Please Help Me Reduce Cabin Noise On Fox Body

the car is made of lots of sheet metal

what happens when you take a piece of sheet metal and tap on it? It vibrates, sometimes hurts your ears

same for solid motor mounts. The small amount of vibration from the engine is transmitted into the body of the car and you feel/hear it. People oftentimes say that it makes no difference but I am here to tell you that it DOES. May be that some don't/can't feel it over the exhaust noise.

The race car is obviously solidly mounted via front and mid plates. Always use a rubber trans mount even with solid mounts! On that car, it's about 15:1 compression, and you definitely feel the engine running particularly at lower speeds (it idles at 1400). Feel AND hear it through the body/frame/chassis.

Use some fatmat dynamat or hushmat on all of the interior, floor, doors (inside the doors and just behind the door panels), and roof. If you put it on the bottom of the roof, whenever it rains, you will certainly love the sound deadening! Can't even hear a light rain in my car.

Subframe connectors tighten up the body, helps eliminate rattles and squeaks from interior panels. Weld-in SFC's are the only way to go. Bolt-in's are mostly a waste of time/money.

hang the exhaust with rubber hangers, isolates sound/vibration from the body. Also, if you have long tube headers, put some flexible couplings beteween the headers and the rest of the exhaust. They work. If you don't have tailpipes, you need them--huge difference over dumps. Cats quiet the exhaust too, as well as knock out some of the stink.

That's just the start.....NVH is a real challenge.