Question: has anyone tried a kind-of 4 link rear traction setup?

[juddski88]

Check your tune and make sure you are not defueling when your truck shifts. You should have plenty of traction with your setup.

What gear/4wd setting are you pulling in? Any TCM tuning?
Look at trying different tires (BFG's?). What tire pressures are you running front and back?

Dix

the truck does defuel, I have done a little TCM tuning but only to increase shift rpms and WOT enable point. next is a 1st gear delete..we currently pull in 3rd, 4-lo, T/H. we have 33" toyo MT's that are maybe 10% worn. i run between 40-50 psi in rear and 20-30 psi in front...depending on track. we have 285 silent armors that are almost new that we are gonna try for these last two pulls..they are very hard tracks...so we will see what kind of rpm/speed we get there. I know we have a ton of traction, what i am trying to figure out though is if it is traction where we need it.

 

[juddski88]

Are they under or over the axle?

Under.....

If they are under the axle as most are, they are actually in compression not tension.

you are correct....so what would be more useful in a long bar though?? compression or tension?

2" schd80 will definitely get it done.

this is an interesting concept in itself....since the bar is actually being compressed, is it creating additional lift of the front end? If the bar was mounted topside on the axle housing, creating tension, would it counteract front end lift?

 

[Texasmax]

Do you hang weights? Maybe you are over HP the track(s) with your current setup. Have you tried rolling into it vs. just dropping the hammer at the start?

I've seen several guys spin so bad at the start that when they finally make traction the sled is already on them.

Just be glad you are being beat by Duramax trucks and not a Dodge.....or worse yet.....a Ford.

Dix

 

[ROGUE GTS]

this is an interesting concept in itself....since the bar is actually being compressed, is it creating additional lift of the front end? If the bar was mounted topside on the axle housing, creating tension, would it counteract front end lift?

It is absolutely trying to lift the front of the truck. Granted without a true link setup it won't have a lot of anti-squat to really drive the rear end into the ground.

But yes, adjusting the length and pivot location of the bars moves the instant center and changes where the "lift point" actually is.

 

[Leadfoot]

The problem with that is when a bar mounted below the axle is compressed, it forces the front portion of the spring to go into tension (A good thing as it prevents axle wrap and forces the spring to be a "solid link"), but when a bar is placed on top of the axle it goes into tension and forces the spring into compression and allows it to bend or "S". With solid blocks this effect is lessened but still there (reason my gasser hopped this spring) and causes wheel hop.

I feel the Cal-Tracs are a better solution against front end lift vs. a long bar. Although the more parallel the bar the better or even angled down (but that is killer on ground clearance and would most likely prevent you from going over the scales......).

Those long strong bars are better at preventing axle wrap (no doubt in my mind), but they have to be lifting the front end a little. The Cal-Tracs may not be as good at preventing axle wrap (although no-one has had issues that I know of) and don't transfer as much lift to the front. I think Tony and others have a ton of power to spare and can hang weights, so it not as much of an issue, but for us I think it's a bigger concern.

I believe in this theory and MadMaxx on DP pretty much proved it.

Just my .02

this is an interesting concept in itself....since the bar is actually being compressed, is it creating additional lift of the front end?Physics dictates that it would (every action has an equal and opposite reaction) If the bar was mounted topside on the axle housing, creating tension, would it counteract front end lift?

 

[juddski88]

thanks chris......i actually never thought about this part of it before until yesterday...so maybe I'll try connecting the bars to the top of the housing as well, like the caltracs, and see what happens. although the only problem then may be the mount...since it would have to be welded to the u-bolt plate on top of the spring pack....don't know if it would be enough force to shift the u-bolts around and jack things up

 

[Leadfoot]

thanks chris......i actually never thought about this part of it before until yesterday...so maybe I'll try connecting the bars to the top of the housing as well, like the caltracs, and see what happens. although the only problem then may be the mount...since it would have to be welded to the u-bolt plate on top of the spring pack....don't know if it would be enough force to shift the u-bolts around and jack things up

The Cal-Trac's link attaches BELOW the axle to tabs on the spring plate (I believe just like Tony's). They go up to a pivot plate that pivots on the front spring eye. That attachment point is only an inch forward of the front (of the rear spring) mount, instead of 6 more feet forward like the long bars.

