jreiter

iTrader: (6)

Okay, bit of a concern about Hotchkis springs. Maybe there's more to it, so hopefully you experts out there can clue me in.

Does anyone know why Hotchkis would make their 350Z springs 30 lbs/in stiffer in the front than stock, and 20 lbs/in softer in the rear? This would just increase understeer a bit, right? From my knowledge of suspension tuning, wouldn't you want to tune things as much as possible with spring rate, then just use swaybars for fine tuning?

This concerns me because I ordered the Hotchkis TVS kit. I'm now debating whether or not I even want to use the springs. I have the Koni shocks, and perhaps those combined with the stock springs (and Hotchkis swaybars) would be fine. I really don't need to lower the car any, but that seems like the *only* thing the Hotchkis springs would get me other than increased understeer.

jreiter

iTrader: (6)

Ah, I think I figured it out. The Hotchkis springs are designed to work with the stock shocks. Since the stock rear shocks on the Z are generally considered to be a bit underdamped (thus the bouncing on certain kinds of road), Hotchkis decided to soften the rear springs a bit to compensate.

Since I bought the Koni shocks, I'll no longer have the underdamping problem. This pretty much negates my need for the Hotchkis springs other than for lowering my car (which I really don't need to do in the first place). So, maybe I'll just keep the stock springs with the Koni shocks.

Anyone want to buy a brand new set of Hotchkis springs?

jreiter

iTrader: (6)

(oops, double post deleted...)

VandyZ

iTrader: (2)

Here is an email I got from John Whatley of Hotchkis:

jreiter

iTrader: (6)

Thanks for posting that. It does make sense, however I'm still feeling that their findings are based on the particular valving of the stock shocks. I'll bet that if they used more strongly valved shocks (like the Konis) that rear bouncing might go away.

I think it's just two different ways to go about it. Hotchkis made springs that work better with the stock shocks, and Koni made shocks to work better with the stock springs.

I mean heck, there are guys around here running springs with *way* higher spring rates than stock (in the 400's and higher), especially the coilover systems. I'm guessing that with the right shock valving they don't get that bouncing even with dramatically increased rear spring rates.

VandyZ

iTrader: (2)

Yes I agree.

Thats why I went with the RSR and higher rear rates . I like the way the car feels now. A little oversteer, but not bad. I was probably just real used to the stock understeer. I still want to get some hotchkis sways to get that last bit of adjustment. I have been too busy with other projects to even get some here.

jreiter

iTrader: (6)

Which shocks are you running with those RSR springs?