Exhaust fumes in passenger compartment???? Can't figure it out?

[Green Mopar Guy]

I have a 71 Cuda that has exhaust fumes coming into the passenger compartment.  I've checked the headers, valve covers, collectors, etc. and they're all sealed properly.  It's especially bad when I accelerate--Makes driving a very cool car kind of nasty because I'm breathing so much exhaust.  I've even sealed up the trunk area going the rear seat in case the fumes were coming in from the rear.

Does anybody have insight/suggestions on this problem? 

Thanks!

[quagmire]

Where does your exhaust end?  If you have a full exhaust that goes all the way back there has to be an exhaust leak somewhere.  If it doesn't each all the way back (as in it terminates under the floor pan) that may be why you are getting fumes in. 

[bb71challenger]

Check your taillights and your trunk pan. If there is a hole the car will actually suck in the exhaust. I was in the process of changing out my taillights and was driving my car without the 70 tails in there. I could not get over how quick and how thick the exhaust fumes accumulated inside the cabin.

[Chryco Psycho]

 
 if you have ever replaced trunk pans drops wheel tubs or quarters if all the seams were not re-sealed it can draw in exhaust , even trunk seals & tailights can leak