Thanks for reading this thread. This is a long post. please bear with me. I would like to run some ideas of mine by anyone out there currently running ladder bars on they're car, like Stephen 87 IROC and others. Keep in mind that I am interested in a car that performs well on the dragstrip, and not a car that can go around a corner. But it will be a car that has to be driven on the street some. And yes, I know how ladder bars are on the street. pretty much impossible. But read on, I am interested in a unique set of ladder bars.

I was originally going to keep the stock style suspension and just upgrade it with the BMR trac pack, lower control arms, lowering brackets, drag race sway bar, etc. etc. etc.. However, after adding up what all this stuff would cost to purchase, I didn't like the idea so much anymore. Another factor is I am planning on putting a different rear end under the car that does not come with a torque arm mount (8.5 inch 10 bolt out of a friends truck - it's free for the taking), and I don't really want to buy a bracket from strange or whoever it is that makes them for $150 and make it work if at all possible on that rear. So I'm thinking it'll be much cheaper to work with a ladder bar setup. I wouldn't have to buy any of the things I was originally planning on purchasing, other than shocks and some moroso trick front springs.

I am interested in these ladder bars: Ladder Bars
I would like to purchase the Pro Street ladder bars, do any of you have experience with them, or know someone who has? I am not too sure how much just a couple of bushings in the end of the ladder bars will help with letting the rear twist some on bumps while driving on the street. Please let me know what you think of them.

Also, another quick question regarding the 8.5 inch 10 bolt. Am I going to be able to use the axle tubes off of a 10 bolt or 9 bolt that I have laying around? Cut them off and weld them to the 8.5" housing? I have heard of guys doing that with a ford 8.8 inch and a 9 inch. Assuming I could , what would you do for axles and brakes?
If I can't go that route, I'm assuming I can just shorten the axle tubes on the 8.5", cut off and weld on the spring perches, etc. onto the tubes in the right locations, and get some custom length axles made? But then the brake question still needs to be answered. What do you all think?

thanks for reading such a long post, let me know what you think!

 

Swapping axle tube requires using an alignment jig to make sure everything is square. If the tube is misaligned, it will break an axle.

 

Thanks for the reply. So, swapping the tubes between the stock rear and the new 8.5 can be done is what your saying? what axles would be used?

I plan on having a couple friends of mine who have done this before help me make the jig. I have personally never done something like this, but I have good experience with fabrication. I'm just gonna use my head, and ask allot of people like you what should be done.

 

Depends on the size of the tubes. Axle tubes are not all the same size.

Why do you want to swap tubes anyway? If it's to shorten the diff slightly then you're going to need custom axles.

 

Well, my reasoning behind swaping axle tubes was I thought it might be easier than cutting off and rewelding the spring and shock perches on the 8.5 axle tubes. Also, I do want to shorten the axle tubes, since it is coming out of a truck. it would be too wide, I haven't actually run a tape measure across it to know how much wider it is, but just by looking at it I can tell.

I can also tell just by looking that the axle tubes on the 8.5 diff are definately larger in diameter than the 10 or 9 bolt axle tubes.

Custom axles aren't a problem. I'll just order them when I know how long they need to be.

What about brakes then? I'll just re use the stock drum brakes on the 8.5" rear? What did you do for your 9" that you put in your car?
Your car has actually inspired allot of my ideas. I like how much cheaper and easier it is to set up ladder bars when putting in a custom rear than sticking with the stock torque arm setup.

did you check out those ladder bars I posted about? do you think that is a bunch of crap that they help with bumps and such on the road since they have a bushing in the front rather than rod ends?

thanks!

 

Cutting off the mounts from the 7.5" housing and welding them onto a new diff is easy. I cut mine off with a torch not caring about the tube but trying to save as much of the mount as possible. Take lots of measurements and weld the mounts onto the donor diff making sure all the angles are correct. Swapping the mounts is a lot easier than swapping the tubes.

