thinking of building my own 4-link

[elitecustombody]

I think I made up my mind on building triangulated 4 link instead of buying ,just debating if I should use 1.25" ends or 7/8" ,is 1.25 an overkill?I just like seeing beefy arms and knowing I'm riding on sturdy parts, Any input from the pros?

[E.rodz]

try thornbeck bros. they have a website called suicide doors.com they have all kinds of link bars and all there parts are top notch.

[ArtosDracon]

Depends on the kind of end you're using. 7/8" heims will be plenty strong. If you're gonna use delrin or something else remotely pliable, I would recommend going wider, 2" at least.

[silver69camaro]

What do you mean by 1.25" and 7/8"? If it's thread size, I'd do 3/4". No sense in adding more weight for no reason.

[MrQuick]

I thought he was asking about tube size.

def go with 3/4" hardware and 1 1/4" tube.

vince

[Bryce]

I thought he was asking about tube size.

def go with 3/4" hardware and 1 1/4" tube.

vince

I agree with this. My lower links will be built this way and the upper third link will probably have a 1.5" bar with 3/4" rod ends.

[elitecustombody]

What do you mean by 1.25" and 7/8"? If it's thread size, I'd do 3/4". No sense in adding more weight for no reason.

it's hard to find 3/4" bungs that will fit a 1.75" OD tube with .25" wall,are they even exist?

[silver69camaro]

it's hard to find 3/4" bungs that will fit a 1.75" OD tube with .25" wall,are they even exist?

Wait, what? Are you off-roading or something? That size of tube is silly for what we do.

My opinion: 1-3/8" x 0.095 4130 tube.

[Bryce]

thats twice the thickness of the roll cage!

You would be fine with a 1.25"diameter tube and .120" wall thickness.

Meziere has some nice weld in tube inserts. They are local to me.

[elitecustombody]

Wait, what? Are you off-roading or something? That size of tube is silly for what we do.

My opinion: 1-3/8" x 0.095 4130 tube.

LOL, no, I just like having solid suspension, even SLP arms I had on my 95 Impala SS were about that size, I still have one set of new arms for one and I prefer similar diameter arms

[The WidowMaker]

dom 1.5" .120 for my lowers and 1.25" .120 for my uppers. i think thats overkill as well. give ballistic fabrication a call and they can get you what ever you need.

[ErikLS2]

Wait, what? Are you off-roading or something? That size of tube is silly for what we do.

My opinion: 1-3/8" x 0.095 4130 tube.

Engineer= Someone who can do what anyone can do. (At half the weight and half the cost). :)

[DLinson]

I used 1.25 OD x .125 DOM and maid my one inserts. Using 4130 really requires normalizing after TIG welding. It's safer to go with the mild steel and sacrifice the weight. Mild steel yield, bends, then breaks, chromoly tends to just break; not much warning.

I'm running 520HP but haven't had slicks on my Nova and everything is fine. I'm also using QA1 3/4 heim joints teflon lined.

Dennis

[JRouche]

it's hard to find 3/4" bungs that will fit a 1.75" OD tube with .25" wall,are they even exist?

Wow, 1/4" wall tube for trailing arms? Kinda over kill. And Im not an engineer so I tend to over build. But those arms would be really overkill, and heavy.

Remember to think about the weakest link pn the entire system. If the tabs coming off the body are only say 3/16" plate, and the tabs on the rear end housing are 3/16" they will be your weakest area. Even if the tabs are 1/4" plate they will still be the weaker of the components if you use 1/4" wall tubes.

The tubes will see loads in compression and tension. The tabs on the body and axle housing will see side and shear loads. Not to mention what the tabs are welded to. If the body tabs are on stock body parts its a sure bet any excesive loads will shear the tabs from the body before the tubes, even much thinner tubes, will collapse.

Even if you welded 1/4" tabs onto a crossmember that had a 1/4" wall thickness. That joint would fail under extreme loads before a 1.25"x 1/8" tube would. The shearing loads on the welded joint of the tabs will fail long before the tube.

And yes, go to ballistic if you want to make the arms that you want. They can supply the weld in bungs and DOM tube.

http://www.ballisticfabrication.com/34quot-16-tpi-Tube-Adapter_p_1402.html

Scroll down to the size change part. They have the 3/4" threaded 1.75" bungs you need.

I have bought some stuff from them, great company. Make sure to chase the threads after welding and use some anti seize on the shank of the rod end. Thats from a lesson learned. :) JR

[BillyShope]

LOL, no, I just like having solid suspension, even SLP arms I had on my 95 Impala SS were about that size, I still have one set of new arms for one and I prefer similar diameter arms
I'm with you!! There's no reason to compare tubing used as part of a static structure with the elements in a mechanism carrying dynamic loads. When you apply the factor of safety and shock load multipliers supplied by any machine design text, there's no way around it: You end up with sewer pipe. You're quite correct in taking a good look at stock suspension linkage before you build.

As for weight, the difference involved is almost always less than the difference between the driver's weight and the weight he should be at if he wants to live to see his grandchildren graduate from high school.
http://www.racetec.cc/shope

[John Wright]

Engineer= Someone who can do what anyone can do. (At half the weight and half the cost). :)Exactly my thoughts. I would overkill too, just because I don't know enough about crunching the numbers to feel safe. I have alot of respect for the engineers who know their trade....also those guys may even see load paths that I might not even think about, which could potentially open up another whole set of problems.

[ProdigyCustoms]

Hey Elite, I got your message but lost the phone number. Try me back.

