big basset

Has anyone tried putting 400 model springs on the 300 models

GSteg

iTrader: (15)

They're all the same.

phillygs3

iTrader: (5)

I think the 400/430 weighs a lil more

GS FONZy

iTrader: (6)

Yeah, 50lbs

There are some companies that make different springs with different rates for the 3s & 4s. Also, I read some where that oems are different rates as well, but I don't know if that's true. Call Carson and ask because some companies do use the same springs for both models, but then again some don't.

Faraaz23

There is actually quite a difference in stock spring rates. The GS400/430 has higher spring rates (= stiffer) than the 300. I don't think there is much problem using springs made for the GS400 on a GS300, but I wouldn't go the other way around. Using 400 springs on a 300 in effect is using an aftermarket spring that does not alter ride height (they will be stiffer but still the same length). This is because conservative applications, such as Tanabe NF210, for the GS300 are still softer than the stock GS400 spring rate.

Keep in mind that suspension does not just act when you are turning left and right. When you press the throttle and send power to the rear wheels, you are creating a violent rotating force which we have all come to love. The problem arises in that the V8's produce much more torque than the I-6 does and using a softer-than-oem suspension on the GS400 can have detrimental effects on your setup. Your rear end will squat more under full throttle starts and you will possibly cause some understeer.