I have a 200# in the LR and to get the bite I want I have to put quite a bit of pre load on it. Is it better to just go to a heavier spring, or keep the same spring and pre load it??
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I have a 200# in the LR and to get the bite I want I have to put quite a bit of pre load on it. Is it better to just go to a heavier spring, or keep the same spring and pre load it??
Is this a 4-bar car? If so I'm curious to some of the replies. I just never heard running that much LR bite in a 4-bar. I thought most were in the 25-40 # range. I'm new to the 4-bar so waiting on some replies.Quote:
Originally Posted by dirttrackrocker
I guess I'll clarify a little better. I have a 200# SPRING in the LR and to get 40# of bite I have to pre load it quite a bit, I was thinking of going to a 250# spring with less pre load.
This last race my 200 lbs spring had 375 lbs of preload. 1 7/8" compressed at full drop.
Mark Bush has pages and pages of data on this in his articles ( dirt mod mag)... but the bottom line is the softer spring with pre load (imho) is better because it keeps the car on the spring during hike on the LR...some care and some don't...Quote:
Originally Posted by dirttrackrocker
A spring holds up the LR of the car.... say you have 520# on the scale... minus the lever or motion ratio.... you compress it 2.5 inches and its really a 450# spring anyway...(made up numbers for example only)
If you get a picture of a four bar car up on the bars i can promise you the spring is along for the ride. When the car is up on the bars and with the shocks we run now and trail braking to get keep it on the bars you can through the spring away when you are up on the bars. A four bar car keeps its bite while up on the bars. And as left rear bite goes how about between 60 and 125 pounds.
Think of it this way, if the lr corner alone weighs 540# and you have a 200# spring you have to compress that 200# spring X amount to hold that 540# at your ride height, you will have to add X amount of compression to 175# spring to get it to the same ride height.
The most important thing is that as the car rolls up it does not come off that spring. All cars are diffrent, one of ours takes a 200# 13 inch spring to work, the other a 175# 16 inch spring
Here is an example of how to figure this out
200# spring
1" of compression 200#
2" of compression 400#
3" " "" "" 600#
175# Spring
1" 175#
2" 350#
3" 525#
Again this is an example and will not always work that way but you get the idea. In order to get to the same compression you have to compress the 175# spring more to het to the same ride height.
But to answer your question a softer spring holds more energy compressed to the same weight than the stiffer spring will. The softer sping will promote chassis hike and forward drive, also keep the spring in contact in the bars which will help reduce the tendency to bounce when its at full droop.
Thanks MARK BUSH I have read this article too many times