Rear traction bar discussion.

[muddysub]

I think as long as the bar is close to center the shackle length matters less. I have a lot of travel in the rear and used a 4" shackle IIRC and have no issues. Even a big arch spring is limited to the travel available in the spring shackle. I use about 2 inches of slip on my driveshaft so I can assume its not a real big deal.

As far as length. Like everybody else I read to make it as long as possible. I ended up with a lot of anti-squat in my design. Chris at ORD said the length had less to do with that than the angle the bars are set up at. I opted to make my shackle above the crossmember and ended up with a fairly steep angle.

Yeah I can see the angle having more of an affect on the anti squat than the length. At only 5" lift and the ability to make the bar 65" long mine won't be too steep. When I get home I'll take some measurements and figure out the angles. I've got the square tube at home and the $$ to buy the needed parts. Maybe I'll go ahead and get it done sooner than later.

 

[ryoken]

Mutt needs this soooo bad it ain't funny....

BB, 4 spd with soft 56's and dually under a balsa stage tends to promote wheelhop, especially when ya have a heavy foot


but I'm gonna wait till I inboard the springs to build one...

 

[Blue85]

Length of the bar for anti-squat is an interesting theoretical discussion, but many will find that packaging is the main driver. The long wheelbase rigs have some options, but I think sticking in the same ballpark you see the K5s set up at you should be fine. I don't know if I hit a magic length or if anti-squat isn't very sensitive to bar length in this range, but my rig launches flat.

 

[muddysub]

Length of the bar for anti-squat is an interesting theoretical discussion, but many will find that packaging is the main driver. The long wheelbase rigs have some options, but I think sticking in the same ballpark you see the K5s set up at you should be fine. I don't know if I hit a magic length or if anti-squat isn't very sensitive to bar length in this range, but my rig launches flat.

How long is yours? What angle is it at?

 

[nvrenuf]

Blue85, can you post pics of your traction bar?

 

[Blue85]

See Post #28.

 

[muddysub]

See Post #28.

I like that one. That's basically what I had in mind for mine.

 

[nvrenuf]

Oops, I saw it but missed the fact it was yours. Thanks.

 

[jthod]

Here is a good underside shot of my traction bar installed.

Martin

I saw the hill, more like cliff, this happened on last weekend. I'm guessing you had to change your shorts after that high speed uncontrolled reversing.

 

[82355]

Nope. I mostly just laughed after I found out I didn't hurt anyone.

Martin

 

[jthod]

I can imagine the spectators might have been a bit worried

 

[folkenheath]

I've got a question. How long should the bar be? Length was briefly mentioned but hasn't really been discussed. I've heard "longer is better" and I've also heard that it should be "tuned to the application."

As for the length, I was told as long as possible, but I'd be curious to hear if there was a better answer.

Martin

The best way to determine the proper length is to calculate the anti-squat and adjust the length and frame connection height to achieve the anti-squat you desire. You can trick the 4 link calculator into doing this for you by simply inputting the same dimensions for both sides and also putting the upper and lower links at the exact same frame connection point (wherever your frame mount is for the traction bar (ignore the roll center, roll steer, etc as they will be wrong).

However, I think if you do this you will find that you will not be able to get it low enough or long enough to get a good antisquat number with a lifted short wheel base 4x4. Which is why everyone says to make it as long as possible. I will add to that and say make it as long and as low as possible, because it will stick out and drag on stuff well before it would be too low for a good antisquat number.

Also, where it mounts to the frame is the critical part, shackle being up or down changes the angle of the actual bar, but does not change where it acts on the frame. So the fixed mounting point on the frame is what matters. Which is why you are better off having it mount low on the frame and having the shackle travel up, because that will likely have a better antisquat percentage than having a higher frame mount and a lower angle on the bar. The shackle can create an illusion with the bar angle even though the frame mount could be in the same spot.

 

[82355]

I though you died?

Martin

 

[Deuling]

I though you died?

Martin

 

[82355]

Marty, do you have other pics of the bar besides ones with the blazer on its side?

Martin

 

[Blue85]

I discovered an accidental benefit of the rear traction bar. You can put the handle of a pipe wrench in it, with the jaws on the pinion yoke while you hit the pinion nut with an impact or "el-pipe-o" crush sleeve crusher. Mine happens to have a hole close enough to work. If I was building one again I would intentionally put something there to line up with the yoke. Just a tip.

 

[folkenheath]

I though you died?

Martin

Lucky for me I'm still around, just haven't been around in a long time, probably over a year. I've moved back to the midwest (WI) about a year ago and have been busy with the house/shop/property and now have a daughter as of 2 months ago, so I haven't been around here much. But the truck is still alive and so am I.

 

[folkenheath]

BTW, you know you are a lifelong CK5 member when you think of Martin every time you see a sonic commercial. Let me explain, at the end of every sonic commercial they show this symbol, which reminds me of stock Chevy hub caps, and whenever I think of stock Chevy hub caps it reminds me of Martins obsession with them!

 

[jekquistk5]

BTW, you know you are a lifelong CK5 member when you think of Martin every time you see a sonic commercial. Let me explain, at the end of every sonic commercial they show this symbol, which reminds me of stock Chevy hub caps, and whenever I think of stock Chevy hub caps it reminds me of Martins obsession with them!

Yup i do the same thing.

 

[munepit]

Yup. Every time I see a Chevy hubcap I think of Martin. And also when I see an orange engine.