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View Full Version : Right front srping angle?



Pete
03-06-2013, 08:40 PM
Was wondering what most chassis builders run for angle on right front? Moved right front suspention out 1" (Rockect Blue) shock angle looks abit much but dont wont it to hit a-arm during camber gain. Is there a figure to stay within? Thanks for any help.

7uptruckracer
03-07-2013, 07:55 AM
When I was at Rocket this was addressed and they don't worry about it. They said for what it would take to change the shock location back to the other angle you wouldn't notice it

HOTDOG
03-07-2013, 11:47 AM
What about spring rate change for each inch you move the bottom out. I went from 17 5/8 to 19 5/8 and longer upper and it started to coil bind.

7uptruckracer
03-08-2013, 06:58 AM
That doesn't make sense..... More angle in the shock would make it act stiffer. Has to be some other variable like too soft or a short spring

Matt49
03-08-2013, 07:39 AM
That doesn't make sense..... More angle in the shock would make it act stiffer. Has to be some other variable like too soft or a short spring

When dealing with front a-arm suspension, more angle in the shock does NOT make it act stiffer.
Taking shock/spring angle into account only, wheel rate is at it's maximum when the the shock/spring is perpendicular to the ground. Wheel rate decreases as you lean the shock/spring inward. But the decrease is not linear, you need a bit of trig to figure it out.
There are other variables however, the main one being the motion ratio. When you start moving the lower mounting around, the motion ratio changes.
It's explained pretty well here:
http://performance-suspension.eibach.com/motorsport/products/suspension_worksheet

You may be getting the misconception of more angle making it feel stiffer from right rear suspension which is partially true there. The spring angle or the RR has opposite affects on wheel rate than it does on roll rate but that's an entirely different discussion.

Obviously if you are in any type of coil bind situation that's a completely different story as you'll end up with a drastically progressive rate until complete coil bind when it is rigid.

7uptruckracer
03-08-2013, 09:29 AM
I might be thinking about RR. Its early and coffee isn't working. I just know we don't pay attention to it, and rocket said not too lol

Matt49
03-08-2013, 01:19 PM
I might be thinking about RR. Its early and coffee isn't working. I just know we don't pay attention to it, and rocket said not too lol

Yup. There are plenty of other things you should get dialed in before you conclude a change like this needed. Although more and more cars are coming with options on this. Just what we needed...more adjustability :-)