1LE front sway bar & 19mm Z28 rear good combo?

[Hugger3800]

I was wondering if my setup w/ 1LE 32mm front sway bar and 19mm Z28 sway bar is correct and not a dangerous combo without V8 springs up front. I figure that the 32mm is ok up front b/c SLP puts them on the 01-02 Camaro RS as an option. Moreover, since we have the same rear prings as the Z28's then the Z28 19 mm sway should be fine. Is the setup legit? So here is my question should I get SLP Z28 take off springs for the front to counteract the sway bar trade out? Let me know!

[V6Bob]

I mean no disrespect (and I respect very much that you are aware that messing with swaybars might be dangerous), but see my post in reply to "98 z28 sway bars, any different than my 97 camaro v6 sway bars?"

You say: "since we have the same rear springs as the Z28's then the Z28 19 mm sway should be fine"

That's _not_ how swaybars work. The big rear bar on the Z28 is mostly to balance with the Z28's big _front_ springs.

"I figure that the 32mm is ok up front b/c SLP puts them on the 01-02 Camaro RS as an option"

You can't just look at this one piece at a time. What does SLP use in the rear? What springs are they using? All this stuff needs to be matched by a pro. I cringe when I see people slapping this and that together, especially with swaybars.

Once again, no disrespect intended.

[Dominic]

On a stock suspension setup a 32/19 will work well and will decrease the roll rate without inducing much oversteer - for most uses this is adequete [img]smile.gif[/img] I probably wouldn't run the V8 springs unless I had no other option, stiffer isnt always better.

[Hugger3800]

V6Bob

Just want to inform you that SLP puts the 32 mm sway bar in the front and the uses the factory 14mm in the rear on the RS Camaro and GT Firebird. I assume that they know what they are doing when the put these setup together. I believe that they are experts in outfitting f-bodies. My question is, do you believe since they use the 32 mm in the front then since all stock V6 f-bodies have the exact same rear springs as z28's that come stock with the 19mm sway bar will it be ok to add this sway bar to compliment the 32mm in the front. The only adverse sway bar setup I am aware of is the 32mm front and 21 mm rear setup which creates dramitic understeer.

[ December 09, 2002: Message edited by: Hugger3800 ]</p>

[Dominic]

Dramatic Understeer, I thinky ou mean oversteer, and I'd like someone to show me this in my car... :D I can push it hard between 10-80mph and it still understeers at the limit (tires squalling), oversteer must still be throttle induced and its not easy to do!

The SLP suspension designers need to take a few classes in suspension design; in terms of autoX and roadrace performance I can spank an SS with a stock Z28 suspension even on the 16" wheels and stock tires... The bilstein shock valving they use is very oddball and gives a false sense of security by having a "stiffer" ride, only because they upped the bump over HD valving - then for some reason they reduced the lowspeed transition rebound - it just makes the car sloppy.

Just because "blah" does something doesn't make it right...

[ December 09, 2002: Message edited by: Dominic ]</p>

[Hugger3800]

Dominic

So what your saying that this combo is NOT dangerous and it does give suppier handling over the crappy stock setup. I've had this setup done for a week and I love it however, I decided upon the combo by myself so I was alittle unsure of the results. Any thing else you recommend to tighten up the steering feel?

[V6Bob]

"Just want to inform you that SLp puts the 32 mm sway bar in the front and the uses the factory 14mm [should be 15?] in the rear on the RS Camaro and GT Firebird."

Thanks. I've often thought this might be a good setup for everyone except serious autocross competitors. And maybe even for them. Sam Strano used 35/19s on V8 springs on his Pro Solo National Champion car, so maybe 32/15s on V6 springs would be good. The 32 front bar will dramatically reduce roll and increase steering response. The car will feel great. The increase in understeer will be small, because of improved camber control. The rear bar does very little to reduce roll.

"I assume that they know what they are doing when the put these setup together. I believe that they are experts in outfitting f-bodies."

More than anyone you're likely to meet on the Net unless their last name is Strano :D .

"My question is, do you believe since they use the 32 mm in the front then since all stock V6 f-bodies have the exact same rear springs as z28's that come stock with the 19mm sway bar will it be ok to add this sway bar to compliment the 32mm in the front."

Once again, the rear bar and the rear spring are not meant to match each other. That's not how swaybars work. The _rear_ bar is set to match the _front_ spring and bar. That's why V6s have small rear bars, to match the soft front springs. GM didn't give gave the V6s small rear bars to screw up the handling. Believe me, they're doing the right thing. They also know something about setting up f-bodies.

"The only adverse sway bar setup I am aware of is the 32mm front and 21 mm rear setup which creates dramitic understeer[should be oversteer?]."

