Turbo6Smackdown
Well-Known Member
- Joined
- Dec 31, 2005
I was decoding my regal gs's rpo tag, and noticed the NB6 rpo. It says. "EMISSION SYSTEM, CALIFORNIA, TIER 1"
Now, what exactly does this mean? Is this in a separate class all it's own, because there's non cali emissions compliant cars? So does this mean there's a different t-stat/cat converter/tune in the pcm?
How do these cars differ from non "NB6" cars?
The reason I ask this, is because I get 2 inklings. First, from what I read elsewhere, my '98 GS should have a little more top end than it does. Secondly, I get a bit of knock retard, even after I replaced the plugs to 1 heat range cooler, wires, coils, checked the control module, free'd up the exhaust a little, and put a better tune in the pcm. And this is all with the stock pulley.
So far, I can't find any vac leaks, and my gas and fuel pressure is good. The only other thing I can think of, is a restriction in the exhaust system somewhere, causing boost stacking, and heating. The only thing that could be, is my cat. The car's an arizona car, and only had 70,000 on the clock when I bought it in may.
Could this car have a different cat?
Now, what exactly does this mean? Is this in a separate class all it's own, because there's non cali emissions compliant cars? So does this mean there's a different t-stat/cat converter/tune in the pcm?
How do these cars differ from non "NB6" cars?
The reason I ask this, is because I get 2 inklings. First, from what I read elsewhere, my '98 GS should have a little more top end than it does. Secondly, I get a bit of knock retard, even after I replaced the plugs to 1 heat range cooler, wires, coils, checked the control module, free'd up the exhaust a little, and put a better tune in the pcm. And this is all with the stock pulley.
So far, I can't find any vac leaks, and my gas and fuel pressure is good. The only other thing I can think of, is a restriction in the exhaust system somewhere, causing boost stacking, and heating. The only thing that could be, is my cat. The car's an arizona car, and only had 70,000 on the clock when I bought it in may.
Could this car have a different cat?
