Last question for tonight... I hope!

I'm putting a set of Pro-Kit springs on my car, mainly for the looks of the stance more than anything else at this point because I'm just starting auto cross and will probably need to get a set of custom spring rate springs later on as I get better.

Anyway, Founder's is being really slow about shipping out the LCARBs, new LCAs, and Panhard Bar. They are blaming it on a company failing to ship the rod ends to them last week and it's putting me in a bind to have the car ready before the next autocross even that I planned to go to.

So I was wondering if these things are absolutely necessary with a 1 inch drop or if I can get by without them for now? I understand the reasoning behind the LCARBs, the LCAs if angled up don't put enough downward force on the rear wheels causing loss of traction and such. But I didn't know if the 1 inch drop was enough to cause a major problem without them.

If it is enough to cause a problem, should I run the car with the rear suspension unmodified (stock springs and shocks), while the front of the car has already been redone with new springs, struts, and camber plates? And also if I can run the car like that temporarily can it be aligned properly like that? I haven't taken it to get it aligned yet because I was waiting to do the rear suspension work before getting it aligned.

Thanks!

 

You'll be fine without them. I can't remember how far angled the arms are at stock height but you might even end up with them at a perfect angle with just a 1 inch drop.

 

You may well find that "1 inch drop" springs actually RAISE your car; especially if you still have the old wore-out stockers in there.

Best to just see what you end up with; athough, given that the geometry is ALREADY defective at factory ride height and does nothing but get worse as the springs age and sag (or the car gets deliberately "lowered"), more than likely they'd be beneficial. Ideally you want the axle end of the LCA slightly lower than the "frame" end, maybe 3/4" or so. It's easy to get carried away and overdo it.

If properly installed, they have no effect on alignment.

 

Like Sofa said. You could look at my car and the LCA angled downward from the rearend to the chassis. That was with "stock" height springs. With the LCARBs, they are now just slightly upward.

 

Not necessarily true.

For drag racing perhaps yes you want to angle them down, but for some autoX, and most road racing, no. While having them angled down toward the rearend generates anti squat, it diminishes braking performance and it produces roll oversteer which will make the car more twitchy, especially at high speeds. Steering inputs are matched by the rear turning toward the outside of the turn. This makes for a demanding car to drive, especially at high speeds. The more of an angle, the more pronounced the effect.

The other thing to consider is that roll oversteer does not just affect the rear end in roll, but also in bump. If you hit a bump mid corner, this is also going to cause roll steer which again, makes the car more difficult to drive.

Perhaps the best argument against angled down control arms is that they will increase the propensity for the car to brake hop. Having experienced brake hop at around 70 mph on the track, I can say it is not fun. You might have to clean up and change your underwear afterwards.

While it is possible that roll oversteer can be desirable on a slow/tight autoX course, it's hardly as cut and dry as a one size fits all approach.

Generally, from what I have seen, most suspension experts actually suggest a small percentage of roll understeer to make the car more stable, and improve braking performance.

FWIW I have my bars about level which should be close to neutral in roll but perhaps sacrifices some braking performance.

What is often ignored is how the car feels to the driver, the car can never be driven to it's potential if the setup makes it impossibly difficult for a human to extract maximum performance from it.

What you will find out on the track is that a car that is predictable and easier to drive will return better lap times than one that is twitchy and difficult to drive.

Steven, unless your arms are really angled up far, you will be fine. Worst case scenario you won't have much traction out of the corners and the car will have a lot of roll understeer. No big deal.
For the former, I can say that the fix with the greatest benefit will probably come from a good limited slip instead of the angle of your control arms.

 

Thanks,

And yeah Auburn Posi, new gears, 28 spline axle upgrades, and probably bolt in conversions, are the next things on my list of things to do. I decided to do the suspension first because right now I think getting my handling down will help me more than a little more traction out the corners and such.

As for my stock springs and sagging, I don't think they are sagging very much if any. I've seen pics of other camaros on pro kit springs and think they look noticeably lower than mine.

Here is a recent pic of it for you to judge for yourself:

 

Nice looking car.

Look at the LCA. How is it angled? Or is it parallel to the ground?

Does it go up to the body or up to the rearend?

 

I'm with Pablo and the gang. I'd try it with the arms on the factory mounts, no problem. If nothing else it will let you know if the car works well or not as-is.

ramey

 

Pablo, how much emphasis must I put on the word SLIGHTLY to quit getting this "Dean" lecture every time this subject comes up?

 

Relax buddy, the point is that you suggested a one size fits all approach, and I presented an alternative view.

I was not personally attacking you.

Under dynamic conditions (like brake dive) "slightly" can turn into much more, and still causes roll oversteer. How much? I don't know off hand. Maybe we should calculate it? That way we can make informed decisions. You are good at math right?

 

your car looks very low for stock springs..

 

Right now they are angled down from the body to the rear end. It's not a large angle, but a noticeable one. Guessing I'd say about 1 to 1.5" drop from the body to where it connects to the rear end.


Really, you think so? I was comparing to cars in this thread:

https://www.thirdgen.org/forums/susp...d-3rd-gen.html

Post #18 in particular shows a before and after comparison. His car looks like it's sagging more than mine on stock springs, and on pro-kit springs it's even lower. It's hard to tell for sure since he has different wheels and tires in the after, and I think the wheels have a larger diameter.

Post #70 shows another pro-kit that is noticeable lower than mine.

The angle I took the picture at isn't the best for showing the wheel gap, I'll try to get a side shot tomorrow if I have time from the same level as the tire wells.

 

I would just set the LCA angle at level, and then bring it down to the next closest level and call it a day (this is if you have LCARB tho). Setting it slightly lower on the axle side (but as close as possible to level) is the best all around scenario for street/road race in my opinion.. Drag and tight turn autox are different tho as mentioned above..

 

If they are already angled down from the body to the rearend, you definately dont need them.

 

this is probably a dumb question but dont give me "too much" hell about it lol but, what exactly is a LCARB??

 

Lower Control Arm (LCA) Relocation Bracket

 

i feel dumb.. i dont know why i didnt put two and two together... thank you though

 

Don't feel dumb. We're here to help folks learn. And also to learn ourselves.

ramey

 

It is always helpful to write out the acronym the first time. There are some that we get so used to writing that we assume everyone understands. Never feel shy about asking if there is something floating around that you haven't figured out yet.

Lon

 

For comparison sakes here is a pic of my car this morning with the pro kit springs on the front. It seems like it dropped a lot more than 1 inch to me, I really hope they don't settle much further. Having a mechanic install the rears for me today cause I ran out of time and needed it finished up today lol. I'll take another pic later with all of them on.