WASyL

Hi there, i was wondering if anybody has diagrams and dimensions of 4-link suspension for 3rd gen ? I want to build one by my self for drag racing so it would help very much.

best regards

xpndbl3

iTrader: (5)

torque arm suspension is already setup perfect for drag racing. Just buy quality aftermarket pieces and run them. Plenty of guys going very fast on the stock setup

sofakingdom

iTrader: (1)

There is nothing close to a bolt-in 4-link possible. It requires basically cutting off the whole back half of the car and replacing it with something else. But the factory design (not necessarily the factory pieces) is good at least down into the 10-second range. In other words, unless you're trying to go faster than that, it would be alot of maze with very little cheese at the end.

AlkyIROC

By the time you buy the parts to make your own, it will be cheaper to buy a kit. As mentioned above, you won't find anything that will fit under the floor of a factory third gen. Kits are always cheap. Installation is what takes time and money.

Third gen diffs sit high up into the body and don't have traditional frame rails to attach a different suspension system to. The best you can hope for is something similar to a SuperStock suspension where it's tubbed out enough for larger tires but still retains the back seat area and uses a long arm/short arm 4-link system. It would still be cheaper and easier to do a normal back half.

This is the thread to how I did mine.

https://www.thirdgen.org/forums/fabr...ight=back+half

WASyL

i know that it requires cutting off whole back and i know it is cheaper to buy kit, when You live in US, tek say kit costs 2k$, after whole shipping proces i would cost me over 4200 USD, well it is better for me to get whole specification and build it by my own

best regards

AlkyIROC

Get a measuring tape and a plumb bob and start measuring. If you have to ask how to do it then you shouldn't be attempting it. There are no exact "diagrams or dimensions" for what you want to do. You measure and cut until it's made the way you want it. Maybe you'll be able to fabricate some frame rails but you're still going to have to buy a 4-link kit for the tubes and brackets.

Start by reading this book on how suspensions and chassis work before you go trying to reinvent the wheel.
http://www.amazon.com/Door-Slammers-.../dp/0963121707

DIGGLER

iTrader: (1)

take all the stock stuff out, reinforce it, put it back in. add lower control arm relocation brackets to the rearend. add a drag racing swaybar to the rear if you can.

WASyL

I do have all rear spohn+umi including LCARB, i know all what you say, but i always wanted to have 4-link and as costs of shipping are irracional for me i rather do one by my self, thought someone has all the specification, dimensions etc. if not, well ill have to make one just by pictures

best regards

sofakingdom

iTrader: (1)

What's wrong with what you have? What does it need to do differently?

WASyL

there's nothing wrong, i just always wanted to have 4-link drag car, not for results (in my country we do not have a single dragstrip) just for fun and as one another mod and gadget to show

best regards

redneckjoe

have you thought of boxing your current suspension? it wont cost much if you can weld a little.

AlkyIROC

Doing a 4-link requires lots fabrication work. If you don't buy a kit then you build from scratch. There's no set measurements as to where anything has to go. You fabricate to make it work properly based on basic measurements for a 4-link system and fit it to your vehicle.

When I first did mine, I was going to do a ladder bar back half. I plotted out in scale on poster board the shape I wanted the frame rails to be and even purchased some 2x3 square tubing but before I could make the first cut, I switched to doing a 4-link system. I bought generic 4-link frame rails and a 4-link kit and went from there fabricating everything else. I originally went with a diagonal link but before I got the car to the track, I switched to a wishbone system.

You're not going to get a proper 4-link system without doing a back half. Parts for doing a back half is cheap. If you have to pay someone to actually do it, it would cost around $10,000 to have it completely done. Although I've done one, I really wouldn't want to do another. Mine isn't perfect but does well for what I want.

To do a proper back half, you'll also need to install a full cage to add support to the frame rails. The frame rails themselves won't survive dragstrip use without the support of cage tubes.

WASyL

@redneckjoe - have you ever read this thread or just responding to get post count ?

@AlkylROC - thanks for the input, cage is on its way anyway, from what you say i will get a lot of work with this but it still cheaper for my to fabricate whole stuff then shipping it form USA to Europe

best regards

redneckjoe

nope, dont care about post counts, lol. i was only trying to show you another option. sorry if that bothered you for some reason. i wish you the best on your project, have a great day!

