In stop and go traffic I'm noticing a strong smell of exhaust in the cabin. It may be coming in during faster travel but there's more airflow so I'm not sure. I've come in from rides with a strong smell on my clothes and I can definitely feel the residue on my face.

A couple of things:

There's a tear in my shifter boot. I've read that some exhaust can come through there but in my mind there should only be exhaust coming from the rear. That will be fixed soon.

The car feels like it may be running rich. I've been using 93 octane gas and the car has a K cam and 0,040 over cylinders. I'm not an engine guy--could I be pushing out richer than usual exhaust? The carbs were recently tuned.

The trunk may have a leaky seal. I've done the $20 bill test and there are definitely some spots that aren't flush and the bill pulls out easier.

I'm actually a bit concerned about the smell. It can't be healthy even though I'm sure avoiding it completely is unlikely.

Any suggestions?

Thanks.