[itsmecord]

I have decided on a four link rear suspension for my 36' sedan,but dont have the $$ to buy a premade kit,and even if I did what fun would that be ?
So here is my question (s) I have no understanding of just what is "behind" a four link setup. I was measuring on my car today and was wondering if it would work properly if I used my factory front spring mount as my lower bar mount ? Then make a upper mount once I decide on a triangulated setup,or to go with a panhard bar. If this would work like I see it,then I would have a 28" lower link eye to eye,and a 20" upper link eye to eye,with there mounting points riding 1-2" behind the axle. If my lower links bolt onto the rear end on a parallel line,and my lower bar is "almost" level at approximate ride hight then that would give me a difference in length of 8" in length at their forward mounts. I read that my upper links should be as close as possible to 3/4's of my lowers total length to be optimal,and my upper links should angle down at the front slightly. Is this true ? At this point I would need to set my pinion angle for final welding,what would the best angle be ? street car,hard take offs,shooting for minimal tire spin. I would run fixed bushings on the front and rear of the lower bars,and the front of the uppers,while I would have an adjustable rod end on the rear of the uppers to fine tune. I would be running a coil spring setup similar to a camaro's with a standard transmission,and a healthy small block. Car should weigh in at/around the 3000 lb. mark.

[OneMoreTime]

You need to study what Billy Shope has written on the subject of rear suspension design..

http://www.racetec.cc/shope/

Sam

[Irelands child]

Until you have an understanding of what goes on "back there", this is not something you want to attempt yourself. Then, of course, do you have the welding skills needed to do this keeping safety in mind as well as not ruining a perfectly good differential and mucking up a frame. The info listed by Sam is great and I have bookmarked it myself for later because I for sure would like to know more.

Dave W

[1957plymouthhemi]

I've got a 37 Dodge Pickup project that I'm considering changing from leaf spring to 4 link.

I'm just in the brainstorming phase right now but this is the direction I'm leaning.

Rather than re-invent the wheel I'm looking at picking up an 8.5 10 bolt from a T Type G Body. The reason for this rear end selection is that it should be strong enough to hold up to rest of the drive train (early Hemi/727) and as it's from an OD car it should have the gear ratio I want (3.42 or 3.73) and it's also the right width 58" flange to flange.

The G Bodies were set up with a triangulated 4 Link, I'm kicking around using the stock control arms after I box them and off the shelf aftermarket adjustable upper control arms.

I'm thinking it should be no more complicated than building brackets on the truck to duplicate the factory control arm angles (although I will probably make the upper brackets adjustable to optimise the instant center.

What start me thinking about this conversion on the 37 was when I set up and installed the 9" under my 83 El Camino/Cad 500 swap and realised the G Body rear end was the right width for the Dodge PU.

[itsmecord]

welding will NOT be an issue, I have welded everything from a chevy truck frame that I shortened,to body panels,and roll cages to sandrails. So far none have come back with ANY issues.(years of use) I will go over the posted site,but my question is.....if I am to do like the posted link says and have all my "final' info already recorded how do I get that info such as total final weight,corner weight,ride hight,wheel base,and all when I need the rear end mounted to get all those figures ?

[BillyShope]

Originally Posted by itsmecord

...how do I get that info such as total final weight,corner weight,ride hight,wheel base,and all when I need the rear end mounted to get all those figures ?

Good question. There's no way around it: You're going to make some guesstimates. Everybody does it, so don't let it worry you. It's important that you make these YOUR guesstimates. Don't let someone else make them for you.

I'm saddened when I see that a racer has spent a great deal of time and money and has ended up with a car that closely resembles one of those Shriner clown cars used in parades. In other words, devote considerable time to estimates of weight distribution. If you don't get it right the first time, it's almost impossible to fix later. Use your estimates to calculate weight transfer based on the acceleration corresponding to your necessary 60 foot times.

In other words, I'd suggest that you initially spend more time at the kitchen table than at your welding bench.
http://www.racetec.cc/shope

[itsmecord]

thanx for the input.at least I know that approximate guesses can still tally up to a working setup. I know the wheelbase,and my target weight for the car. But not necessarily where that weight will all be. Out of pure curiosity if there is that much involved in a link type deal,HOW are after market "hot rod" shops turning out so many parallel four bat kits ? And on a "universal' basis ?

[Irelands child]

Originally Posted by itsmecord

. Out of pure curiosity if there is that much involved in a link type deal,HOW are after market "hot rod" shops turning out so many parallel four bat kits ? And on a "universal' basis ?

Easy - cut out then weld up a bunch of parts, advertise then sell via rod mags, then give you some "general" installation instructions on where to do your weldments. Making them work right - that's up to the buyer

And yep, my AVATAR car has rear 4 bars, but they are fully adjustable and were a part of the TCI designed and built chassis

Dave W

[itsmecord]

I am amazed at the crap being marketed today,I mean damn can you buy anything quality these days ? I would have thought there would be some regulations from keeping a place from doin that type of stuff. I will do some more research on the dynamics of it all and maybe build a few models then go full scale.Thanx everyone.