Hey I am purchasing the eibach pro-kit springs for my 2004 g35 coupe. I need help on knowing if I have to purchase struts or shocks? I just need to drop the car, I dont really feel like changing the stock shocks or struts right now. please advise. thank you.

 

Nissan oem shocks generally last 4 year or 60k [before reaching the 1/2 stiffness point on rebound] with stock springs.
Progressive rear springs can be up to 200% stiffer at 2" compression so expect the rear to wear very fast depending on how the roads exercise the springs.
Most drivers are insensitive of how shocks work and feel, so they wait way to long after they are worn out to change them.

Springs have very little to do with real handling, as tires are 90% and springs might contribute 5% at best. They do change the feel for inexperienced drivers.

But mostly they just add to manufacturers income.

I've used Eibach's since 1993 on my Q45 [323K], but that is a special case since the rear oem's are only 123 pounds/inch wheel rate on a 4000 lb vehicle and the new 120>220 rate avoids the necessity of a larger than 20mm rear sway bar maintaining near oem traction levels except in > 0.75G turns thanks to rear VLSD.

 

he has 90K miles on his OEM suspension and is looking to get the eibach pro kit, as in just the springs. He was told that the springs have an inch drop all around so it wont put too much of a stress on the stock struts but with 90K miles on it, what would you guys advise? And also is the claim of these pro kit springs on OEM struts true? Anybody with a pair on their cars wanna comment on this?

 

What difference on which car does it make. Springs are springs and lowering 1" requires the same INCREMENTAL change in stiffness. The weight doesn't matter as the road clearance [static ride height] are almost exactly equal.

 

The stock shocks/struts will work ok with the Eibachs but they'll wear out quicker. At 90K, it's probably a good idea to get some sport shocks to go with the springs but not required. That is all.