EMISSION FAMILY CODE:
NOTE: enfn means ENGINE FAMILY NAME
In order to properly determine which catalytic converter to use on certain applications, it is necessary to determine the type of catalytic converter originally used on the vehicle. This information (required by the EPA) is included on the vehicle emission control information label located in the engine compartment in a visible position on the hood underside, shock tower, radiator support, fan shroud or firewall. (An example is shown below.)
Two-Way (Oxidation) = OC or COC
Three-Way (Oxidation Reduction) = TWC or ORC
Three-Way + Air (3-Way Plus Oxidation) = TWC/OC or ORC/OC

click to enlarge
| UNIVERSAL COVERAGE CHART |
| SERIES |
FUNCTION |
EPA FEDERAL |
CARB CA* |
| ENGINE LIMIT |
TEST WEIGHT |
ENGINE SIZE |
TEST WEIGHT |
| 50000 |
Inline Pre-Conv (1)
Y-Pipe Pre-Conv (2) |
180 CID/3.0L
360 CID/5.9L |
4500 lbs.
4500 lbs. |
180 CID/3.0L
360 CID/5.9L |
4500 lbs.
4500 lbs. |
| 53000 |
2-Way, 3-Way |
256 CID/4.2L |
4250 lbs. |
244 CID/4.0L |
4250 lbs. |
| 53100 |
3-Way |
256 CID/4.2L |
4250 lbs. |
244 CID/4.0L |
4250 lbs. |
| 54000 |
3-Way |
322 CID/5.2L |
4500 lbs. |
307 CID/5.0L |
4500 lbs. |
| 91000 |
3-Way |
256 CID/4.2L |
4500 lbs. |
244 CID/4.0L |
4500 lbs. |
| 93500 |
2-Way, |
477 CID/7.8L |
7000 lbs. |
460 CID/7.5L |
7000 lbs. |
| 3-Way |
477 CID/7.8L |
7000 lbs. |
454 CID/7.4L |
7000 lbs. |
| 3-Way+Air |
378 CID/6.2L |
7000 lbs. |
368 CID/6.1L |
7000 lbs. |
| Frt-Rear 3-Way+Air |
368 CID/6.1L |
7000 lbs. |
351 CID/5.8L |
7000 lbs. |
| Main-Pre 3-Way |
239 CID/5.2L |
5500 lbs. |
N/A |
N/A |
| Main-Pre 3-Way + Air |
318 CID/4.2L |
4500 lbs. |
N/A |
N/A |
| 94000 |
2-Way, 3-Way, 3-Way+Air |
378 CID/6.2L |
6000 lbs. |
360 CID/5.9L |
6000 lbs. |
| 94100 |
2-Way, 3-Way, 3-Way+Air |
378 CID/6.2L |
6000 lbs. |
360 CID/5.9L |
6000 lbs. |
| 94200 |
2-Way, 3-Way, 3-Way+Air |
378 CID/6.2L |
6000 lbs. |
360 CID/5.9L |
6000 lbs. |
| 94400 |
2-Way, 3-Way, 3-Way+Air |
378 CID/6.2L |
6000 lbs. |
360 CID/5.9L |
6000 lbs. |
| 95000 |
3-Way+Air |
378 CID/6.2L |
5500 lbs. |
360 CID/5.9L |
5500 lbs. |
| 95500 |
3-Way |
460 CID/7.5L |
13,000 lbs. |
454 CID/7.4L |
13,000 lbs. |
|