TC rod pivot relocation / Bad Dog subframe connectors / Slotted Crossmember

[johnc]

Are you saying that the LCA mount and the TC mount should be in the same line relative to the center line of the car?

 

Yes, just as if you're mounting an a-arm.

[v8dream]

Yes, just as if you're mounting an a-arm.

 

John,

 

What would be the practical effect of relocating the LCA some distance laterally and leaving the TC attachment point in its original position? This would make a pivot axis which deviates from the centerline of the car, and would create a mild version of a semi-trailing arm. I am not suggesting that this is a good path to take. I'm just wondering what the result would be and could it be detected while driving the car?

[JMortensen]

We were talking about this very thing on another thread here: http://forums.hybridz.org/showthread.php?t=106522. Yes, the end result is that the LCA and TC become a "semi-leading" arm (is that a real term???). Any time that you put thrust on the front of the suspension, as in braking, the tendency will be for the front end to compress. Whether that is a good thing or a bad thing depends on your setup, but that is the effect I am trying to reduce, as my car nose dives hard under braking.

[blueovalz]

What would be the practical effect of relocating the LCA some distance laterally and leaving the TC attachment point in its original position? This would make a pivot axis which deviates from the centerline of the car, and would create a mild version of a semi-trailing arm. I am not suggesting that this is a good path to take. I'm just wondering what the result would be and could it be detected while driving the car?

 

Practically speaking, it depends on the amount of lateral displacement, and the compliance in the suspension. Assuming a worst case scenario of a 1" shift (assumed to be outboard for increased camber, but if the car was lowered very much, then this amount would be much less), and even with the OEM compliance, I think it would be safe to say the effect would be negligible. The very slight change in caster and camber (as compared to the OEM settings) as a result this would seem to be one source of concern, and somebody good with trig can provide definitive angles that result from the compliance. But these angles change anyway (caster and camber) and I do not believe the difference (from the OEM changes) would be of any significance.

Lastly, without lengthing the T/C rod, pushing the LCA outboard would pull the axle of the wheel rearward. Guessing the length of the triangle created by the LCA/Frame rail/TC rod (12"/18"/~21.6"), moving the LCA outboard 1" would pull the wheel rearward about 5/8".

[JMortensen]

Hmm... in reading Terry's response it appears I read the question wrong. It was about relocating the control arm pivot and not the TC rod pivot. Oops...

 

In addition to what Terry states I think that if the TC rod points up from the pivot to the control arm there is also more dive under braking, just as there is more roll when the LCA points up from its pivot to the wheel. So moving the LCA pivot up and not the TC rod pivot also has an effect on nose dive.

[Mikelly]

This has been a real interesting thread to read. The more I read, the more I'm concerned about relocating the TC pickup... Hope you get it sorted out Jon! This one might qualify for sticky status only because of the depth of technical discussion in it... Education value for sure.

 

Mike

[johnc]

Moving the LCA inner pivot laterally would do as you've described if the LCA inner pivot was rotated to match the new LCA arc. If you moved it towards the outside of the car you would create a semi-trailing arm and if you moved it to the inside of the car you would create a semi-leading arm. Both would introduce more toe change as the wheel moved through its arc of travel and it would most likely add lateral load to the strut.

 

If the LCA pivot itself remained oriented perpendicular to the vehicle centerline while the LCA moves in an arc that is not perpendicular to the vehicle centerline you would basically have the same situation as now although you you probably have a much different camber curve and proabably introduce more bind at the TC rod pivot and the LCA pivot bushing.

[JMortensen]

OK, I'm back into this one again. Hoping you guys have some suggestions for me (again). I was holding off on this project until my Bad Dog subframe connectors got in. They just came in ...but they aren't going to work as well as I had hoped. If I were just slapping these over the stock rails as they are designed to do, they'd already be on the car. They would be simple to install. Just for kicks I weighed them. They came in at 20 lbs. Weighed the rails and TC boxes that I cut off the car and they were ~14 lbs. Of course, I still have to add the heaviest part, which will be the TC boxes themselves, but I think I'm going to get out of this for about a 10 lb weight gain. Pretty respectable. And for the average Joe putting this on over stock rails on their V8 Z, the 20 lbs seems like a bargain for what you're getting. Enough plugging Bad Dog parts.

 

Took some pics to show the Bad Dog rails, and the problems I'm running into:

Rear part of the rail where it attaches to the rear subframe.

 

It doesn't sit up real tight against the curve between. I suppose that curve might vary between cars. No matter, it connects almost all the way up the sloped part of the floor and all across the bottom of the rail.

 

On the inside of the rear part of the connector it doesn't meet the frame rail, because the frame rail curves right in that space. Again, doesn't seem like it will matter because the connector can attach to the sloped part of the floor, and all the way across the bottom.

