Do the Gt40 heads found on the early Explorers, Cobras, and Gen1 Lightning have smog ports? I need to pass emissions for the county I live in. Truck in question is my sig. Thanks.

 

I've bought a set of gt40 heads for my truck my emission set up is a link coming off exhaust manifold. I would look at the things on YOUR truck and compare.

 

Yes,

My GT40's off a 93' Cobra came with smog ports on the back of each head.

 

The GT40s I took off an 96 Explorer were not drilled for AIR injection at the rear of the head. I suspect they MIGHT be drilled to utilize the type of air injection that most of this gen trucks use.

But I'm only familiar with 5.8s

 

Thanks guys. So if I get GT40 heads that do not have the air injection ports, is it unlikely I would pass emissions not running the air pump?

 

The common thought is that AIR injection is primarily to reduce emissions from dead cold. If the engine is hot, the cat will do what its supposed to do & you'll pass if the tailpipe measurement is the only important thing. Visual could be an different thing. I know I've run across threads from LONG ago detailing how folks would pass with disconnected pumps & more modern cats... But don't take any of that as gospel cause I've never had to deal with it.

 

Most modern converters don't need air injection anyway, so eliminating the air system is no prob

 

Just be aware if you remove the air injections hoses, solenoids, etc. you will fail a few of the KOER tests. There will not be a Check Engine Light but if your local emission testing includes running the KOER tests you will be failed.