Quote:
Originally posted by OffroadX:
Right, and it pisses me off that SLR calls the upper cats the "pre" cats, since they are actually the primary ones. The non-california-emissions 2000 models only have those, not the secondary/cleanup ones that are beyond the point where the headers go.
The "secondary/cleanup cats" further down the exhaust stream are actually resonators, not "cats" at all, even on the California emissions trucks.

Removing the resonators does not impact emissions.

Removing, or even moving the catalytic convertors from their original location (with respect to heat), can cause the truck to not pass emissions.

I drove my 02' X without catalytic convertors for 8 months. All it did was illuminate the SES light a couple times. After the light was cleared, it would take a few months or more before the light comes on again. Driveability wise, there was no difference in the operation of the truck.