I recently had spohn subframe connectors installed, and installed the eibach pro-kit on my car. Now when I get all over at low speed, like coming off a light or just after I get out of a turn, my just feels all tail happy and stuff. It wasn't near this much before. Me and my dad think that the SFC's stiffened things up so much that it makes my whole car want to let go.... is this what it is? Anyone have any ideas? Thanks.

 

Is the rear feeling loose? If so, get some LCA reloaction brackets installed. It will improve your acceleration/traction.

 

Yup, lowering the car made you need reloc brackets. The SFCs have nothing to do with it.

Your LCAs are now no longer parallel to the ground, instead the frame end is much lower than the rear end end of them, so when you give the car gas, they want to try to rotate upwards away from the pavement.

 

well the SFCs do tighten things up too, there are several people who have switched from a 24mm to a 23mm rear swaybar after installing SFCs because it stiffens everything up, and makes the car a little too loose for their liking. also the new springs will make things alot stiffer too, and of course the drop will efect the LCAs as RB83L69 pointed out. i would first put on brackets, if it still is too loose for you, run a little less rear sway bar, or jump up to a slighly larger front bar.

 

You may want to check the toe out on the front wheels. After lowering your car your wheels will be toed out if you did not get it realigned. This will make the car seem very twitchy. Of course why you are checking the toe it would only make sense to check for excess camber. Your caster should be fine, unless it was off to begin with. My own personal preference is to go to a certified GM dealership for an alignment. Reason being GM actually produced a tool to help align strut equippped GM cars. It helps to keep the mechanic from scratching up the strut towers and hammering on the strut mounts.

 

Adding Reocation brackets and lowering the rear LCA mount angle will create even more oversteer And actually make your problem worse. Tighten up the front end as much you can (Bigger bar, STB, WB all will help- mostly the bar though). I would suggest you run a 34mm solid front bar and a 22mm solid rear bar- Spohn has this exact setup coming out in a package.

Without Relcation brackets and car lowered- result = more understreer (front end wants to push more and not turn)

With Relocation brackets installed and car lowered- result= rear is more neutral steer .

With Relocation installet on a stock height car-result= more oversteer.

You have an oversteer problem already- probably from the front springs not being stiff enough to balance the rears thus making the rear take more of the roll weight of the vehicle. This is rare on a V8 setup- they are much more known for push rather than being loose in the rear. Most of this sounds like a front end geometry change problem to me from being lowered with softer front springs- There are many factors that can cause this all working together- without pyshically seeing your setup I can not pinpoint things for you. Is the car diving excessively when braking- meaning like the stock front springs do? It has to be mainly alignment settings and excessive movement in geometry change.

I should point out that I am the guy that suffered a change in suspension balance when I added Spohn SFC's to my car- however- everything else was already built/lowered/aligned/ adjusted/and balanced to maximum cornering capabilities. The simple adittion of Spohn SFC's stiffened the chassis so much that there was no more frame twist and the rear inside tire began to lift around a corner making the car loose. A simple rear bar diameter decrease solved that problem. I steped down from a 34f/25r (both solid) to a 34f/23r (both solid)- I have a V6 so I can run a slightly larger rear bar than a V8 with my same setup because of less front end weight.

 

Picture of how my car sets; Most of you have not seen it but know me around here for awhile- Finally I took a picture of it.

 

i like the stance.

what spring hieght, and rate are you running? or which spring kit?

 

They are approx. 800# front and 225# rear and were custom taylored to height (In otherwords I cut them slightly 2 or 3 times until it sat where I wanted it. It is a V6 with springs stiffer than most V8's run. Front sits at 24 3/4" to fender lip and has never gound out. Barely dives down at all when I hit the binders- this car stays flat.
Edit: wife drives it pretty much daily- not too stiff for her- she loves the way it rides and handles.

 

you have a 23mm rear bar with that right?

i was thinking of running 200# with my 24mm bar. so i was curious as to what sort of spring rate you were running.

