Quote:
Originally Posted by SINISTER
Why is the rear spring rates stiffer on our cars?
Nismo Spring Rates:
F - 8.6kgf/mm (480lbs/inch)
R - 9.3kgf/mm (520lbs/inch)
Then when looking at coilover options like powertrix the spring rates flip?
Using swifts F-12 R-11
I suppose it has to do with the OEM damper valving...but seems like I read long ago that most rear wheel drive cars would/should have stiffer spring rates in the front.
I suppose our cars ride is maybe a clue. With fairly low spring rates in general in the front and rear... the harshness of the ride must be in the way the engineers tuned the valving in the dampers? ...so perhaps this is why the spring rates are stiffer in the rear and less in the front on our cars. However, when you switch to coilovers the valving is more "normal" and spring rates then switch back to a more agreed upon normal of stiffer in front and less stiff on the rear?  |
They're just dialing out the inherent understeer by increasing the rear spring rate at the cost of ride quality. You can change the sway bar diameter but any increase is just tying both halves the the suspension together even more so than the stock setup. And the Z has a massively staggered tire setup too which doesn't help in that department. I ended up with a square setup on my G and it made a very noticeable difference in the car's neutrality.
I use a 12f/10r setup and I'd consider going down 1-2K in the rear but then I'd bring the understeer back. On decent roads, it's a brilliant setup with body roll virtually eliminated. It'll get a little firm out back while on really nasty roads but the fronts always seem to work really well. I've been driving round Southern California for the past few days and they'd be borderline acceptable. Had no idea Cali had such poor roads.
If the rear sport shocks don't do it for you, and you're willing to wait a few weeks, order a set of the Aragostas. No real downside and they're the only kit that can keep you at stock ride height (even above) and they have superior response/damping compared to the Nismo shocks.
Another option is to go with Infiniti IPL shocks. Same as the Nismo shocks with slightly different valving. I found they did not have enough low speed compression damping but the ride was super comfy and otherwise spot-on in the handling dept. No crashing or otherwise out of control body movement (and on a heavier car).