This is what I started out with

Then changed it to this

Now this is where I am at. The front is almost done!!!

looks good!

Thanks

looks good did you make the A-arm or is this a kit that you had to fab to fit?

I fabricated everything. The a arms are made out of 1" chromoly .100 wall.

i like it its differnt for shure

looks good! wat are your plans for the rear?

nice job

Good job cant wait to see it on the sand.

Well I am staying with the swingaxle because it is mid engine. I am in the process of putting the same style shocks on the rear and maximizing the travel which will hopefully be about 12 inches at the wheel.

you could have your swingaxle converted to and irs and then build a 5 link type suspension

Your not going to get 12" out of a swingaxle !. Maybe 8" depending how wide your setup is. JMO I would sell the SA and go to an IRS 6 rib bus tranny !. It will cost more up front but you will have something worthy to build on from there !. ( not sure if you can do a mid bus trans , if not go for the 4e mendi !) even better tranny !.

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Looks good!!

I looked at that route but I was told by a few people that it would not last. I guess the irs differential carrier bearing is significantly smaller that the swing carrier bearing causing it to have too much load on it when it is used in a longer travel application especially with heavier CV joints like 930s. ANyone heard of this???

I actually have the long axles and end castings. I guess 8" is better than the 3 I had before with the marvin shaw shocks. I am also going to run 1/2 inch wheel spacers also to help with the travel.

Very nice conversion. Did you happen to take before and after dimensions? Is there a difference in wheelbase and overall width?

Wheelbase is about the same. Track width is alot wider cinsidering I was running an aluminum beam with stock trailing arms and spindles. I don't remember the exact measurements before, but it ended up being about 18 inches wider than before.

I saw that you had a pipe bender(not a tubing bender) in one of the pictures. Did you bend your tubing with that?

It looks like the transaxle is more secure with the new design. What geometry goals did you establish for front suspension: King pin inclination, caster, camber, bump steer, travel. Is the design on-paper, CAD, real-time?

I see you double-shear mounted the rear a-arm pivots and left the front single shear. Should work for a light car.

Looking forward to rear suspension work. Nice car!

I can relate ^^^^ , ... I would also look at the long term issues or prospects ,,,,,, Once you get the stock travel , to the Mid travel, you will drive it like it was a LT and be chasing chassis issues forever because you think your car (mt) is capable of LT , 90mph whoop rides and jumps and so on.... NOT GOING TO HAPPEN !. Dont comprimise safety for $$$ , do it right and build up to what you can afford !. There are all different types and $$ on this board that will give you your 2 cents worth of Knowledge... what you do with it and how it effects your life,, depends on your homework an your $$$. jmo...
. dune on !!!.

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No, I have a freind that has a pro tools tubing bender that I used. the pipe bender doesn't work on tubing too well. I did however, use it on a mud racer that I built a few years ago. But then again, I built that out of Schedule 40 11/4 pipe. worked great for that!!!

Well, as far as design goes, I had a general idea of what I wanted. I sat down and started to put some of those ideas on paper. once I got what I wanted I started cutting the front off. I set it up with about 7 degrees caster. I dont remember the exact angle on the kingpins, I will check it tonight with my angle finder and post that. I do get a small amount of camber change throughout the travel but that is something that I can live with. Even some of the big cars I have seen have camber changes from full droop to normal ride height. I dont know how much bumpsteer I will have if any, I still have to fab the tie rods. Based on where I mounted the rack, I should have minimal bumpsteer.

I originally was going to do single shear pivots front and back but, I thought the back might need a little more considering it takes alot more abuse that the front pivots. Plus, the front I am using 3/4" bolts and the rear I am using 1/2" bolts due to the misalignment spacers. I am using 3/4 rod ends on both.

you want camber change... you want the tire to lean in a bit on full droop and bump. this will keep your track width close to the same as it cycles and when your cornering hard the tire will not try to roll... ther is a few other reasons also..

looks good

Hats off to you for doing what most would never attempt!!

Thanks

It is almost done!!!! just need to test, tune then paint!!! Here are some pics of it nearly completed

looks cool your ride will be 100% different. Have fun.

nice job i like it

I LIKE

Great Job! I just started my beam conversion and I hope it goes as well as yours.

Looks good!! Do you have any bump steer? Its not too common for the steering rack to be mounted up high like that. Just curious.

Yes there seems to be a little bump steer. I havent had it out to the dunes yet so I will not know how much or how it will affect the handling. I am hoping it isn't too bad. If it is, then I will cut and re-fab (one of the reasons I will not paint it yet). This is my first A Arm supension build so most of this is new to me. i guess we all have to start somewhere. I did a lot of research before I started.

When I took it around the block, it felt great!! Different feeling having the front end lift. It almost scared me at first when I stabbed the throttle and I watched the front tires suck in and the front lift. Hopefullt I have my spring rate correct. 2 more weeks until I get to test it out!!!!!!!!!!!

Your gonna have a blast....Better bring alot of gas...

Well I took it out this weekend and the suspension worked great! The steering however, was not so great, I had major bump steer problems which I thought I might have. I have the fix for that which is lowering the rack and extending the inner steering rod pivot (moving it more outboard) this will shorten the tie rods to hopefully eliminate the bumpsteer. ANother problem I had is with the rack itself. Evertime I had one wheel going over a hard bump it wanted to just jerk the wheel out of my hands. (thumb buster) Now, is this because of the type of rack I used? I just used one of those small 14" buggy racks. My buddy was having the same issues with his and he uses the same rack. Are there other racks out there that will eliminate this? Any help would be appreciated.

if you mount your rack right inbetween your upper and lower pivots then your tie rods should br the average length of your upper and lower arms. example: upper arm 20" , lower arm 25", your tie rod should be 22.5".

the jerky steering might be your rack or you might not have enough king pin inclination.

couple things. Tlt the top of the tires in a bit, it appears you have them tipped out to match the rear, but you don't need that. Before you change the rack mounts, set the camber up correctly.

