Sway bar knowledge

[CycloneBob]

I have a Shell Valley Coupe that with high speed maneuvers is showing me some roll. How big of a sway bar has any of you guy's used? and where did ya get it? I'm looking at a 1 1/8" bar from Progress Tech. It's for a miata mx5,and won't take to much to adapt.. Any help out there, Thanks!

[Sydney]

I have an 03' Shell Valley Cobra. back then the Cobra frame and the Coupe frame were almost identical. years ago I installed a solid 15/16" Miata bar from GoMiata.com. It fit perfectly and the handling of the car improved significantly. A few years later I up sized to a tubular 1 1/8" bar and I like the handling even better. The larger bar has a more neutral feel for me and the smaller one has a very slight over steer feel. Adding the front sway bar was one of the best improvements I have made to the car over the years.

[CycloneBob]

I wonder if you could post a couple of pics of how you mounted the bar, and which one it is. The Progress Tech bar I'm looking at (61.1132 front bar), I would mount it from behind. (stronger frame area) I wonder how much your frame may differ from mine.

[Sydney]

Here's my gallery pic. I had made a combination lower radiator/sway bar mount out of some square tubing and bolted it to the front cross member and front bumper supports. The brand of the sway bar is Racing Beat. It is for a 94-97 Miata.

I purchased the hardware to attach the ends of the bar to the lower A-arms from McMaster Carr. It has all been working great for about 10 years now.

[silverback]

we use speedway engineering they have many options. The sway bars come in different lengths and are rated to the lb. based on the arm length used. They are great if you really want to fine tune.

[bobcowan]

Body roll is not necessarily a bad thing. Changing sway bars will change handling characteristics, specifically under and oversteer. If your car is pretty neutral right now, and you add a significantly larger front sway bar, you will most likely develop oversteer.

How Sway Bars Work and Why You Should Care | Speed Academy

If you just want to eliminate body roll, you might want to consider increasing springs rates. Especially if you're getting a lot of nose dive on hard braking.

How's your transient response? On a quick left right left, does it seem to wallow or get tail happy? If it does, that would be another reason to consider better springs.

[bwcobra15]

I'm definitely interested in following this thread as I want to add a front sway bar to my Hurricane build currently underway.

[cycleguy55]

Originally Posted by bobcowan

Body roll is not necessarily a bad thing. Changing sway bars will change handling characteristics, specifically under and oversteer. If your car is pretty neutral right now, and you add a significantly larger front sway bar, you will most likely develop oversteer.

How Sway Bars Work and Why You Should Care | Speed Academy

If you just want to eliminate body roll, you might want to consider increasing springs rates. Especially if you're getting a lot of nose dive on hard braking.

How's your transient response? On a quick left right left, does it seem to wallow or get tail happy? If it does, that would be another reason to consider better springs.

Increasing the size of the front bar or adding one will increase understeer, not oversteer.

To increase understeer: Add or increase the size / stiffness of the front bar, reduce the size / soften or remove the rear bar, or a combination of both.

To increase oversteer: Add or increase the size / stiffness of the rear bar, reduce the size / soften or remove the front bar, or a combination of both.

[CowtownCobra]

A few of us have used a 3/4" 65 Mustang rear swaybar as our front swaybar. I like the way it made the car respond, but I'm a street cruiser not a racer.

[bobcowan]

Originally Posted by cycleguy55

Increasing the size of the front bar or adding one will increase understeer, not oversteer.

To increase understeer: Add or increase the size / stiffness of the front bar, reduce the size / soften or remove the rear bar, or a combination of both.

To increase oversteer: Add or increase the size / stiffness of the rear bar, reduce the size / soften or remove the front bar, or a combination of both.

You are correct. Should have read my own article a little more closely, I guess.

Anyway, the point is, changing the sway bar will change the way the car handles. That's really the whole point. If you're not careful, you could create an evil handling car in certain situations.

Before making any changes, carefully evaluate how the car handles, then - and only then - make the appropriate changes. Re-evaluate the car, and be prepared to make more changes if necessary.

[bwcobra15]

Originally Posted by Sydney

Here's my gallery pic. I had made a combination lower radiator/sway bar mount out of some square tubing and bolted it to the front cross member and front bumper supports. The brand of the sway bar is Racing Beat. It is for a 94-97 Miata.

I purchased the hardware to attach the ends of the bar to the lower A-arms from McMaster Carr. It has all been working great for about 10 years now.

This is just the kind of sway bar I am looking for. My end points are 40" apart, and would like to know if they one would meet my requirements.

[Sydney]

Bob,

The bar measures 39" outside at the ends.

[bwcobra15]

Originally Posted by Sydney

Bob,

The bar measures 39" outside at the ends.

Thats great, thanks!

[FrankR105]

Speedway Eng. Sway Bar and (modified) Arms, mounted in a Lone Star

[Luce]

Nicely done, Frank.

[RallySnake]

I have tried many sway bars in my Arntz. After a near disastrous track day, I have changed the front bar up from 15/16" to a 1 1/8" from Mustangs Plus. I use a 3/4" bar on the rear from a Mercedes. This allows me to corner hard and go into a controlled slide when I want. With the stiff bars, I can run soft springs for comfort on the street and still feel confident in the canyons.