Will removing the cat on an '83 SC effect my emissions all that much.

chrisp · 11-08-2003, 04:29 PM

I am planning the SSI, 2 in one out upgrade and I am wondering if I should worry about emissions. I am not sure of the emissions numbers in Rhode Island but I suspect it's similar to CT or MA. Anyone have any experience with this?

The car has yet to be tested in RI.

AFJuvat · 11-08-2003, 05:36 PM

I don't know what the standards for RI are, but if you remove your cat you will most definately fail.

AFJuvat

singpilot · 11-08-2003, 06:03 PM

I happened to have my test pipe installed when my Co2 was set recently after a tuneup. The tech said the readings (NoX and Co2) indicated that my cat was weak, that another year or two, and I would be replacing it to pass a smog test.

I didn't have the heart to tell him my cat was in a box (temporarily) in Nevada.

A properly tuned engine gets pretty close to passing.

Jim Garfield · 08:44 AM

Chris,
I have a 3.2 engine - B&B headers and muffler w/no cat. The last time I had the rolling emissions test done a year and a half ago the car passed with flying colors.

I had the test done at Northup's Imports on Main St. in Wakefield. Bill Northup does the tests and he's fond of aircooled cars, he's just begining to restore a seriously clapped out 912 with his son.

Interestingly I was told by DMV that from now on my semiannual inspection will only include safety items and not emissions as the tub is a '78 and cars more than 25 yrs. old don't have to be tested in RI.

edit: BTW I wasn't implying that there was anything "funny" going on with the testing because he likes aircooled cars...the machine just spits out the numbers. I was just happy to find out that contrary to some opinion, it is possible to pass the emission test with a well tuned car and no cat.

Joe Bob · Joe Bob's Garage

I passed on my 83 euro 3.0 w/o cat with SSIs but needed the air pump to pass CA emissions.

chrisp · 11-09-2003, 12:50 PM

Thanks guys....especially Jim. Nothing like local input and a recommendation as to where to take it.

Jim, let me also ask from you, what do they look for in the safety inspection? My car is in fine road condition; all lights, wipers, etc work. The only things that I am in the middle of are reconnecting the horn after I installed a Carrera front cooler and I am in need of a windshield washer system.

Are those items looked at in the inspection?

Jim Garfield · 11-09-2003, 01:30 PM

Chris,
The horn will definitely be checked, I'm not sure about the washer system though. The safety inspection is pretty basic...lights, tires, brakes, etc.

Northup's # is 783 6500, I would give them a call to see what is checked.

Good luck, post here if it passes the emission without the cat.

chrisp · 11-09-2003, 05:29 PM

Thanks Jim.

I'll give them a call and see what the inspection is like. My other two cars are pretty new so they rolled in and rolled out. This one will involve more I am sure.

I am thinking of getting the inspection next week with current parts (wire up some sort of horn) and tune and then switch to the SSI's and muffler sometime this winter. Then I won't need to worry until 2005.

Jim Garfield · 11-10-2003, 09:02 AM

Chris,
That's probably the safest route to go, that way you don't end up having to remove anything and retest if it did fail. I'm pretty sure that the tests only have to be done every two years.

Are you still planning to rebuild your engine this winter? Let me know if you need any help with your engine drop, I'm just across the bridges in Wakefield.

Jadams1 · Jadams1's Garage

Wow, so many RI'ers posting in one thread! I just got my 80 SC inspected last week and I don't have a CAT, I have a pre-muffler. I failed the first test on % CO at idle, and passed the second time after I leaned out the fuel mixture and retarded the timing a little. My car did not go on the rollers, they did the two idle speed test (idle and at 2,500 rpms). In RI if the car is over 25 years old, it doesn't have to pass emissions, just safety. The sticker is good for two years and cost $47.

The limit on %CO for a 79 911SC is 2.5%, I measured 3.6% on first test, 0.09% on the second test. My car really ran like crap at those lean conditions. As soon as the test was done, I richened up the fuel mixture back were it was. My 80SC is registered as a 79 but that's another story in itself.

Jim, the state has lowered the emission limits a tad from two years ago, but your 78 won't need to be tested.

Chris, good luck on your test. When is the last time you replaced you O2 sensor?

DG624 · 11-10-2003, 04:18 PM

Why would removing the CAT affect the CO2? I thought it had an effect on the SO2 and NOX. CO2 should be whether the engine is running efficiently. Does the state (any state) test for SO2 or NOX? I have never been tested and am interested in changing the exhaust also.