 

Did you also install an adjustable panhard bar to recenter the rearend after lowering?

 

Quote:{you have a 23mm rear bar with that right?}

Yes, 25mm was too big- but fun.

Quote:{Did you also install an adjustable panhard bar to recenter the rearend after lowering?}

Everything is Fully adjustable aftermarket product under this car. The rear end did set about 1/4" to the side when I first lowered it years ago so I immediately added an adj. panhard rod then. The last year+ I have completely upgraded everything under the rear car. It was getting worn and in need- I abuse it any chance I get.

 

Please explain how this could be... It usually the exact opposite effect, by causing the rear to hook better when under power, it adds traction to the rear, which is the opposite of oversteer; it actually tightens the car up quite a bit under power, and has little no effect when not under power. Gives the car "forward bite".

 

This is so hard to explain or even try to draw- but here go's my attempt (I could show you easily with three pencils in my hands how this has an effect on geometry movement through axis roll and causes rear steer (roll steer). The more stiff the suspension and lesser the body roll (axisroll) the less this will have an effect.

If the rear mounts of the LCA's are higher than the front mounts and the car sways or rolls to one side hence lateral g's in a corner - then the axle will remain level (for the most part- not considering tire sway). The inner LCA geometry will lengthen when the inside body rolls upward on its roll axis- thus lengthening its geometry slightly more than the outer LCA geometry and causes outside wheel toe-in/ inside wheel to toe out (or roll understeer).

If the rear LCA mounts are lower than the fronts and the car leans in a corner - then the geometry of the inside LCA shortens/drops more from axis roll and causes the axle to pitch to the oppsoite direction of the corner causing the roll steer of the rear wheels to turn outward from the corner/ toe out on the outer wheel, toe in on the inner wheel.( thus roll oversteer)

Neutral level of LCA's in a corner are best suited for cars with front engine design (more front weight bias) Rear engine cars will generally perfer some bit of roll understeer built into the geometry to help compensate for rear engine weight oversteer.

This is very advanced suspension tuning and hard to grasp to the average person. There are many other factors that come into play such as bushing flex/stress (on independant rear suspensions- rear caster is a big part)

Note that my picture below shows mine setup just slightly lower in the rear while suspension is stagnant- With driver weight, areodynamic force and cornering compression playing into factor, mine will set just slightly understeer in very hard turns- mostly it is neutral.

Is your head hurting yet?

 

There's nothing in there that's beyond elementary suspension mechanics. Anybody that's ever tried to set HITHERE car up to go around HITHERE corner knows about roll steer.

Problem is, that effect is about half an order of magnitude, or more, less than the improvement in rear end traction that results from having the control arms point in the right direction. The roll steer effect has about the same relationshipfor most of us, in quantitative terms, as Ackerman steering has to an oval-track car at 200 miles an hour on 33° banking.

Those of us with some power have an entirely different "loose" problem than an underpowered heavy car (such as one of these with HITHERE 6-cylinder) that practically coasts around the corners has. It's called "tire spin". That's where the LCA bracket helps. All the rest of those microscopic trivial effects of the roll geometry don't matter one whit if you can't step on the gas without swapping ends.

 

Ok genious, IF YOU KNEW THEN WHY DID YOU ASK? My little V6 will take your *** on an autoX course anyday- and Ive got cash to back that!
Edit: Another hotshot V8 guy that doesn't know I own a 540RWHP roadrace Vette and lots of trophies Then picks on my "whimpy" V6 that will hang with my Vette on small courses.

If you learned to setup the car right and drive properly you wouldn't swap ends asswipe.
Ya try to help people and you get guys like this that have to be the bigshot know-it-all but is clueless.

 

Thank you for that display of excellent knowledge and teaching ability, as well as class and dignity. Im sure you convinced alot of people how all of these things really play their part in the car's handling.

