Well I thought I'd post this for the benefit of anyone having similar issues with the CA ( or other states for that matter) Smog Nazis. My original CA 78 FJ40 has always struggled to pass CA tests and I live in a county that requires the biennial 'test-only' check.
Every two years I have had to deal with the various smog check stations with techs that are younger than my truck and have to be shown how to open the hood. To make the story short I
went out and had a test done and my 40 failed one of the tests for CO. I had the carb rebuilt for the last check two years ago, and it just barely passed then, so since the truck runs just great as is and everything is to spec, I decided to have a catalytic
converter put on it, rather than to deal with unnecessary diagnostics and repairs by folks that have no familiarity with the vehicle. For about $200.00 and some change I put a cat on, and did so with flanged mounting, so that if necessary, it can be removed and replaced with a straigt pipe, should heat or performance be a problem. Thus far, it seems to have made no change to performance and heat does not seem to be a problem, but I'll have to wait until we have some 100+ days to make that call. Here's my numbers before and after the cat. The numbers with the cat compare with my late model vehicles and the cat should solve the problem for many years to come!
Test results before the cat…
.......... HC ............. CO% .............. NO
.......... max avg meas max avg meas max avg meas
15 mph … 196 52 33 1.59 .024 2.43 1507 553 207
25 mph … 161 44 21 1.39 .021 1.38 1367 474 171
After the cat was installed…..
15 mph … 196 52 8 1.59 .024 0.13 1507 553 89
25 mph … 161 44 6 1.39 .021 0.23 1367 474 85
The change in the numbers just seem amazing to me!! I would have never guessed they would be so good. About 10% of what's permissable!!
Another side benefit is that it runs a bit quieter, but still sounds good. I have a set of Downey headers, 2.5" pipe, and a Flowmaster muffler on the truck. Some pics of the new cat
below...
Every two years I have had to deal with the various smog check stations with techs that are younger than my truck and have to be shown how to open the hood. To make the story short I
went out and had a test done and my 40 failed one of the tests for CO. I had the carb rebuilt for the last check two years ago, and it just barely passed then, so since the truck runs just great as is and everything is to spec, I decided to have a catalytic
converter put on it, rather than to deal with unnecessary diagnostics and repairs by folks that have no familiarity with the vehicle. For about $200.00 and some change I put a cat on, and did so with flanged mounting, so that if necessary, it can be removed and replaced with a straigt pipe, should heat or performance be a problem. Thus far, it seems to have made no change to performance and heat does not seem to be a problem, but I'll have to wait until we have some 100+ days to make that call. Here's my numbers before and after the cat. The numbers with the cat compare with my late model vehicles and the cat should solve the problem for many years to come!
Test results before the cat…
.......... HC ............. CO% .............. NO
.......... max avg meas max avg meas max avg meas
15 mph … 196 52 33 1.59 .024 2.43 1507 553 207
25 mph … 161 44 21 1.39 .021 1.38 1367 474 171
After the cat was installed…..
15 mph … 196 52 8 1.59 .024 0.13 1507 553 89
25 mph … 161 44 6 1.39 .021 0.23 1367 474 85
The change in the numbers just seem amazing to me!! I would have never guessed they would be so good. About 10% of what's permissable!!
Another side benefit is that it runs a bit quieter, but still sounds good. I have a set of Downey headers, 2.5" pipe, and a Flowmaster muffler on the truck. Some pics of the new cat
below...
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