kohls_66

i hear about everybody using the tubular lca's and relocation brackets, but i dont hear too much about the action lift bars, are they worth the money, do they work better?

teke184

can they even be installed on 3rd and 4th gen style rear suspension??

Injuneer

There was a thread asking about these a few days ago, and someone responded that they were using them, WITHOUT a torque arm.

https://www.camaroz28.com/forums/sho...d.php?t=570484

I think another reason you don't see much of them is the fact that there are 3rd and 4th Gens pulling 1.2x 60-ft times with tubular LCA's.

mdacton

Cause they aren't worth a toot.

search around for Pete-Z bars.

I would never try them on the street, they are not forgiving

FirstYrLS1Z

LCA's(whether OEM or aftermarket) with LCA relocation brackets are the modern day equivalent of 'old school' lift bars.The -3 degrees downward of the factory LCA position is changed to +3 degrees upward with the use of re-lo brackets.That 3 degree upward push against the frame/body results in a downward push of the rearend towards the ground.It's the action/reaction principle.3 degrees might not sound like much but going from a 'designed in loss of traction' to a 'designed in gain of traction' is significant.

I've taken it further by fabricating 'relocation bracket extensions' which have added another 6 degrees to the +3 degrees upward to a total of 9 degrees upward and resulted in too much traction for stock situation.the too much traction was overcome with the convertor.

mdacton

wtf are you taliking about? +3 degrees?

FirstYrLS1Z

With a stock 4th gen f-bod,the LCAs are pointing downward from where they are mounted on the rearend housing to where they are mounted at the frame/body.It is,typically,3 degrees from parallel with the pavement.The lowest hole of the LCA relo brackets now have the LCAs pointing upward from where they are mounted on the rearend housing to where they are mounted at the frame/body.Now they are still 3 degrees from parallel with the pavement BUT at an opposite 3 degrees which equates to a total change of 6 degrees from original angle.The original pushing the body downward toward the pavement,which due to action/reaction,tends to pull the housing/tires away from the pavement is now changed to pushing the body upward away from the pavement,which due to action/reaction,pushes the housing/tires into the pavement.

mdacton

IMO you got it all wrong.

FirstYrLS1Z

Yeah,I got it all wrong,I guess that's why BMR advertises the LCA relos as for increased traction and I guess that's why anybody that installs LCA relos get increased/improved traction.Yeah,I got it all wrong.

Injuneer

I'm not sure that the front end of the LCA's at stock ride height is actually lower than the axle. I don't recall mine being that way.

The concept of the front of the LCA pushing up on the body, and the reaction at the rear axle pushing the wheels/tires into the pavement makes complete sense, though. Keep in mind though, that in lifting the body, an equivalent amount of weight is being removed from the rear springs, which unloads the axle to some extent.

Car Enthusiast

are the relocation brackets for drag strip oriented cars?

FirstYrLS1Z

Relocation brackets are for acceleration oriented cars,street or strip.For general street use and for autocross,for example,the middle hole of the relocation brackets provide a very neutral situation.Neither increased traction or decreased traction upon either acceleration or braking would occur.
Now this entire thread is in regards to stock height vehicles,a lowered or raised vehicle changes everything in how the relos affect performance.

mdacton

its a 3 link rear, the reason for the relo brackets is to keep the stock geometry when you ride ht. is lowed.

If you put them on a car thats stock ht. it won't make it hook better. I know someone with stock suspended rear and cut 1.24 60' on the foot brake and never had them. The lowers arms are just links....they don't put any upward pressure on the car at all....thats what the tq arm does.

I can't get real technical on it, I'm not that smart.
I think it is called a mcpherson 3 link.....search around for a good explanation of what does what. It was designed for the vega I think. Its a good system.

The lift bars change everything and just turn what you have into a ladder bar.

There is alot involved in suspension....don't buy into the hype of alot of crap that is sold. I don't care who sells it or what they say, if someone can hook and go fast without it chances are it not doing what it says it does. If you understand how it all works you will find there are other areas that need work besides relo brackets.

Injuneer

Might want to back off.... the LCA's can produce a force that either lifts or drops the body.

The lower control arms are the only thing that pushes the car forward, based on the traction force developed by the rear tires. If the LCA's were perfectly level, the entire compressive force pushing the car forward would be applied to the body mounting point in a horizontal manner, and would not push up or down on the chassis. It would just push the body forward.

The moment the LCA is not level, it will result in the compressive force in the LCA applied to the body bolt being "resolved" into horizontal and vertical components. The magnitude of these forces can be determined using the geometric "tangent" function.

If the body end of the LCA is lower than the axle end, the resolution of forces will result in a vertical component that pushes down on the body LCA bolt. The equal and opposite reaction on the axle end will resolve into a vertical force that attempts lift the rear axle assembly. This is the situation that is very likely to produce "wheel hop". The tire has traction, the traction force results in an equal and opposite vertical component that lifts (reduces the forces pushing down on the tire) the axle, the tire loses traction, the forward force disappears, meaning the vertical component that was lifting the axle disappears, the tire regains traction, and the cycle starts all over again.... hop - hop - hop.

If the LCA is set up with the body end higher than the axle end, the compressive force in the LCA it resolved into a horizontal force that pushes the body forward, and a vertical force that pushes up on the body end LCA bolt. The equal and opposite reaction at the axle end of the LCA will result in a force that pushes down on axle assembly, improving traction.

The above analysis is somewhat simplified. It ignores the fact that the upward force on the body also unloads the axle via the spring, and the downward force on the body increases the load on the axle at the spring. Its much easier to describe the LCA geometry's direct effect on the rear axle, since its a "static" calculation. Once you add the spring to the picture, it becomes a bit more complex, because of the dynamics added by the spring, the dampening of the spring by the shock, etc.

But simply stated, the LCA can push either up or down on the chassis.

I would also disagree that the LCA relo bracket only helps cars that have been lowered. The largest single improvement I found with the rear suspension was the elimination of wheel hop by using the LCA relo brackets, on my STOCK ride height car. And since you are aware of the capabilities of George's car, and you know it wasn't lowered, when he saw the improvements in my car, his car immediately went to Steve Spohn's shop for the same pieces,including the LCA relo brackets, that Steve had installed in my car. He picked up more than 1/10th in 60-ft time, and ended up with outrageous wheelstands that required a bit of tweeking to get under control.

red1984

What makes you think that running the lift bars without a torque arm is bad?