Nohachi's suspension ramblings thread

[SekiguchiUeno]

Good thread Nohachi you speak out of my mind mostly, although i have much to learn.

I am not sure about the data i provided, not sure about speeds, need to meet Reinhard and get the graphs in my hands.

That pickup pic is nice, thats what i always try to explain to some jdm fanboys around, springrates found mostly on ready to mount coilovers are unrideable the body starts to act like spring itself and can disturb the shocks.
But thats logical, the 8/6 coilovers setups from Japan started as some racing oriented setups for caged cars with slicks on smooth tracks.By mistake some guys explored that they are very good for drifting and gymkhana with their lack of grip and almost no travel, the rest is history, we all know the crazynnes of jdm petrolheads, they are able to run high modified cars without shaken on public roads.
None of the sets availlable is approved for road use as i know, only for offroad say track use(so was the greddy i god with my last car), that most guys mount it and use on the road is another thing. So you cannot blame the factories for very high springrates that are made for different conditions that the setups are really used. You can blame them for using the hype for better sales without to explain or trying to redesign.
I was trying to use 6/4kg spring on the greddy and was constantly on bumpstops but not only at cornering but also on every bigger bump. Ended up with preload that gave me exact the same negative travel like 8/6 springs. Some little hard to noticeable improvement of comfort was seen on good roads, not worth the change as the other things in my opinion worsened.Problem of the fancy coilover setups in general is lack of the stroke. You can get stiffer springs on them but not softer ones to make compromise.

Last year i let me made some custom springs with 3,6f and 3,2r springrates to match the stock bilstein shocks as some locost perfect road setup. They still are lying in the garage as they made them shorter as i wanted. As more as i read your threads i want give them a chance again, probably let me made some spacers(Jondees idea but need to design it right to trust them) to try them out. I also bought some Apex springs which are around 2,5-2,7kg to have some direct fit stiffer springs. Bilsteins seem to be overdamped on stock springs and from some calculations i figured out that 3,8/3,3 would be the perfect choice, but 3,8 probably too much for front stock B6. Frequencies i had calculated for 3.8/3.3 are around 1.9hz(F1.924/R1.866) which i found to high from your explaining and the optimung site.

Btw: Miata seems to have stiffer body than ae86 hatch to me.(miata on HKS6/4, ae86 on Greddy 8/6) You really hear the metall twisting and also some rubing from doors and hatch as the body is moving(mostly on uneven roads where the lack of negative travel cannot match the axle crossing.If the road surface bumps not exceed some point, the suspension feels quite comfortable. I can imagine to have tons of fun with them on some small cart track. But i am not the driver that can handle it on roads (massive understeer or oversteer).

My English explanation sucks so i hope all is understandable.