 

I just set the TC rod bucket and that part of the frame rail on the car to show how the Bad Dog part would slide on were that part of the frame still on the car.

 

Another shot of the same.

 

Damaged area of frame where I had to fight the TC bucket to get it off the rail. I think I'm going to cut the rusty damaged section out on each side and weld in a new flat section of 1/8" x 3" flat stock. I'll have to do this on both sides.

 

Damage on other side.

 

The frame rail on the straighter floor pan sits about 1/2" away from the rail for most of the length of the rail. I'm thinking about drilling holes along the flange and bolting the floor to the rail to suck them up to each other so that it can be stitch welded. Of course then I'd have quite a few holes to fill. Any other ideas?

 

This shows how far away the box is (roughly) from where the Bad Dog frame rail ends. I'm going to see if I can get them to send me a couple more feet of the channel section like is used on the bottom of the floor. I'll then weld a section of that from the floor up to the TC box.

 

A top shot shows approximately the gap between the end of the Bad Dog rail and the TC bucket. Again, on a stock rail this just isn't a problem.

 

I'm going to have to notch the rail to get the box to sit square, because unlike 74's nice straight rails, the stock Z rail has this long angle from the firewall to the main square section of rail.

[JMortensen]

One more thing. I was thinking of 74's mishap where the TC rod hit the frame. My tentative solution was to take a piece of my roll cage tubing, cut it in half, and notch the frame and weld that section in for increased clearance. If needed.

[tube80z]

It doesn't sit up real tight against the curve between. I suppose that curve might vary between cars. No matter' date=' it connects almost all the way up the sloped part of the floor and all across the bottom of the rail.[/quote']

 

I'd make extensions on the BD rails to come up to this. I think you want this solidly conencted to keep crap from getting up inside.

 

 

On the inside of the rear part of the connector it doesn't meet the frame rail, because the frame rail curves right in that space. Again, doesn't seem like it will matter because the connector can attach to the sloped part of the floor, and all the way across the bottom.

 

I'd, remove the part that covers the end of the tub and move that flush to the rear rail. Then I'd make extensions on the BD rails to come up to this. I think you want this solidly conencted to keep crap from getting up inside.

 

The frame rail on the straighter floor pan sits about 1/2" away from the rail for most of the length of the rail. I'm thinking about drilling holes along the flange and bolting the floor to the rail to suck them up to each other so that it can be stitch welded. Of course then I'd have quite a few holes to fill. Any other ideas?

 

Can you use a jack under the car and some of your tube in the other picture to press this up against the floorpan?

 

A top shot shows approximately the gap between the end of the Bad Dog rail and the TC bucket. Again, on a stock rail this just isn't a problem.

 

Can you use the square tube to create your new TC bracket? Cut flush and capped on the outside of the rail and then openned up on the inside to give you the ears you need for a vertical bolt. Then metal on the bottom spreading the load forward on the frame rail.

 

I'm also curious if BD gives you any info on how to prep these parts. I have a friend that is looking to do the same thing as you. Are you going to use weld thru on the back of all these parts are any other rust proofing?

 

Cary

[JMortensen]

I'd, remove the part that covers the end of the tub and move that flush to the rear rail. Then I'd make extensions on the BD rails to come up to this. I think you want this solidly conencted to keep crap from getting up inside.

I thought about that, but there are a bunch of holes in the stock frame rails, and they didn't have a bunch of crap in them when I took them off. I think the goal should not be trying to seal the frame rails to the floor, but really just attaching the rails to the floor..

Can you use a jack under the car and some of your tube in the other picture to press this up against the floorpan?

Maybe, or John at BD suggested using a 2x4 with a heavy weight inside the car. The car is on a rotisserie and the shell is totally gutted, so if I tried to jack it up I think it might just lift the whole thing. The shell only weighs ~500 lbs. One of the nice things about the rotisserie is not having to get underneath the damn thing to weld stuff like this on, so I'm not real inclined to do it in a way that would require me to get underneath, but I suppose it would just have to be tacked in place, then I could flip it over and do all the real welding...

Can you use the square tube to create your new TC bracket? Cut flush and capped on the outside of the rail and then openned up on the inside to give you the ears you need for a vertical bolt. Then metal on the bottom spreading the load forward on the frame rail.

I'm sure that I could and that tubing is sufficiently burly that I don't think any of the extra crap I had talked about doing before would even be necessary, but from what I read on that other discussion that we were having about rear suspension I don't think I'll have enough travel. As it is the TC rod is pretty much level to the LCA right now, and that was just the last time I had the car on all 4 wheels with suspension but no engine, tranny, etc. With all the rest on I'm sure it will point up. So I want to raise the pivot up at least as much as the LCA's are, maybe more (and move the LCAs up more as well), but that's probably going to take them to level or just a bit down with the weight of the vehicle on the suspension. Since I've sectioned the struts and cut my bumpstops, I just don't think there will be enough articulation in the rod end to allow full compression of the suspension. Mounting it the other way would easily allow for all the articulation I could get, which is why I think I need to do it that way.