There are tons of bad swaybars being sold out there. It would be a very unusual setup that would use a 25mm rear, but at least two manufacturers sell them.

Dominic and I disagree on this one.

[ December 09, 2002: Message edited by: V6Bob ]

[ December 09, 2002: Message edited by: V6Bob ]</p>

[FirebirdGT]

<blockquote>quote:</font><hr>Originally posted by Hugger3800:
V6Bob

Just want to inform you that SLp puts the 32 mm sway bar in the front and the uses the factory 14mm in the rear on the RS Camaro and GT Firebird. <hr></blockquote>


Sorry WRONG.

SLP uses a 32mm in the front and 19mm rear, with the stock springs of 225 front, 115 rear. This is the 93-97 front and 98+ rear rates.

Stock rates are 93-97, 225/95 and 98+ 257/115


http://www.hoodscoop.com/

[ December 09, 2002: Message edited by: FirebirdGT ]</p>

[F1GT]

<blockquote>quote:</font><hr>Originally posted by V6Bob:
[QBOnce again, the rear bar and the rear spring are not meant to match each other. That's not how swaybars work. The _rear_ bar is set to match the _front_ spring and bar. That's why V6s have small rear bars, to match the soft front springs. GM didn't give gave the V6s small rear bars to screw up the handling. Believe me, they're doing the right thing. They also know something about setting up f-bodies.

[/QB]<hr></blockquote>

The rear bar is set to match the front SPRINGS and front BAR?
If that is true, then what about the SS/WS6 trim F-Cars?? The springs went up to 360lbs/in and 32mm sways, yet the rear bar stays at 19mm.

The SS/WS6 however did come with slightly higher rate rear progressive springs.

FRONT/REAR:
93-97 V6: 223lbs/in 95.4lbs/in
98-00 V6: 257lbs/in 114lbs/in
93-00 V8: 292lbs/in 114lbs/in
1LE/WS6 : 360lbs/in 130-170lbs/in


What about 32mm fronts and 17mm rear??
28/15=1.87
32/17=1.88
32/19=1.68

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[V6Bob]

"The rear bar is set to match the front SPRINGS and front BAR?"

A little oversimplified, but basically true. A key thing is the balance of roll resistance, front to rear.

The SS data you quote makes sense, if you look at ratios or percentage increase. The fronts increase by 360/292 = 1.23 or 23% increase. The progressive backs are complicated, but lets oversimplify and use the average. The backs increase by 150/114 = 1.32 or 32%. Relative to the rears the fronts are softer, so it needs either a smaller rear bar or a bigger front. If you consider a hard cornering situation, the progressive rear spring may be even stiffer. Honest, GM knows what they are doing.

Much more so than the guys who sell 32/21s to V6 owners. These supposed "1LE" bars were only used by GM on about 25 cars intended specifically for racing before GM decided they were a bad idea and went to 32/19. All this on cars with relatively stiff front springs. None of the really fast guys use such a large rear bar, except with very stiff front springs.

"SLP uses a 32mm in the front and 19mm rear, with the stock springs of 225 front, 115 rear. This is the 93-97 front and 98+ rear rates."

Whew. I think Dominic may be right about SLP. That setup would have as much oversteer as the 32/21s on stock 98+ V6 springs.

Bottom line. Messing with springs and bars is tricky. You can easily screw up the handling. I like Dominics advice in the "suspension upgrade" thread. If you modify your car, first, chassis stiffening, then premium shocks. I would add tires. The result will likely outhandle many cars where people have messed with springs and bars.

[F1GT]

<blockquote>quote:</font><hr>Originally posted by V6Bob:

Honest, GM knows what they are doing.

Much more so than the guys who sell 32/21s to V6 owners. These supposed "1LE" bars were only used by GM on about 25 cars intended specifically for racing before GM decided they were a bad idea and went to 32/19. All this on cars with relatively stiff front springs. None of the really fast guys use such a large rear bar, except with very stiff front springs.

"SLP uses a 32mm in the front and 19mm rear, with the stock springs of 225 front, 115 rear. This is the 93-97 front and 98+ rear rates."

Whew. I think Dominic may be right about SLP. That setup would have as much oversteer as the 32/21s on stock 98+ V6 springs.
<hr></blockquote>


I have absolutely no doubt at all, that GM does indeed know what they are doing. I have never question their know-how. Thanks for the clarification.
But, as you know, people associate "Good Handling" with flat body-roll. That's why people want to do bars and businesses sell to that. Everyone who sits in my car tells me I have a lot of body-roll, and consider it a sloppy handler. Not to mention that it makes the car "look" bulkier/heavier than it already is when the car rolls around the corners.

