This may be a stretch as to whether it's really a Maxima post, but you'll see how I relate it in a second.

The Road and Track Buyer's guide for 2003 lists the specs for a lot of cars. I was astonished to see the 350Z weighing in at 3290 lbs when the Maxima weighs 3248. WTF?

Comparable cars (I understand the difference in hard tops vs. convertibles and 4 cyl vs v6's but take a look anyway):
S2000 2809
Miata 2387
Audi TT 2921
BMW Z4 2772
350Z 3290
Maxima 3248

Does the 350Z need to go on a diet?

 

Those first few are smaller cars, and also smaller engines. The 350Z is on the G35 platform, a fullsize sedan. You could never make a fullsize sedan out of the Miata platform. The TT is 4 cyl. turbo. Get the Quatro option and you are up to Z weight, 3274.

As far as the Z4, compare prices - there's your answer.

Modern sports cars aren't too light weight, that's a common misconception. Even my buddy who owns a Z06 thought the 350Z would only weigh 2,000 lbs "like my vette." Sorry dude, your vette weighs as much as my Max.