I'm also curious if BD gives you any info on how to prep these parts. I have a friend that is looking to do the same thing as you. Are you going to use weld thru on the back of all these parts are any other rust proofing?

No instructions at all. I have one of these though: http://www.eastwoodco.com/jump.jsp?itemID=10966&itemType=PRODUCT so I was just going to drill a couple holes in the rails and spray the inside with Zero Rust. In fact, I was going to do that on all of the frame rails. Then I was also thinking about seeing if I could get the oil that Krown in Canada uses and spray that in there too. I know 260DET has said that you can use fishoilene, but unfortunately for me I'm violently allergic to fish... I think Wurth's HHS2000 would be perfect, since it is a penetrating oil that turns greasy, but I've only ever seen it in an aerosol can. Maybe I could spray from the can into the gun then blast it inside the frame... still figuring that one out.

[tube80z]

Maybe' date=' or John at BD suggested using a 2x4 with a heavy weight inside the car. The car is on a rotisserie and the shell is totally gutted, so if I tried to jack it up I think it might just lift the whole thing.[/quote']

 

Okay, I missed that part. Why not just set weight on the rails? Or are you worried the floor has bowed up? If you have a cage in teh car you can use a porta power to press the floor down.

 

I'm sure that I could and that tubing is sufficiently burly that I don't think any of the extra crap I had talked about doing before would even be necessary, but from what I read on that other discussion that we were having about rear suspension I don't think I'll have enough travel.

 

QA-1 makes a nice new high misalignment bearing good for 64 degrees or so I hear. But then it would be pretty simple to weld on a bracket the has the hole the other way. And you could get real tricky and slot the bracket, use mutilple holes, or a number of other ideas to play with dive if you wanted to.

 

 

No instructions at all. I have one of these though: http://www.eastwoodco.com/jump.jsp?itemID=10966&itemType=PRODUCT so I was just going to drill a couple holes in the rails and spray the inside with Zero Rust. In fact, I was going to do that on all of the frame rails. Then I was also thinking about seeing if I could get the oil that Krown in Canada uses and spray that in there too. I know 260DET has said that you can use fishoilene, but unfortunately for me I'm violently allergic to fish... I think Wurth's HHS2000 would be perfect, since it is a penetrating oil that turns greasy, but I've only ever seen it in an aerosol can. Maybe I could spray from the can into the gun then blast it inside the frame... still figuring that one out.

 

I've used a garden sprayer (deck sprayer actually) and used small rubber line for the tube. You drill a hole in the end of the rail and insert this then let the oil rip. I used WD40 that you can buy in bulk. Other things would probably be better.

 

For my friends car we're going to put weldthrough on the rails and the back of the BD parts and weld then on. We'll probably follow-up with oil.

[JMortensen]

Okay, I missed that part. Why not just set weight on the rails? Or are you worried the floor has bowed up? If you have a cage in teh car you can use a porta power to press the floor down.

Yeah, the floor is bowed up. I have a porta power, but I don't have a cage to push on. Part of this revamp of the car will include a new roll bar, but I still am not ready to commit to a full cage yet.

QA-1 makes a nice new high misalignment bearing good for 64 degrees or so I hear. But then it would be pretty simple to weld on a bracket the has the hole the other way. And you could get real tricky and slot the bracket, use mutilple holes, or a number of other ideas to play with dive if you wanted to.

I'll take a look at that new rod end. I could drill this 3x2 both ways if I really wanted to. As I said I'm quite sure it's burly enough to take the stress either way. I was just going to slot the hole though. Like I said on that other thread, I slotted the crossmember and the control arm hasn't moved on me, so I don't know why the TC rod would be any different. Just another bolt to retorque regularly, and that doesn't bother me.

I've used a garden sprayer (deck sprayer actually) and used small rubber line for the tube. You drill a hole in the end of the rail and insert this then let the oil rip. I used WD40 that you can buy in bulk. Other things would probably be better.

I was thinking of WD-40, but I'd like something that stays put a little better. I suppose it's not too much trouble to oil it up with WD every couple years...

For my friends car we're going to put weldthrough on the rails and the back of the BD parts and weld then on. We'll probably follow-up with oil.

Here's the reasons I chose not to use weldthrough primer:

1. expensive

2. My understanding is that it doesn't prevent new rust from forming at the site of any welds you put through it.

3. Zero Rust is supposed to treat, cover, and prevent new rust, and I found it on sale.

4. EXPENSIVE

5. From what I hear, Canadians swear by the oil. I figure if I do the Zero Rust, then the oil, should be plenty good.

[heavy85]

For what it's worth I used to work with a guy who was into boating and he quoted an article in a boating magazine that tested a bunch of different ways to prevent corrosion. WD-40 was the winner. OK well it's third/forth hand info but with a little research I'm sure this could be verified.