<blockquote>quote:</font><hr>
Bottom line. Messing with springs and bars is tricky. You can easily screw up the handling. I like Dominics advice in the "suspension upgrade" thread. If you modify your car, first, chassis stiffening, then premium shocks. I would add tires. The result will likely outhandle many cars where people have messed with springs and bars.<hr></blockquote>

Why is it OK to just upgrade shocks, WITHOUT springs. But when you upgrade springs, you have to do shocks??
I can imagine how if you do stiffer/lower springs it is going to bounce harder than the stock springs and the stock shocks have a hard time damping it. But if you upgrade the shocks, it's made to handle stiffer rides, so the "soft" springs are a piece-of-cake to it?? Am I on the right track???
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[V6Bob]

"I can imagine how if you do stiffer/lower springs it is going to bounce harder than the stock springs and the stock shocks have a hard time damping it. But if you upgrade the shocks, it's made to handle stiffer rides, so the "soft" springs are a piece-of-cake to it?? Am I on the right track???"

I'm no expert, but I think it's partly that. And partly that stock shocks are pretty simple. Better shocks are not just stiffer, they damp better (more appropriately) with all the different things and different forces; slow speed motions due to roll, higher speed motions due to bumps, etc.

[Dominic]

An antiroll bar is nothing more than a torsion spring. The larger the bar, the less the car wants to roll front or rear, which gives the car less weight transfer, better camber holding capabilities, and more grip. Increasing the front bar usually results in an increase of front grip to a point, increasing the rear bar usually results in an increase of rear grip... again to a point.

You can only apply only so much force, and the car will only want to roll so much, in a given corner. On a stock swaybar setup for example I could take a poorly banked 35mph interstate corkscrew ramp at 70mph and bottom out my suspension - on the same suspension with the 32/21 setup at even 75mph (tires not squalling yet) the suspension is not bottomed out and still has travel to allow for movement over small ruts in the road...

By increasing the swaybars past the critical size you continually reduce body roll, however if the car can't roll you reduce suspension effectiveness and the ability to use corner braking and weight transfer to your advantage and it'll make the car outright slower.

I daily drive my 32/21 setup, on stock tires with a stock suspension, and I have no complaints. Furthermore I autocross this setup on occasion and it works far better than stock without problems oversteering. When I first installed my setup I did the front bar, then the rear, so I could see what made the most difference and how it affected cornering.

I setup a series of cones spaced out in my neightborhood that I could go through, with aggressive driving, at about 40mph without problems. It was enough to induce body roll quite a bit and was challanging but I had enough space to recover from a problem if I went out of control [img]smile.gif[/img]

Installed my 32mm front bar after doing the stock run, the cornering was slightly more comfortable but the rear just slung all out of check. Everytime I went through the cones the nose would go where it needed and the rear was just *sloppy* feeling. In disgust at how little the 32mm front did, I added the 21mm rear... immediate difference!

With both the 32/21 I could control the car effortlessly through the cones without suspension bottoming and the use of throttle to place the rear became a lot easier for me.

Maybe its a bad setup for some people, but not for me. I can easily autocross this setup, no oversteer problems. The 21mm bar immedately puts me in ESP, but hell so does the whisper lid! I have no problems recommending a 32/19 setup for anyone, its perfectly safe.

Do what you want, thats my say in the matter.

[V6Bob]

Every time I get into these discussions, I see much bad info. And when I try to correct it, I worry someone will take it personally. So, this is _not_ personal, it's just information.

"The larger the bar, the less the car wants to roll front or rear, which gives the car less weight transfer"
"increasing the rear bar usually results in an increase of rear grip"

These are wrong. Increasing a bar _increases_ weight transfer to the outside wheel at that end of the car and therefore increasing the rear bar decreases rear grip. Any book on handling and many websites will tell you that. Herb Adams, "Chassis Engineering" has the clearest explanation I've seen, with tables of numbers illustrating the weight transfer. http://www.grassrootsmotorsports.com/swaybars.html is a decent website.

The front is slightly different, because of improved camber control. Weight transfer is generally more important and a bigger front bar will still almost always reduce front grip, but the effect may be smaller than one would think.

The reason I post so much on swaybars is that I see people changing them with little information or bad information. The results can feel good in normal driving, but can get you in serious trouble in an emergency situation, especially in wet weather. Swaybars affect handling powerfully and it's easy to go wrong.

[ December 11, 2002: Message edited by: V6Bob ]</p>

[F1GT]

Hey Bob, what about Hugger3800 and his 32/19 set up?

32mm will be 71% stiffer than 28mm.
19mm will be 157% stiffer than 15mm.

Won't he be better off with 17mm in the back??
17mm will be 65% stiffer than 15mm.

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