Actually, Im HITHERE little disappointed, as an opportunity for learning something seems to have gone by. After all these years of hard-learned experience, perhaps something new and contrary to all known physics of car operation seemed to be almost peeking over the horizon, waiting for the golden chance to show us all some enlightenment. HITHERE was all primed for hearing about how cars with spinning tires could have better steering control and power transfer than cars with traction. Oh well. Maybe next time.

Show me some numbers as to how the effects of roll steer in these cars will overshadow an improvement in power-applied traction. Then Ill believe it.

And no, some Vette doesn't particularly intimidate me.

Autocrossing has its limits as HITHERE test mode, you know, just like straight-line drag racing does. Just wait until one of those Mini Coopers hands you your head on the parking lot course, then bring us HITHERE lesson all about things really work. That particular activity reminds me of chasing HITHERE baby around HITHERE dining room. Ever done that? Doesn't matter how fast you are, how strong you are, how nimble you are; there's still HITHERE whole lot of chair legs in the way, and something that's smaller and lower than you can get around them better than you. Auto-X is alot like that: it tests your car's ability to negotiate chair legs. HITHERE worthwhile, fun, and sometimes useful pursuit no doubt; but not the sum total of the real world. Some of us like to be able to drive on expressway ramps and such, too, and maybe even go to work in the morning without concern about losing it on some curvy road, which is not at all the same thing as autocrossing.

LCA reloc brackets are part of the process of setting up one's car to not swap ends. Which was of course overlooked it would seem.

 

I'm calling you to the table bigshot- you talk big game- lets see pics of your ride- After all, someone's car definately can show someones experience.

 

OK, whatever...

Not much to see, just yerbasic old car; this pic got compressed kind of too much to make it small enough size for something else, sorry for the terrible quality.

 

I get it- this is some kind of Apri Fools joke-- obviously you are in no way any kind of suspension guru with your stock f-body.

It doesn't matter what I have to work with I will not drive something stock- Unlike you, I have a reputation to uphold and drive nothing but true performing vehicles. Heck, my chev truck would beat a stock f-body in a corner.

You just showed your hand, and your naiveness. You really think that thing handles well? If you truely were a suspension guru, you would never drive/own a stock suspension car- they are not safe to performance drive in unless it is an extremely upper end vehicle.

Keep watching your NASCAR on TV and leave the tech questions to us real experts son. You've just been schooled.

 

Where do you get the idea it's stock? (Like that matters to the question at hand)

We're still waiting to hear how a car with spinning rear tires can have less oversteer than one with rear traction under power.

 

Your point is trivial- why?- because regardless of suspension settings, any car when given too much throttle will bring the *** end around whether that car has understeer or oversteer characteristics- this is caused by driver error.

and that my friend is basic physics-when tires spin, they have less traction- you are clueless.

 

So explain to me how a mod that increses rear wheel traction, thereby eliminating wheelspin until a greater power input to the wheels is reached, will make a car oversteer. Every race car I've ever been around, if the rear wheels had more traction than the front, we said it had "understeer" or was "tight"; if the rear wheels had less, it was called "oversteer" or "loose". When a car is loose or has understeer, you do things to it that tend to increase rear wheel traction. That's precisely what LCA lowering brackets do: increase rear wheel traction, specifically when power is applied. Of course any car will bring the rear around when given too much throttle; that's sort of the point of this mod, is to raise the "too much throttle" threshold. Du-uh.

I'm really struggling with understanding your vastly superior and mighty intellect on this ordinarily quite simple and straightforward matter, and how increased rear wheel traction is "trivial" to the issue at hand.

If we can't get some kind of rational explanation from you instead of personal attacks, then we'll all continue to conclude that you shot your mouth off before you put your brain into gear, lacking any evidence to back up your claim.

 

Partner, I explained to the best laymens terms that I could in my above post and you are still not getting it.

LCA relocation brackets improve straitline wheel hop lanch problems and do not help with lateral g traction in the manner you are stating.

I have explained all facts, you are not or refuse to get it. I'm done with this. Thankyou.