WASyL

rednecjoe couple post above i wrote that i have all reat umi/spohn that mostly mean LCA and panhard

best regards

lunati397

our cars already have a 3 link rear suspension and it is a very good design you can benefit from a 4 link if you have a 6 sec car and need the ultimate ajustment capabilities but there are plent stock rear frame cars that are in the low 8s 7s without back halfing the car the bigest pain will be a 4 link setup works good with a car with a real frame which our cars do not have with all the spohn parts that you have you are already good and if you really want more do a mini tub and stuff some bigger tires

AlkyIROC

A 3 link suspension is not what's in a third gen. Third gens use a torque arm suspension. They're similar in design but not the same.

One of the biggest advantages of a 4 link system is the adjustability. 4 link settings can give dozens of settings but only a handful are useful. Since each car acts differently and track conditions change, having more adjustment options allows you to change settings to suit the conditions.

Typically a slow car works better with an IC high and short. The faster you go, the longer and lower the IC needs to be but too low can put the car into tire shake.

That kind of adjustability isn't possible with a torque arm suspension.

Arthur Von Doom

So

Arthur Von Doom

[QUOTE=Arthur Von Doom;6444339]One thing I want to add to this discussion:
I have a 1986 camaro and someone before my time shortened the torsion bar and welded a brace behind the tail shaft to the structure of the car and welded the torsion bar to the brace

I was like "What the F*ck?!" When I first seen it, but it didnt make me not buy the car as I could always make it back stock with a little cutting, welding, and a call to our good friends at classic industries for a new OEM replacement for the torsion bar.

But when driving the car, it HOOKS. (It also has a mild 350 with a th350 w/a shift kit and a 3:73 rear end gear) but the beauty of it all is, its virtually costless, just some rigging, welding, and a little steel stock. The torsion bar would have been bolted to the transmission crossmember with a rubber/polyurethane bushing mount. This is cool and all but that mount has alot of slack in it and also a weak poorly designed mount that cracks, wears out, or breaks in these cars The torsion bar is hooked to the top of the rear end housing, when you floor your car, everything has a little "play" in it. Everything moves. But by solid mounting the torsion bar and taking a few inches of length out of it, it does a world of difference for drag purposes. It keeps the rear end from turning forward, the shortening of the torsion bar made it stiffer and stronger, the brace brought the bar level with the ground and ultimately eliminated practically all and any wheel hop on 235/60/r15 rear tires. It also is multipurposful, as it also doubles as a bad *** drive shaft loop LOL.

like I said I love the idea, and the proof is in the pudding. The car hooks and goes, no issues, no wheel hop, and everything feels tight and good. Ive driven other camaros with the stock set up and/or torsion eliminated (some people are....special...) and I'd say mine:
• HOOKS HARDER
• GOES STRAIGHTER
• RIDES STIFFER (which I'm a fan of)
so my next step is to pretty up the previous owners welds, and then I'm going to box my control arms and most likely switch to a pair of coil over shocks for the rear end.

Also, i always use a semi-solid trans mount. I cant remember the name of the company but it's a steel mount encased with polyurethane. It's got a little but of cushioning to it, yet it's very rigid. They sell them in the goodie section at our local oriellys. Lol also the jegs book etc. I recommend it if you do your torsion bar the same way. Or anything you build in general, GM trans mounts were always a weak point, and it goes back to my theory from earlier about having less "play" in everything making a better "hooking" car.


ALWAYS REMEMBER:
" The Less Play, The Shorter The Reaction Time, Faster And Harder Take Off "


Best of luck, friends.
☆ keep er' rollin' ☆
*Let There Be DOOM!*

vorteciroc

Honestly the Torque-Arm Design Rear Suspension, with aftermarket adjustable tubular Arms...
Make for a very good suspension that provides GREAT leverage via the LONG Torque-Arm.

I do not see any benefit going to a Four-Link System until the Car has started Wheel-Standing.

anesthes

iTrader: (12)

When I had a thirdgen based drag car it hooked better when I switched to the jegster shorter torque arm mounted to the trans tunnel, no longer had wheel hop.

-- Joe

vorteciroc

I personally have never had an adjustable tubular Torque-Arm mounted on the Transmission have wheel-hop issues...
But it is possible depending on the set-up, and the other Rear Suspension Components.

Very few of my Customers Cars used the stock mounting location (and normally got upgraded to a different Mount location eventually).
They almost all get a Sub-Frame Tie-In style Torque-Arm...
and the others got a Transmission Cross-member mounted Torque-Arm.