I live in central IL and we do not have emission testing here. I am looking into getting some Jet-Hot LT's but am not sure what exactly I should get. Is there any HP loss when buying the ones that will pass emissions? What is different about the ones that will pass and the ones that won't?

Thanks!

J

 

Normally headers designed to meet emissions are shorty or mid length types. These headers are usually down on power a bit compared to longtubes. Longtubes and cats on a LT1 car require some creative packaging to make it all fit.

 

LT's, by definition can NOT pass emissions, because they relocate the cat(s). The tailpipe emissions will be fine, but they will not pass a "visual" if the inspector knows what he is doing (questionable). Often, they do not include the required emissions connections, like O2 sensors, AIR ports or EGR connection.

You absolutely have to have the O2 sensor bungs on the LT's... the O2 are required for the PCM to operate and produce decent fuel mileage and the correct A/F ratios.

The EGR or AIR connections are not required. There is absolutely no performance difference, whether you have or don't have AIR or EGR. Neither of these systems operates at WOT. AIR runs for a couple minutes at startup to heat the cat(s). EGR recycles exhaust gas to the intake manifold to reduce combustion chamber temperatures when you are lugging the engine under certain low/moderate RPM conditions. It will actually reduce the probablity of detonation (knock) under these conditions, but I serioulsy doubt a knowledgeable enthusiast is going to lug the engine frequently in the wrong gear.

So.. comes down to whether you need to pass a "visual" inspection, whether you need to pass a "rolling" emissions test that measures NOx, and whether you just want your car to produce limited emissions.

 

No benifits at all !!. I dont even have a cat on my car but I do have MAC mid-length headers. The reason I didnt get LT's was because you or a cop can see the LT's underneath the car. The sound and power are noticiable hahahaha even a retarded smog inspector would notice LT's !!