Here's pick of one on a toyota but same idea

 

[juddski88]

my bad....for some reason i remembered them attaching to the top and bottom of the housing. i have seen some like this somewhere.....hmmm.

 

[Texasmax]

Mine are just like in the picture.

Dix

 

[2wd_Sled_Puller]

JUdd i sent u a pm

 

[Leadfoot]

my bad....for some reason i remembered them attaching to the top and bottom of the housing. i have seen some like this somewhere.....hmmm.

My gasser HAD them on top (maybe that's where you saw them) and I hopped like a bi### until Northampton where we took those off and put the traditional style bars on.

 

[juddski88]

so i am resurrecting this....trying to see if anyone has indeed put a camera under the truck and found out what happens to pinion angle with caltracs mainly, and to see if anyone has any new thoughts

 

[racinmike77]

Just thinking out loud, since you have enough power to spin out you obviously need traction correct?? How about a dedicated set of boggers to pull with?

 

[juddski88]

when i first started brainstorming i was looking for a flaw in my setup, since everyone i ran with ran similar tires (street driven mud terrains or x-terrains), but have since come to the conclusion that there was a conglomerate of things against me, 1 being lower HP almost surely, 2 being shorter wheelbase, and in a couple instances my tire pressure choices were poor and i gave up a few feet here and there. that said, if i decide to really make an effort this year, a ded. set of 35" STS will be on hand.

 

[durallymax]

33x12.5 seems to be the choice size for STSs. However they do take a lot of power. If your tracks are loose you may be ok. But if you have hard clay tracks like around here then you may be best off getting a set of BFG A/Ts.

By the sounds of it your tracks dont take much power, especially if a stock turbo truck with a PPE can hit 4th.

Who does your EFI Tuning?? Do you do it yourself or does somebody else??

By simply cutting back my pulse width in my tune, my truck woke up quite a bit.

Are you allowed to hang weight?? If so I would put your truck on a diet to transfer more of it out front if you can spare the looks to do so.

When it comes to the traction bars, refer the the KISS method. Keep your scedule 80 bars, they should be fine.

I hated my caltracs,l ran them for two pulls, never stopped boucing in either one. The first pulled bounced bad a blew up a halfshaft. replaced that the next moring for a pull that night and hopped again only to get rearended by the sled.

just a few ideas

 

[juddski88]

http://store.summitracing.com/partdetail.asp?part=art-tri1000&view=1&N=700+150+

looking at this kit to build off of, I would try to find larger tubing and links but i can't find rubber-bushed or poly-bushed links
i would do airbags and coilovers. and i think it would only cost between $1000-$1500 depending on what i can find for coilovers. any thoughts?

 

[TrentNell]

http://store.summitracing.com/partdetail.asp?part=art-tri1000&view=1&N=700+150+

looking at this kit to build off of, I would try to find larger tubing and links but i can't find rubber-bushed or poly-bushed links
i would do airbags and coilovers. and i think it would only cost between $1000-$1500 depending on what i can find for coilovers. any thoughts?

i think its a great idea i would like to do this same thing 1 day if i ever get the stones to try it i would hate to spend all that money and find out i dont like it or its not functional . and as far as the kit i would have to see it in person before i made a jugement in streingth and what i would keep or ditch . i really do think this is the best choice for performance and ajustability . there is a reason all forms of motorsports choose a link setup over leafs doesnt matter if its baja or drag racing most all use in one form or another .

 

[juddski88]

scratch not being able to find stuff, I totally forgot Kyle sent me a PM with info .

htttp://www.suicidedoors.com

 

[TrentNell]

scratch not being able to find stuff, I totally forgot Kyle sent me a PM with info .

htttp://www.suicidedoors.com

thats a good links lots of good stuff there .

 

[juddski88]

so traditional or cantilever???
i like the cantilever for stability the best, and i like the looks of doing the air-over-shock in addition to the big air bag for the rebound, or i could just do a normal shock (no spring) along with the big air bag. or i could do a coilover of some sort