I said above it was very complicated- you think you understand but you don't.

 

if you guys read your posts you will find you are both right.

agood2.8, there are those of us who understand exactly the dynamics you are describing. and i am sure RB is one of them.

the point he was making and that i made when i suggested brackets was because of his problem.

[quote] Now when I get all over at low speed [quote]

that sounds to me like he has a traction problem, not that he has a oversteer issue.

at least that is what i got out of what the original poster described. and i think that RB got the same thing out of it.

 

[QUOTE]Originally posted by Dewey316
if you guys read your posts you will find you are both right.

agood2.8, there are those of us who understand exactly the dynamics you are describing. and i am sure RB is one of them.

the point he was making and that i made when i suggested brackets was because of his problem.

[quote] Now when I get all over at low speed

Quote:

that sounds to me like he has a traction problem, not that he has a oversteer issue.

at least that is what i got out of what the original poster described. and i think that RB got the same thing out of it.

Dewey, pertaining to Hg's original question, your guys suggestion of adding LCA brackets will do nothing or potentially creat him a worse problem- It will not help his perticular problem he asked about.

Yes adding LCA's will help him hookup with straight line traction- but will hurt lateral traction in the front from transfering weight and washing the front causing the car to 4 wheel drift earlier than if the car were set up right.

RB can do this to his car and balance the suspension with the throttle, but what happens is it becomes loose when gas is lifted/ his ultimate cornering g's in a balanced throttle drift will be lower than his balanced skidpad 4-wheel drift. This is where you guys aren't realising where every little bit counts.

Edit: back to Hg's problem- its a frontend problem, not a rear end one.

 

ok after reading this matter I now know I will keep as far away from suspension as I can... I'll stick to 1/4... wow I never knew suspension could be THAT technical... sounds dangerous to mess with a stock setting...

 

well that is getting VERY technical with it. most people don't ever get that deep into setting up their suspension.

and there is just as much tech involved in setting up a suspension for 1/4 mile. if you want to get into it, get into it little by little, and start doing thing to enhance what you have.

 

yeah... well I guess our cars are no F1 or stock cars... I personally don't feel safe flooring My bird in a curve, I know it can handles pretty well for a big boat but still... My V6 seemed to hang better in the curves... but this threat is not abotu My car anyway

you guys usually give great advices, minus the b|tching that flies from time to time... keep on the great works... I'll hang in this forum more often since I usually hang in engine and finishing and want to learn more about suspension now

 

Too bad I was gone for this discussion. Anyway, I had the exact problem the original poster "HG" has. Subframe connectors, lowering springs, and really poor traction in first/second gear. LCA relocation brackets fixed it for me. Mine used to push when it was stock, the drop springs made it horrible loose under throttle before the brackets. I can come out of a turn much harder now. All the while running a 1 5/16 solid front bar and 1 inch rear bar. These cars aren't built with a fully adjustable suspension(like a race car). If they were, we could alter ride height to whatever worked the best, as well as any number of other suspension adjustments to fix the problem HG has. I find it hard to believe that adjusting the control arms Back to a level position(screwed up from lowering) is such a bad thing. IMO, the brackets will simply correct a problem created by the lowering springs

 

agood2.8's adive was good at describing the idea he was trying to convay. and he is a very sharp guy from what i have read of his, the diffrence in opinions comes from a diffrence in how we read the problem. i though HGs problem, was the same as you are describing, you aren't really "Loose" what you have, and i think HG has is a traction problem, it just won't bite coming out of the corner, and you loose the back end due to tire spin when you apply throttle.

like i said, i don't think agood2.8 is wrong, in fact by him describing what he did, he showed he understands alot (probably alot more than i do) about suspension theory. but what i disagree with him about is the same thing RB was saying, is that the problem i see is that HG (and youself) can't get any forward bite when you apply the gas.

that is why i gave the advice i did, get the brackets (they are cheap) when you fix the geometry to where it shoudl be back there, and if the car still is tail happy (oversteer problem) then start looking at the front , like adding a larger sway bar, ect to correct what is an oversteer problem.

but of course, that is only my advice, and what i would do if my car did what i THINK hg is describing.