 

Cameron

[tube80z]

Here's the reasons I chose not to use weldthrough primer:

1. expensive

2. My understanding is that it doesn't prevent new rust from forming at the site of any welds you put through it.

3. Zero Rust is supposed to treat' date=' cover, and prevent new rust, and I found it on sale.

4. EXPENSIVE

5. From what I hear, Canadians swear by the oil. I figure if I do the Zero Rust, then the oil, should be plenty good.[/quote']

 

We're not really using 3M weldthru either. We're usign a weldable primer from Napa that's called cold galvanizing compound. Just looking for some extra protection were the metal is heated up. I use zerorust too and like it real well, we have the NW rep her local and he's been a big help.

 

Cary

[JMortensen]

Found those rod ends you were talking about Cary: http://www.bulltear.com/catalog/product_info.php?cPath=28&products_id=131&osCsid=c621fe1d7cde389e37bc0adc2feca787

 

$45 each. Yowzah. That's a lotta coin for 2 rod ends. It would work, but that's a lot of money. I just made a list, and to complete my suspension I'll be needing 26 rod ends or monoballs including these. Still thinking about it, but I think I might just make the box large enough to do it later if I ever get a really irresistable urge to switch it up later. It'd be really cool to do the front control arms the same way, but then you're talking $180 in 4 rod ends...

[johnc]

That's some sturdy stuff! You might think about drilling some lightening holes in non-critical places to get back some of the extra 10lbs.

 

Regarding the bottom rail and the floor pan:

 

1. Get the floor pan as flat as possible with a rubber or plastic hammer. That is a basic dimension reference.

2. Try to move the rail up to the floor pan with a jack.

3. Or, as you thought of, drill a few holes and use bolts and washers to bring things in line. Drill in the center of the rail (not the edges) and use those pilot holes for later, larger lightening/drain holes. Once you get started on this you'll find that things go pretty quick.

[JMortensen]

3. Or, as you thought of, drill a few holes and use bolts and washers to bring things in line. Drill in the center of the rail (not the edges) and use those pilot holes for later, larger lightening/drain holes. Once you get started on this you'll find that things go pretty quick.

Wow. That is a good idea! Thanks!

[JMortensen]

Just got out to the garage for the first time in a few weeks yesterday. Did some more work with the subframe connectors, and more today. Ended up drilling 1/4" holes every 3" or so down the sides of the rails, then pulling the floor up with a self tapping sheet metal screw. Drilling in the middle wouldn't have worked due to the floorboards being pretty messed up. Driver's side is ready to weld on, passengers is in much worse shape, so I figured I'd leave that one for last. Hopefully lessons learned on the easy side will translate to the hard side. Here's a pic of the floor pulled up reasonably well under the rail.

 

Also got new front sections for the rails from John @ BD. They look like they're going to work. Basically they're just like the rail on the bottom, but without the flange on one side so that they can be welded to the rail in front. After I get the connectors connected to the floor, then I'm going to mock up the TC area and then I'll try to do the connectors to the TC square tube, and those pieces to the frame rails all at once. Also notice how flat floor sits against the rail here.

[JMortensen]

Connectors are on! Well, at least the back to the front frame rail, but not the part where the new TC bucket will eventually go. Surprisingly it was easier than I had expected to get the floor to meet the rail on the passenger side. Took some massaging, but what I did was to tack the frame rail at the back, then screw it in place at the front, being careful to align the front of the rail for the next part of the project. Then I screwed in all my sheet metal screws, and where I still had gaps in between screws I just used a big punch and my BFH and pushed the floor out to meet the rail. Made welding the rails on reasonably straightforward. I think this project is looking pretty damn good if I do say so myself! Now that the subframe connectors are on, the next thing to do is to get the rectangular tube on there, then I can connect the short span from the connector to the TC box. Pics:

 

Look at these pretty welds! I love my MM135!!!

 

The subframes are technically connected...

 

I did get SUPER LUCKY with one weird coincidence. My seat bracket just happened to line up PERFECTLY with the frame rail, by pure chance. So I think I'm just going to weld the bracket straight to the rail through the floor. I can even add another tube on the other side and connect to both sides of the rail. I don't think that this is absolutely necessary, but what the hell, right???

 

Here's something a little weird. The way the BD rails come, the rail is spot welded to a piece of angle iron. The angle iron gets welded to the car, then you have to weld the rail to the angle iron. Not a big deal, but you end up with two welds right on top of each other.

 

After first weld:

 

2nd weld: