from owners before Omex, in conjunction with Williams, developed a new calibration.

You may also like to read my post on the catalytic convertor and how I resolved a similar problem after about 50,000 km on the original cat. I came to the conclusion that the original cat was inadequate and I am very happy with the replacement.

http://www.talkmorgan.com/ubbthreads.php/ubb/showflat/Number/500409/

Peter

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