 

Here's what started the whole "argument":

Up near the top: Which is of course completely contrary to all known car behavior, including the very reason those brackets are used in the first place, which is to increase rear end traction; and then all the subsequent chest-beating and name-calling to cover up this blatant over-simplification of what actually happens in the real world, arrived at by over-emphasizing one tiny aspect of car dynamics, namely the geometry of the suspension that causes the rear end to "steer" slightly in corners by way of the control arm angle slightly changing the wheelbase of the car differently on the inside side and the outside side as it moves through its arc, but ignoring the far larger effect, which is weight transfer onto the rear wheels or the lack of it. After all, a car will go alot faster around any kind of a course with turns, if you can get back on the gas sooner as you exit the turns; and the more power a car has, the more of a difference this will make in its lap times; and all of this is so painfully obvious, it's almost humorous to see that it can be overlooked.

And then on top of that, at the end of it all, he sort of admits his mistake, but instead of simply saying "I'm sorry, I see your point", the name-calling just kept on.

It is typical "sports car" enthusiast arrogance that I've seen time and again over the years. People who enjoy that particular aspect of car performance often seem to have the attitude that their pursuit is "superior" to all other forms of motor sports, and that they're so "intellectual" that no mere ordinary mortal can comprehend the mysteries they've tuned in to. We saw plenty of that particular attitude. Which is all BS as far as I'm concerned, it's nothing but geometry. Now I don't claim to be some kind of genius about anything, but I do have a little education along these general lines ( I was a math and physics major) and I currently am employed as an engineer, so I'm accustomed to analytical and quantitative thought, not abuse and ad hominem personal attacks and flame bait on whether my car "appears" to be stock (at least I guess its appearance is some kind of problem) from that terrible pic I posted.

And of course, I'm still waiting to hear how improving rear end traction under power can cause oversteer, when by definition imroving rear end traction produces exactly the opposite effect. I can easily see how changing the control arm angles will change "roll rear steer", but that's not the same thing at all. Maybe we just have a semantics issue here.

But I'm sorry that this post, which started out simply enough and brought up some interesting points that alot of people would like to hear more about, turned into a mudbath. The question often comes up as to whether the reloc brackets affect handling; and it would be great to have an actual discussion of this, the ins and outs of what their effects actually are, without personal attacks. It certainly wasn't my intention to get somebody so worked up over sticking his foot in his mouth that he spouted off like that. Maybe next time I should be more careful how I present the facts, when there's a possiblity of treading on someone's "sports car" ego. Evidently it's a real touchy subject.

 

c'mon guys, the both of you seem to know what you are talking about, true. But it is not by tossing at us technical words that you will impress us, now instead of helping us not only are you b|tching but you are complicating matters. The guy has problems when he doesn't go fast, what the hell does it has to do with cornering and advanced technical suspension? please... just throw your bad words in pm and keep the simple, undertandable stuff to us... let's not fight

 

I admitted I made a mistake? Buddy your lost- I simply explained what LCA relocators can do to oversteer/understeer setup after you suggested that was HG's problem.
Then I stated its a frontend problem his being loose, not a rear end one. If Hg's problem is straight line traction and fishtailing- then he should not have used the term loose- this is a cornering term-" can't hook up" would be the proper traction term for adding LCA relocators

Dewey- tailhappy is loose and is reference towards possible "oversteer" when related to suspension setups not "understeer" like you stated above- just wanted to clarify that for others- probably just a slight oversite on your part

Guys- this is old and were done- everyone else has enough info on actual LCA setup angles pertaining to cornering setups- what I stated above is 100%correct and can be backed up with several different publishings (thats know as "facts" Mr RB )

 

yeah, that is what i get for posting at 6am LOL, i knew what i was talking about, my fingers however, did not.