[silver69camaro]

Engineer= Someone who can do what anyone can do. (At half the weight and half the cost). :)

Ha! Usually ends up being double the cost! :)

[elitecustombody]

Wow, 1/4" wall tube for trailing arms? Kinda over kill. And Im not an engineer so I tend to over build. But those arms would be really overkill, and heavy.

Remember to think about the weakest link pn the entire system. If the tabs coming off the body are only say 3/16" plate, and the tabs on the rear end housing are 3/16" they will be your weakest area. Even if the tabs are 1/4" plate they will still be the weaker of the components if you use 1/4" wall tubes.

The tubes will see loads in compression and tension. The tabs on the body and axle housing will see side and shear loads. Not to mention what the tabs are welded to. If the body tabs are on stock body parts its a sure bet any excesive loads will shear the tabs from the body before the tubes, even much thinner tubes, will collapse.

Even if you welded 1/4" tabs onto a crossmember that had a 1/4" wall thickness. That joint would fail under extreme loads before a 1.25"x 1/8" tube would. The shearing loads on the welded joint of the tabs will fail long before the tube.

And yes, go to ballistic if you want to make the arms that you want. They can supply the weld in bungs and DOM tube.

http://www.ballisticfabrication.com/34quot-16-tpi-Tube-Adapter_p_1402.html

Scroll down to the size change part. They have the 3/4" threaded 1.75" bungs you need.

I have bought some stuff from them, great company. Make sure to chase the threads after welding and use some anti seize on the shank of the rod end. Thats from a lesson learned. :) JR

I see your point, and I appreciate the input,I just want to feel safe when I beat on the car ,last thing I want is something breaking loose .I'm debating if I should use Currie,Ballistic,Spohn or Heim joints ,I know Heim's will cost less than half,just wondering if it's worth spending extra $$ on better stuff.I plan on going with Ridetech Shockwaves and building suspension to have about 2.5-3" ride height,

Stefan

[elitecustombody]

I'm with you!! There's no reason to compare tubing used as part of a static structure with the elements in a mechanism carrying dynamic loads. When you apply the factor of safety and shock load multipliers supplied by any machine design text, there's no way around it: You end up with sewer pipe. You're quite correct in taking a good look at stock suspension linkage before you build.

As for weight, the difference involved is almost always less than the difference between the driver's weight and the weight he should be at if he wants to live to see his grandchildren graduate from high school.
http://www.racetec.cc/shope

Thank you ,sir. Yes, I'd rather have couple extra lbs in the suspension and feel safer. Now I have to do some reading on your site, Thanks for posting the link.

Stefan

[elitecustombody]

Exactly my thoughts. I would overkill too, just because I don't know enough about crunching the numbers to feel safe. I have alot of respect for the engineers who know their trade....also those guys may even see load paths that I might not even think about, which could potentially open up another whole set of problems.

Haha, I knew I wasn't alone,lol

Stefan

[elitecustombody]

Hey Elite, I got your message but lost the phone number. Try me back.

Frank, I ended up going with skw 7000's,I'll hit you up if I need something, oh, actually I do, you still have the F-body stainless hardware kits? I need one

Stefan

[elitecustombody]

Ha! Usually ends up being double the cost! :)

I wanted to say that yesterday,lol

[JRouche]

.I'm debating if I should use Currie,Ballistic,Spohn or Heim joints ,
Stefan

If it were my car Id look Spohns or Curries. JMO. JR

[elitecustombody]

Looks like Currie joint can not be tighten like Spohn's and Ballistic's when it gets a little worn

[silver69camaro]

I like Currie's rod ends much better...

[elitecustombody]

I like Currie's rod ends much better...

Matt, can you elaborate? Have you used all 3 and determined that Currie is better or is there another reason? I'm trying to make my decision in next couple of days.Thanks

Stefan

[LowBuckX]

I always go the way of safety. Im using 1.5 .250 wall DOM in my 3 link arms. I had to make my own inserts but I feel safe.

[ErikLS2]

I am all for safety believe me but a thick walled oversized arm may not be safer. Proper engineering allows the weak link in the chain to be designed in, but in this case making the control arms beefier may only move the weak link to some other less desirable component, assuming of course that the standard size control arm is the weakest link to begin with (I doubt it is).

Let's say that an accident occurs and a standard control arm is somehow compromised, either bent or broken. Now, in that same accident a much stronger control arm does not break and possibly worse yet doesn't even bend. It then has the potential to become a spear and will go right through any sheet metal it's near not to mention whatever might be seated on the other side of that sheet metal.

I have the luxury (ok, most of the time frustration LOL) of being raised by an engineer and when I sometimes start talking about what I might build or how I might strengthen something I get a quick education in how I'm wasting my time and efforts on the wrong thing.

[elitecustombody]

Erik ,I get what you're saying,but I seriously doubt the beefy control arms would go right through floor ,if 3/16" thick mounting brackets are welded solid to a crossmember or some sort of plate on the floor, the car has to be dropped from helicopter or driving with no rear rails and sheetmetal and exposed rear axle,
my car will sit and pretty low, so if rearended,the rear axle would be out of reach..



Does anyone know what ends are on Heidt'd,Ridetech AirBar rear setup?

Stefan

[silver69camaro]

Matt, can you elaborate? Have you used all 3 and determined that Currie is better or is there another reason? I'm trying to make my decision in next couple of days.Thanks

Stefan

Sending a PM....

[elitecustombody]

Thanks Matt, I really appreciate the info, now I need to figure out the best angles to work with slammed air ride 3" ground clearance.

Do you know if lower links will interfere with 345/25/20 if mounted at the stock location for leaf springs? I see alot of guys use 335's with G-bar and mini-tubs , is it because the tire is real close to the inner wheelwells or it's close to the LCAs or both?

Stefan