Second, it appears that the control rod heim is very close to the spindle body, if it's too close, it will be a bitch to turn and the wheel can yank outta your hand. The farther away the mount is fro mthe spindle, the more leverage there is for turning nd to help resist the wheel yanking. I am assuming you have very quick steering, less than one full turn from lock to lock?

3rd. You can get the bumpsteer dialed out in your garage. Draw a line down the middle of the floor, use some plum bobs to center the rail up above the line, then put jacks under the car so it doesn't move and the wheels are not touching the ground. Pull the front wheel off, let the spindle fully extend and set up a stop with 2x4's or something for the lowest point. Then, pull off the coil's, put the shock back on the rail, then compress it completely by hand and set up a 2x4 stop to represent the highest point.

Make sure the rack is centered up, then lock the wheel so it can't turn.
get a sheet of plywood and set it up outside the wheel, parallel with the centerline on the floor. Get a long level (I use a 4 foot level) and fasten it to the wheel hub, make sure and lock the hub so it doesn't move up and down, and make sure the level is level.

Adjust the control rods so the wheel is parallel to the board, which is parallel with the centerline..

What you are gonna do is measure the the level to the board as you cycle the wheel up and down throughout the wheels travel. I start my numbers at full compression, in other words, I get the wheel parallel with the board with the stop in place holding the wheel at the highest point. I do this because if you have any bumpsteer, you wanna dial it down the the full extension numbers, as it's not as critical. (You don't wanna come down from a jump, compress the suspension, then have toe so bad the car changes direction while the wheel stays straight.) I then have a stop for ride height, and about 5 other stops for 2 or 3" increments. Measure the ends of the level to the board, and take notes on a piece of paper. I have 20" of travel an managed to get about an 1/8" bumpsteer in the last 2" of extension, at 2" I am about 1/16" bumpsteer.

Now, before you do this, set the camber up correctly, and make sure the contro rod mount is the correct distance from the spindle, if you change them later,, you will mess your numbers up..

Bumpsteer is very tricky to figure out, moving the mount up/down or side to side a 1/4" can give you an inch of bumpsteer quicker than you think. I spent about 3 days dialing out the bumpsteer on my current rail...

A little trick I use is to run a centerload rack with a plate mounted to the front of it. I have a slot to go up and down with the inner mount, and I actually move the rack side to side with the steering wheel until I find out where it needs to be for the least amount of bumsteer. You basically just need to know where the rod end hole needs to be in relation to the centerline..

I don't adjust the spindle control rod, just the inner mount. And a little ballpark figure is to start off with the control rod parallel to the upper and lower a-arms....

Don't know if you understand any of what I wrote, but I tried, lol.....

your kingpin inclination looks fine by the way....

Thanks yoshi. Yeah I did understand what you were saying.

I know my rack needs to be lowered because my tie rod are not parallel with my control arms. It looks like I will have to move the rack down about 1.5 inches for them to be parallel. I think that is where most of the bumpsteer is coming from.

You also made a good point about the outer steering rods being too close to the spindle body. They are actually about 2 inches away. maybe they need to be further out?

Yes the rack I have is a quick steer unit. It is just a little over 1/2 turn lock to lock. Is this too quick? I was thinking that is what was causing the wheel to get jerked out of my grip.

1/2 turn from lock to lock is extremly fast. Does it turn for you ok in the sand, or do you really have to man handle it?

from the side of the spindle body to the center of the control rod heim on my setup is 3.5".....

Click to view attachment

Yeah it turns ok. I really don't have to muscle it. I actually like the way it reacts when I turn. I just don't want to have a broken thumb or two.

wow looks like a good job. im thinking very hard about doing the same time thing to my buggy. few questions?

for the frame did u use dotm?

also what did u use to bed the tubes?

What is dotm? Did you mean DOM? I used mild steel tubing (welded Seam). I used a pro tools tubing bender.

Well, I re mounted the rack in a different location and changed the tie rod inner pivot and WOW what a difference. It is amazing how much 1 inch will affect your steering! I took the shocks off and I have zero bump steer now until full droop and then it is only about 1/4 inch. I think this is because of the steep angle the kingpin is in relation to the a arms at that point.

Anyway, my buddy just bought a rail from someone in california (we are in utah) so we went to Baker to pick it up and we brought my rail along so we could go out and play at Dumont since we were going to be so close. Well the steering worked flawlessly. The wheel never once pulled away from my grip and I was driving with one hand on the wheel most of the time. It actually felt like it did when I have the stock beam in it. I think it turned out great! Now I can paint it!

Oh yeah, this was my first trip to Dumont. Really nice dunes. Very soft though. We are definately going to take a big trip down there now since we now where it is and how the dunes are.

Thanks for all the help!!

Well I finally got it painted! I figured I should put some pictures up. I also added some side panels. I will be fabbing up the wing trunk this week. Boy it looks so much different now. Almost doesn't even look like the same rail I started with.

Looks good man. I have been thinking about the same thing.

Looks great. I am thinking a lot of us beam owners will be cutting up our cars soon.

How much travel are you getting out of the front end?