tw8715

iTrader: (14)

Are these springs no good on the 07 revised struts? The drop numbers look real good but the rear seems like its made for the 04 struts.

Any input? I like how the rear drops a little more so the car evens out

stuartc323

No drop springs are good on any OEM shock, you need to get a shock that can handle that.

Z-Crazy

Does not look like they were revised for 07 Z.

Seems like you have done some homework already.

Technical point of view:
If you keep OEM 07 shocks and compare only the springs:

Hotchkis - .6"/.8" drop
Spring Rate - 340/330 Lbs

03 Springs - huge wheel gap
Spring Rate - 314/342 Lbs

07 Springs - huge wheel gap
Spring Rate - 314/427 Lbs

Front: The difference in numbers for front springs do not seem too shabby, since both springs are linear, Hotchkis are slightly stiffer but it may not make a huge difference.

Rear: This difference is almost 100 Lbs. To give you the best idea, 350z sits lower in the front and higher in the rear, this helps handing and when the car is under load the rear squats down a bit and front raises up. With the Hotchkis springs being softer in the back, it may create a little instability in the rear under high load, resulting in squatting up and down, eventually it will stop squatting as the load stabilize.

I am not sure at what speeds this effect can be replicated. i hope someone with these springs shares more about the speeds.This squatting will be noticeable only if you immediately drive any Z with revised suspension.

I tracked 03 Z with Hotchkis springs and 07 Z back to back, and the squatting was noticeable in 03 Z.

But the difference isn't the end of the world and I didn't mind it too much.

These are some mild technicalities that an average Joe may not notice.
(Mean no disrespect to you if your name is Joe, yes I have to mention this because a guy named Joe got offended once on another forum)

I think any drop is better than the huge OEM wheel gap, whether how you do it, is totally up to you.