From dave

Hey cafe...it is somewhat an issue with single turbo...you will need a
cat..and then you need to find a junkyard corvette air pump because it
is
electric..and then you just hook it to the cat so it runs clean...we've
done
it several times and works well..you can also help it by loading an
"emission" map into your ecu system...whichever you use....hope this
helps..dave@KDR