I use Ford 11" x 2-1/4" drum brakes. That was the easiest way to do it. My rims are a dual bolt pattern so they fit on Ford and Chev car bolt patterns. The trick was to find a lightweight drum that didn't have huge cooling fins. The auto parts store brought out a selection of drums for that size that used the Ford's 5 on 4-1/2 bolt pattern and I picked the one I wanted. I don't even remember what car they were designed for. Even with the tiny factory disk brakes up front, I have no problem slowing down from 132 mph. You can still do the Ford brake swap and keep your Chev rims. You just need to get the axles with the Chev bolt pattern and redrill the brake drums to Chev bolt holes. I don't have a park brake system so figuring out how to make that work is up to you.

I looked at those ladder bars and didn't think much of them. Ladder bars work like a door hinge. When one moves, the other also moves. This means when one tire goes over a bump, the tire on the other side is also forced up. Putting poly/rubber bushings in the mounts is only going to reduce the road noise. I can't see them lasting due to the abuse of street driving. A 4-link system is better as it allows the axle to raise and lower on each side as it goes over bumps. It just needs a lot more setup to know what holes are best for the bars.

 

Well it sounds like I'll just keep the axle tubes in place then, and weld on the brackets! problem solved!

What about moving the ladder bars as close to each other as possible? That would bring the front mounting points closer together, making bumps/potholes/ body roll in cornering have less of an effect, since the center of the diff rotates much less than farther out on the axle tube.

Would that, combined with the urethane bushings up front make it livable enough on the street, and not break anything?

If the ladder bars will simply just be impossible on the street, I guess I could stick with the torque arm setup, I just want to get away from that because of the extra cost of components and I'd have to have a bracket for the torque arm.

I'm certainly not going to tub the car and install a 4 link at this point in the game.

I wish there were a way to install a 4 link kit in our cars without modifying the rear subframe rails too much. Is it just that the rear rails have the wrong angle or something? Too weak? I don't understand what the big deal would be with installing some brackets on the rear rails, and maybe some custom length bars made if the universal kits that are designed for backhalved cars wouldn't fit.

What about installing a crossmember for the 4 link to mount to? Anything wrong with that? too weak?

I must be missing something huge, because it doesn't seem all that much more work than installing ladder bars now that I'm thinking about it. I guess I need to spend some more time under the car with a tape measure or something.

 

with either setup ladder or 4-link you will have to change your floor pans for clearance. the ladder bar kit you have the link to does not have the frame rails you will also need and the cross members and that will add at least 300 + to the price. spohn crossmember with ta is 395 with out cross 310.lcas 115.panhard 95 . so for less you can use these part and get a donor rear to cut off the brackets to use. plus there are no floor mods to make. disregard this if car is a race only car.

 

But using a torque arm means using a third gen diff or buying an aftermarket bolt in diff so you can attach the torque arm.

You can use ladder bars on the street. It's just that you're going to notice a lot of noise. It's not something for a daily driver.

You can see pics on my web site on what I did to the rear floor to get the ladder bars in. Third gens have a very low floor line in relation to the driveline.The ladder bar front mount is technically inside the car or at least close enough to the floor to put the top of the ladder bar inside the car.

Distance between the ladder bars won't make a difference in how they work. They're still 2 solidly mounted bars with a single pivot point. Think of a sway bar that doesn't flex. The sway bar allows the diff to go up and down but if one side lifts up, a non flexing sway bar would lift the other side. About the closest you want them together is 24" unless it's a fully tubbed out car.

 

...another thing about putting the bars closer together is that they have less leverage over the rear-end. - Basically, especially with poly mounts, too close together and the rear could twist sideways in the car.
...4-link - There's nothing back there to tie to. Nothing even remotely strong enough, or that has enough leverage over the whole car. Thats why it requires complete back-halfing.
...diff - as previously stated, just shorten the axle tubes. Much simpler. If you insist on the 10-bolt, then go ahead and get 9" bearing retainers for the ends of the housing and get axles made for press-on bearings(thus eliminating the c-clips) Then run drum or discs that fit Ford housing ends. That's the simplest way. IMO- too much work/$ for a 10-bolt. 8.5 10-bolts are still a 10-bolt and still easily broken. By the time you get axles, bearings, a good carrier, a gear, etc... you'll have in it atleast the same as what a 9" would cost you and you'll probably still break it.
- as for ladder bars on the street, they're gonna be noisy, and they're not gonna do well with bumps. They'll take it, but they'll try to twist the car everytime one tire tries to drops/raise without the other. The bars won't allow it, so they twist on the chassis. The poly mounts would help the noise some, though.

