Planning a complete exhaust system overhaul on a 2001... Time for... fun?

[casm]

Jeep was originally sold in Michigan. It does have the heat wrap insulation inbetween the intake runners.

Same here on both counts - mine made it from Upper Michigan to Oklahoma to Los Angeles. Finding a Federal-emissions vehicle in CA was one of the big deal-sealers on buying it.

FWIW, the heat shield (which I seem to recall Jeep referred to as a 'debris shield') was part of a TSB intended to combat heat soak. I've run with it both on and off and have never noticed an appreciable difference.

My '01 parts catalog shows the availability of a straight pipe assembly that replaces the pre-cats. However, it is marked as being intended for the euro market (which I assume was all diesel motors at that point?) and for countries in which leaded fuel was still in use - probably south america, I'm not sure where leaded fuel was still widely used in 01.

The EU market was country-by-country - Ireland, for example, almost exclusively took diesel van models due to punitive taxation on large-displacement engines as well as tax breaks for commercial vehicles, which was the category the vans fell into. In the UK (where motor tax was flat-rate at the time), both diesels and gas models were sold, mostly in the 'regular' passenger configuration seen in North America.

As for leaded fuel, both Ireland and the UK were phasing it out in the early-/mid- '90s, though you could get it relatively widely until a few years ago. I forget the exact year we had the catalytic converter mandate, but 1993 is sticking in my head, and I seem to recall that both countries required them at the same time. The phase-in was definitely gradual - Austria (IIRC) had adopted unleaded fuel without a catalytic converter requirement somewhere around 1988 but went to cats in the early '90s, and the ex-Eastern Bloc countries phased in as they joined the EU.

One odd thing this brings up in relation to XJs: they were officially sold in Continental Europe (mainly Germany and France) pretty much from new, but not in Ireland or the UK until 1993/4 or so. This means that there may be models from '84-'92 or so that are effectively emissions-free in LHD, but all RHD gas models officially sold in the Irish and UK markets should have similar emissions gear to US models, if not the same; ditto '93 or so on up LHD EU models.

* anyone know what S/C stands for, or have a good guess? NAB means leaded fuel, per the table at the top of the page in the catalog.

I'm looking at the catalogue now, and notice that the term 'S/C' also throws up NAC, NAS, and ENC in close proximity to it. I suspect the 'NA' part of 'NA*' means 'naturally aspirated', since 'ENC' is used in relation to a turbo gasket, which would suggest diesel. Not 100% certain on that, though.

Oh, wait. There's a reference to "S/C Z5B" on p.325. "Z5B" looks like a code from the option sheet under the heading of, "LABEL, Emission U.S. 50 States with S/C Z5B U.S. 50 States with S/C Z1A and Z1B...". I'm guessing S/C is shorthand for a build option from this context, but that could well be wrong.