how short can they be? im making a 4link for my t coupe and i dont have very much room, so the uppers could be no more than probably 11 inches. and also what is the max angle you can have for the uppers. i want to have as much angle as i can get on the upper while still getting all the articulation, well as much as it could get anyways aha
11" is fine for the upper links. You probably aren't dealing with a lot of travel. If you are talking about included angle (between the upper links) 60-90 degrees will work fine. Most stock setups are around 90deg. Hope this helps.
i have pretty much the same amount of room for the arms as Littlemans' Death Door Step does. Im trying to figure out a setup that will make my car hook and launch really well. here is a pic. of deaths door step. bout the same amount of room im dealing with.
ive been trying to figure out that whole instant center thing, but that has been toooo confusing. ive been reading a book on it all day and im just as confused as when i started reading it haha. so im just looking at other setups people ran that race and get as close i can to it.
man i feel ya the more i read about instant center, roll center all that it just makes it more confusing. so i asked some guys around here about their four link set ups any they look at me with this glazed expression when i mention roll center, anti squat or instant center and they say something brilliant like just pur the wheel center in the wheel well and put the pinion in level and it should be fine. ooh thanks lots of help. how did it go with your rearend set up?
not sure how "correct" it is, but i always put my instant center right at the front bumper of the car/ truck. been told that a couple times by pretty smart fellers, seems to work for me.
This thread has a quick and dirty way to see your instant center. http://www.jalopyjournal.com/forum/showthread.php?t=347788&highlight=instant+center
Those books can confuse you. To simplify, on the axle side is a mechanical ratio; axle being the point everything works around. The bottom bar pushes and top bar pulls, best to have bottom pushing at a greater ratio than the top bar pulls. If you look at a drag race ladder bar you'll see the top bar about 2" above the axle and the bottom bar about 6" so it is 3:1. If you look at the first pic showing littlemans' you'll see what i think is the bottom bar and it is welded to the center of the axle tube. That thing won't hook on velcro.
I agree with the location.......when I made that location a few years ago, I was not sure exactly where the optimum location would be.....I talked to Morrison and they talked me into that location.....You can even see in their parts book that is how they have it still.... I had my doubts for this setup for drag race purposes and that's why I started a thread on this design the other day....I was hoping to learn something so I might not waste too much time.....My plans to revisit and revamp will go on, I plan to build in [2]maybe 3 more raised adjustment points on the upper rear bars @ the upper side of the axle and fab up [2] more upper adjustments on the same upper bar upwards as well towards the front.......But I bet I can make it hook the way it is.....I broke a valve spring on the first 392 and hurt it testing the setup and it seemed to work really well.......I believe you need to try different things and go from that point.........I have been told several times you can't do that !..I have been able to throw theory out the window a few times......Thanks for that info ! It makes good sense and in the direction atleast where I am heading with my setup...........Littleman I have been thinking about this, the mounting points on the rearend that is.......someone explain with all the theory's out their...why my Model A Pickup rear set up works so well....They bolt on towards the lower part of the axle tube and nothing on top....and has a track locator and two coil-overs and that's it.....It ran 10.37 with no problem..no tire spin ever....to me that throws theory out the window...?........granted their's allot of factors that are in play like overall weight and such.........but when someone say's you cannot do it because of this or that....might not be true.....The only way you will know is if you try it for yourself.........the best learning tool of all......Dave
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