I am setting up my rear suspension and have some question I'm hoping you guys can help me with. Or give me an idea of what you have on your buggy.

I'm running IRS with out torsion bars (coil over shocks)
Have 3x3 arms and 930 CV's

How much wheel traval can I set it up for...... 10"?
How much cv plunge is possible ..... ? I have 3.5" length differance from bump to full drop.
This is the first time I've done this so I hope my questions makes sense
Thanks

First make the stub axles and drive flanges level with each other. There should be some lateral movement with the axle, somewhere around 3/16" to 1/4" this makes sure the axles are not too long, the lateral movement should be the same for each side. If one side has more than the other the trans is not centered, that should be corrected first. Start to lower the trailing arm while moving the axle back and forth, just as the lateral movement stops raise the trailing arm up one inch and set your limit straps that is max droop. Do the opposite moving the trailing arm up and set your bump stop. There might be some fine tuning needed is there is a bunch of clicking from the cv's at max droop, just shorten up the limit straps some.

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Thanks mike..... Looks like I have the cart before the horse! I still have to nail down what length axle I need and order them.

With a 3x3 you will most likely run a 19 1/4" long axle. It is good to double check the lengths to insure the trans is centered. The way described above is the exact way I set up my coil over suspension. I run a 3x5 rear arm and had to shift the trans back one inch in order to stay within the back angle limits of a race prepped 930 CV.

Mocked up trailing arm with cv and axles installed

Mock up with shock, springs, bump and limit strap in place.

Completed car with weight on the suspension note the 1 1/2 to 2" of droop built in at ride height.
As noted in the procedure above please allow 1" to an 1 1/2" of extra travel beyond the limit strap to keep the cv from binding and the shock from bottoming out and damaging the valving stack in the shock.

Make sure that your CV joints are clocked on the axle as this will allow for the greatest angle without binding the CV. I am not sure which tread but there was a web site that had a very detailed clocking description.

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I have seen that link on clocking, good stuff......... Thanks
I am using a chain drive transaxle so I can place it about anywhere in the frame. My axle length will be in the neighborhood of 15-16 inch axles

What engine are you planing on running? that rear cage looks a little cramped but it just may be the photo. It looks like a great project. The chain drive is quite intriguing, How fast can a chain drive run? If its like a motorcycle I suppose its only limited by gearing.

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Water Cooled Consortium, Chairman of the Build (Former AC purist)

It's a mid engine setup
Engine is GSXR 750. 145hp and only 125 lbs
If I did all the math right, it should do 63 mph in 6th gear at 14k rpm's
I pick up the motor 6 years ago and frame 3, just now gettin to it.

I dont think it will hurt anything and actual help my spring rate but wanted to double check. Would I be able to run my coilover inside the torsion plates and my frame.

The closer the shock spring to the centerline of the axle the better. But with as little weight you have it shouldn't matter.

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Water Cooled Consortium, Chairman of the Build (Former AC purist)

Is there a need to run a bump stop if the shocks have them built in?
Thanks

I would check with race runner to see what they recommend?

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Water Cooled Consortium, Chairman of the Build (Former AC purist)

I would say if it is valved correctly the shock will build high enough pressure to stop bottoming out before it slams the bump stop.....at least most of the time. Bump stop that is solid mounted couldn't hurt though.

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I'm looking at some longer KP arms and spindles. What is your guys opinion on Lastest Rage and Tweeds.
Also is If I go Combo spindles will regular disc fit them?
Thanks!

with your suspension fully collapsed your shock should be at a 90deg angle with your control arm and should lean in about 10 to 16 degs on both sides this will stop body roll from side to side

I would invest in the tweeds if budget is a concern. If you can afford them the Fodril spindles are by far the best.

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Water Cooled Consortium, Chairman of the Build (Former AC purist)

Yea not gettin that crazy lol (fodril)
I think I may go tweeds, I think the Lastest rage are made in china?

That's a good question and surely someone has figured out the math? If the maximum angular deflection of a 930CV is 25 deg. and the length from the transmission flange to the center of the wheel is known then the amount of wheel travel should be able to be figured out on paper. I have to take the suspension apart and hold a ruler and move things up and down because I didn't pay attention in school. It just seems like there are some really big shocks on some buggies that may only have 10" wheel travel? I hope someone gets you the answer.

The cv angle is a compound angle as it is affected by the back angle as well. The shock length is determined by the length of the trailing arm from pivot to center line of the axle. The shock should be mounted as close to the centerline of the wheel for the best control of rebound and compression. Shock valving will affect the speed of rebound and compression.

I don't posses the math skill either to figure it out on paper so I instead Mach it up and take measurements.
I run 14" travel Fox 2.5 emulsion shocks with dual rate kit and external reservoirs. I have a total of 16" of travel from full droop to full compression. I also run a 5" over stock trailing arm with torsion eliminators.

There are many threads posted on this site that go in depth for suspension setup.

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Water Cooled Consortium, Chairman of the Build (Former AC purist)

I suspect that the majority does mock up and use trial and error for suspension geometry. Total wheel travel nevertheless is limited by CV joints and overall length of axles, trailing arms. I too am curious what the amount of actual wheel travel ends up being with different setups.

This is what i have came up with so far
I am running:
10" walker evens shocks
3x3 arms
29" tires
17" axles
930 cv's at 28* full drop
No back angle
2.5" of ground clearance at full bump
I have 13" of wheel travel

Something I just noticed and was wondering if anyone else has ran into this? The front suspension is wider than the rear...... I am running 3x3 rear arms and a +6" front beam with 4x1" arms. I'm sure the width and offset of the rims and tire make up for this, but just seems odd.