 

Well, I guess I'll take everyone's word for it that a 4 link can't be installed without backhalving. For now I'll stick with ladder bars. maybe in the distant future I'll go back to a torque arm, although I highly doubt it. I'd rather spend the extra money on backhalving for a 4 link.

I'm just confused, because if a crossmember in Stephen 87 IROC's car is strong enough to tie his ladder bars to, why wouldn't it be strong enough for a 4 link to tie to? I realize that the crossmember would have to sit much farther back than his ladder bar crossmember, and it probably wouldn't be able to tie into the subframe connectors. Is this why it wouldn't be strong enough? That is still confusing tho, because the subframe connectors tie into the back subframe anyway, so why would it be weaker to mount the crossmember for the 4 link onto the rear subframe? I really don't care about cutting up the floor, I'm not going to have back seats.

At this point, I'm gonna stick with the 8.5" idea, because the rear is free. Otherwise, yes I'd go with a 9". Know this though: the 12 bolt's ring gear is only 0.375" larger than the 8.5 ring gear. I've seen plenty of them hold allot of power. And my new motor is only a 383 SBC with RHS heads, putting out about 550 at the crank off the bottle. I think the rear will deal with it ok.
Budget 10-Bolt Upgrade - an article about the 8.5"10 bolt
We'll see!

Thank you for all the help so far, and Shagwell, I like your idea for eliminating the c-clips.

 

the 12-bolt is much beafier and isn't prone to flexing as much as a 10-bolt. The ring gear may be about the same size, but case/housing flex is what breaks the gear. Plus you can get much larger/stronger axles for a 12-bolt.
- as for the 4 link, the upper bars need something to tie to. The lowers could be tied via ladder bar crossmember height, but the uppers pull on the car and are around 6" or better above the lowers(adjustments vary greatly). You have to have enough strength up that high/higher to carry the car.

- as for it being free, I'm on one of the tightest budgets you'll ever see in this hobby. But I've said it time and time again..."If you can't afford to do it right the first time, can you afford to do it again?"

 

I was looking at some pictures of the pre-welded comp-e 4 link/ frame rail kits, and I see now what your saying.

I think I've decided to purchase the ladder bars.

How bad will it be when I try to take a corner? lots of understeer from the ladder bars fighting the body roll and lifting weight off the front tires while in a corner?

one more question regarding the 4 link though:
what about using a coilover kit that moves the shocks/ springs inboard, mounting the tops to a crossmember that mounts in between the subframe rails where they go over the axle, then putting the 4 link where the LCA's usually go, welding the bracket straight onto the subframe rail? That way the top of the bracket would be solidly welded onto the frame.

And if that won't work, what about still using a crossmember to mount the foward 4-link bracket to, and making some right triangle shaped pieces of steel that would be welded above and below the crossmember where the bracket is welded onto the crossmember? Then the bracket would be solidly mounted onto the crossmember. I think it would have to be one beefy crossmember though, and some really thick steel that the "gussets" would be made out of. Not to mention the crossmember being solidly mounted to the subframe/ SFC
Can you visualize what I'm saying?

Just some ideas. thanks!

 

- All 4 4-link bars are usually longer than our lca's. Atleast the same length. Now, go a minimum of 5" up and a max of around 12". You have to be able to mount the upper bars up that have and have enough strength to carry the car(as in pick up the enitre front end by pulling back) from that point. It takes much more than a gusseted crossmember. You's have to have some sort of full frame rails that basically went up and over from directly behind the front seats, hence the back-half. As for tieing into the factory rear-subframe...not even close to strong enough.

 

Just wanted to say thanks guys for all your help, I completley understand all that I was asking about now... appreciate it.

Gonna use ladder bars right now.

Hope I can help you in return sometime on these boards. That's what it's all about

 

i wish you would stay with the torque arm...come up with a way to mount it to the housing....that's what i'm doing with my 8.5" project. i'm a sucker for stock style suspension cars though.

