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View Full Version : 68 rear sway bar, no good?



mosaic68
04-10-2005, 06:36 PM
hey guys,
just searching through some of the older threads and noticed some advice against rear sway bars in the 1st gen. F-bodies.

Can anyone explain this? I bought both front and rear hotchkis kits, and if I don't need the rear, I'll take it back and save $300+!!!!!

Currently, I have a pair of multi leaf spring with a 12 bolt and air shocks.

thanks!

Bill

Stu Seitz
04-10-2005, 06:56 PM
I think it's all depends on the type of springs and bushings in the back. I'm running del-al-lum bushing with cat-5 springs and GW said I didn't need it probalie b/c of my solid bushings.

baz67
04-10-2005, 07:47 PM
Bill, if you have not read this please do so. There is some great tech on why it is not advised to run a rear bar in a first get.

Joelean is correct in the spring rate assumption. His cat-5 springs have a higher rate than stock so that adds more roll resistance. If you stiffen up the rear too much than you will get too fast of weight transfer and create oversteer.

If you have stock springs than a rear bar can help. When you upgrade to a higher rate, like the DSE, GW or Hotchkis a rear bar is not needed.

derekf
04-11-2005, 04:02 AM
Brian, was there supposed to be a link there?

mosaic68
04-11-2005, 04:04 AM
OK. so I have stock springs all around, poly bushings, rebuilt it all myself, not really into the idea of ripping into it again, at least right now. Will the Hotchkis rear sway I purchased get me even close to what you guys are accomplishing?

baz67
04-11-2005, 07:48 AM
Thanks Derek. I spent the time getting the link and then forgot to paste it. Doh!
Try this https://www.pro-touring.com/forum/showthread.php?t=205.

Mosaic~ It is your time, but I would return the rear bar and install a new set of springs. Like the ones from Hotchkis, DSE or GW.

Steve1968LS2
04-11-2005, 08:46 AM
Because it is possible to have the back of your car "overly stiff".. with modified leafs and poly bushings I doubt a rear sway would help and would most likely hurt..

I see a tech article in this somewhere :)

JLM
04-11-2005, 09:28 AM
Ok so I just got done reading that entire 101 on rear suspension.

There's a few things that I'm still wondering about. I understand how a leaf spring would act as a sway bar based on how it was originally designed. By that stand point with proper spring rates and shock valving you would not need the rear bar. However some of the spring rates discussed are a little on the stiff side. For a race car on a smooth track that's fine. However (correct me if I'm wrong here) when you have high spring rates your tires tend to "skip" over rough surfaces which can be bad if you are driving aggressively on lets say a mountain road that's not ideal conditions. Not to mention ride quality would suffer.

Wouldn't then a soft spring/big bar setup be the best compromise? From my experiance with mustangs this tends to be the prefered setup once roll center issues in the front, and the horrible design of the UCA/LCA in the back is addressed.

I'm currently researching suspension for my 69 Firebird and it's driving me nuts. I'm looking at doing a Hotchkis TVS but I'm now wondering about the sway bar. I may not need it. I guess I will start with the front suspension and a new set of leafs in the back. If I'm pushing badly I can always add the sway bar.

Finally I haev NO CLUE about shock and valve tuning. I'm assuming I'm giong to need a quality adjustable shock for the front and rear. Which shocks are preferred by your guys?

mosaic68
04-11-2005, 10:25 AM
After reading the link, I realized I neglected to mention something very important: I have a set of traction bars. Would they decrease further the need for a sway bar (since they 'preload' the leafs?)?

chicane67
04-11-2005, 02:23 PM
I say dont run either the stay-bar or the traction bars.... and get a proper leaf spring under the chassis. Traction bars are no help in a chassis that turns a corner...