Just got my ATR rear bar!!!!

[GNVAIR]

I still have whatever springs that were on the car when I bought it. They definitely look like cargo coils. Yes, the rear end is stiff, but like I said it isnt bad. I ordered Moog 6435's. I am going to try some different combos. Such as 6435's with the stock sway bar. We shall see.

 

[J Banning]

Thought I's post a couple of thoughts here...

We've got the ATR bar on three cars with Southside bars, and one car with Hotchkis bars. Aside from needing longer bolts, the install on the Southside bar cars were as simple as can be. The Hotchkis car, now that was a little different story. The ATR bar needed some heavy persuasion (eg: sledge hammer) to get it in. Maybe it was just this car, maybe it wasn't?

-Banning.

 

[GNVAIR]

My ATR went right in with my boxed control arms. Maybe the Hotchkis bars are wider??

 

[Kid with a toy]

My turn.

I have stock coils, stock LCA's, ATR, and run KYB shocks. I have an unbelievable hole shot due to weight transfer (no 60's yet). TurboGN has an ATR, rate-wound springs, Bilstein shocks, and Hotchkis everything...his weight transfer sucks. He launches straight, burns the holy hell out of his tires, and comes back pissed.

Why does my car transfers weight so well? I'm still not sure. The only thing we can figure, is the combo. Cornering is great with the ATR, but as said before, my LCA's are shot.


GNVAIR,
My contortionist days are over. At 6'3'' and 245 pounds, I don't bend like I once did. So I think I will follow your idea and remove just about everything I can. I just so happen to have a set of shafts sitting in front of me. So in the next couple of weeks I'll start cutting, chopping, and welding.
Thanks,
Erik

 

[GNVAIR]

Kidwithatoy........the best thing I can tell you is that it was a lot of work. We estimated that we had well over 6 hours into doing the rear control arms (scrubbing, glass beading, cutting plates, welding, powder coating and pressing bushings. If you plan on doing what I did, I would highly recommend getting another set.
I also recommend removing the axle from under the car OR working on a lift to install the bushings that are pressed into the axle for the upper control arms. They are very diffiicult to r&r laying on the ground. I think the work and money were well worth the effort. Although, I still want to try out the new coils springs with the stock sway bar. I have them sitting and might do them tomorrow if it doesnt rain again.

 

[Ormand]

Weight Transfer

Changing the rear roll stiffness, with heavier springs or a heavier sway bar, will shift weight transfer from the front to the rear. In extreme circumstances, with one end much stiffer than the other, you can lift an inside wheel during very hard cornering. Old racing Ford Lotus Cortinas lifted the inside front, lots of stiffened front wheel drive cars will lift the inside rear. There is a possibility of getting oversteer, if you make the rear too stiff relative to the front. Even with stiff rear springs, and a "soft" sway bar, it is possible to unload the inside rear wheel to the point of losing traction. Think about it. If you corner at 1 G (it makes the numbers easy, even if it ain't realistic) you will shift weight from the inside wheels to the outside wheels. The amount of weight is determined by the track and the height of the center of gravity. The only thing the suspension settings can change is the distribution of the weight shift, front to rear. Example- you may shift 1000 pounds from inside wheels to outside wheels. If you make the rear too stiff, and try to resist the roll with rear axle only, you don't have 1000 pounds on each rear wheel, so the inside wheel would would either lift, or become unloaded, which is the same thing, it just isn't as obvious. For drag racing, none of the above matters (much).
George W
Raleigh, NC

 

[GNVAIR]

Re: Weight Transfer

Originally posted by Ormand
Changing the rear roll stiffness, with heavier springs or a heavier sway bar, will shift weight transfer from the front to the rear. In extreme circumstances, with one end much stiffer than the other, you can lift an inside wheel during very hard cornering. Old racing Ford Lotus Cortinas lifted the inside front, lots of stiffened front wheel drive cars will lift the inside rear. There is a possibility of getting oversteer, if you make the rear too stiff relative to the front. Even with stiff rear springs, and a "soft" sway bar, it is possible to unload the inside rear wheel to the point of losing traction. Think about it. If you corner at 1 G (it makes the numbers easy, even if it ain't realistic) you will shift weight from the inside wheels to the outside wheels. The amount of weight is determined by the track and the height of the center of gravity. The only thing the suspension settings can change is the distribution of the weight shift, front to rear. Example- you may shift 1000 pounds from inside wheels to outside wheels. If you make the rear too stiff, and try to resist the roll with rear axle only, you don't have 1000 pounds on each rear wheel, so the inside wheel would would either lift, or become unloaded, which is the same thing, it just isn't as obvious. For drag racing, none of the above matters (much).
George W
Raleigh, NC

We have been over this quite a few times.

 

[Ormand]

Over and Over

We have been over it many times and it is standard suspension design, not something new and different, but still some folks want to reinvent the wheel. I was just commenting that roll stiffness can be controlled with springs, or with the sway bar (anti-roll bar) and that there are trade-offs to be considered. Not to mention that the extremely stiff rear suspension will "bind", since the G body 4 link is not designed for the control arms and bushings to be rigid. But that's a cornering issue, not a strip issue. Just boxing the rear arms will increase roll stiffness, and might provide "enough", with the heavier bar. It would be logical to try it with the boxed arms before committing to the bar, if the intent is to improve road handling, rather than straight line traction.