 

Ladder bars are a horrible idea on the street and here's why. You will get NO body roll with ladder bars, none. You won't need a sway bar because your entire rear end is the sway bar. Think about it with both ladder bars welded solid to your rear end, how are they supposed to twist? Have you ever rode an ATV? What do they do in a corner? They lift the inside rear tire. This is going to be scary on the street. It will probably push really bad untill your outside front suspension compresses enough to get the inside rear off the ground and then it will go into snap oversteer and spit you off the road. I don't like ladder bars, even on a drag car.

 

Nothing wrong with ladder bars on a drag car. Mine launches hard and straight. It's a cheap, simple suspension setup that can work with any type of rear spring suspension. You just don't get as many suspension adjustment options as a 4 link. Although a 4 link would be prefered, not everyone can install or set them up to work the way they're supposed to. 4-linking means major work to the back half of the car and many people are not willing to do that expense. For most people, if they can get the setup close to what they want, they never change it.

I also don't think ladder bars are good for the street. As I already mentioned, although you can run them on the street, it shouldn't be on a daily driver.

 

I'm gonna try to stick out my 7.5 10-bolt if/till she breaks. Then its 9" time....

 

Do you have any ideas thus far as to how to mount a torque arm to the housing? I considered buying the bracket from moser that is made to weld to the 9" housing... It's what they use in their bolt on 9 inch housings they sell. But I have NO idea if that would even remotely come close to working, and I don't want to shell out $150 for one anyway if I don't have to.

Any ideas mw66nova?

 

The 9" mount bracket is designed to be welded to the 9" steel housing. The bracket itself isn't welded on but some huge mounting tubes are, then the bracket is bolted to these tubes.

A GM housing is cast so welding anything onto it is tricky. It needs a strong enough weld to take the stresses that the diff will put on the torque arm. Welding to cast isn't as easy as it sounds. There's a good chance the housing will become warped because of the amount of heat required. Cast needs to be heated up with a torch before being welded on.

An aftermarket bolt in 9" or 12 bolt housing will be cheaper and easier in the long run.

 

i'm going to come up with a bracket that welds to the axle tubes...though i haven't really come up with anything final yet.

 

- bridge across the top and bottom of the axle tube with a bent piece of pipe. Then have a set of tabs that bolt to each and bolt to some of the cover bolts(like 4per side?) - you know have something to tie to
- build a tq arm that offsets over at the back and ties to one axle tube(via a ladder bar type mount) then build a "clamp" bracket around the pinion for strength
- bracket from one tube that offsets over towards center, around the housing and is braced via pipe from the other tube. - then "clamp" bracket around pinion for strength.

there's several ways it could be done with a little know-how and inginuity. I wouldn't try using a stock-type tq arm, I'd build a bracket I liked, then build a tq arm to suit. - I've got a regular 12-bolt and a 9", so I've looked at several possibilities.

 

i see how your talking, would you make it a bolt on unit or once you got it bolted into place, would you weld it on? also, i'm planning on running an aluminum cover with braces, would you have it bolt ontop of the cover, or make a piece that goes between the cover and housing (like a spacer for a carb, but it'd be the rearend cover...)

 

I'd weld the bracket, bolt the tq arm up. If I went the route of tieing off the cover I'd make a set off tabs that bolted to the brace and bolted to the cover so that the cover could be removed. - I don't think I'd build it as a spacer between the housing and the cover, my luck I'd never stop the drip.....

 

here is what i came up with, i know i'm not much of an artist, but i think you can see my idea.

 

That's basically one of my ideas on how to do it. - You wouldn't really have to end at a stock type mount though, you could just build the tq arm full length to the bridge pipes. Then just build a small bracket that bolts to the tq arm(adjustable for pionion) and to the pinion/front of the diff area. The rear braces(diff girdle) from the cover to the axle tubes would just be for diff strength though, I don't think I'd go as far tieing them to the tq arm bracketry.
- I guess we probably outta post this. - getting a bit off topic.

 

No no! your not off topic! I'm glad someone came up and shared their idea for the rear end! I would love to stick with a torque arm, but the ladder bar setup just looked much simpler to setup. Please, keep the ideas coming!

 

- what I listed is basically the only way I see it possible to mount it and maintain the needed strength. I'm going to a full chassis and still sticking with the sliding tq arm suspension.(big believer in the tq arm) I'm shooting for 1.4X 60fts on 17" dr's.....we'll see.