Anti-roll or Sway bar survey

[1 tuff z]

thought i'd post this informal survey to get an idea of what my z brethren are doing with their z cars. this is for those of you-who have a z that works a double shift - street and track. i'm looking to get an idea of the following; bar size, manufacturer [if you remember], rear bar type [front or rear mount] and if you don't run a rear bar simply a N would suffice. finally, your thoughts on how your z handles-understeer, neutral or oversteer [as relating to; low, medium and high speed corners].

 

thanks, in advance!

 

front bar size/brand

 

rear bar size [f/r mount]/brand

[1 tuff z]

duh, forgot to post what my z is running.

 

front-1", suspension techniques w/msa adj end links

 

rear-7/8", front mount [stock location], brand unknown, w/msa adj end links

 

low speed understeer to a mid-hi speed [slight] oversteer. more body roll than i'd like.

 

will be updating the alignment based on john c's sticky as a starting point.

[johnc]

At various times I ran:

 

1. Suspension Techniques 25mm fromt and 19mm rear.

2. Nissan Competition 23mm front and ST 19mm rear.

3. ST 27mm front and 22mm rear.

4. Custom 25mm front and 16mm rear.

[JMortensen]

Balance in handling is the result of an accumulation of many different suspension factors. A lot of what you're asking about (oversteer or understeer with a given bar combination) might have more to do with spring rates or caster settings or toe settings. What's more, I always felt like I was fighting a push in my car but other people drove it and thought it was tail happy. I think you're oversimplifying the matter trying to narrow balance to just sway bars.

 

To answer your question though, I ran the 25/22 MSA combo for a 240Z. The bar was bound on the frame very badly in the rear. I thought it understeered.

[blueovalz]

Depending on other factors, I've used a combination of 1" front 3/4" rear, but the current set-up has a 1" front and no rear. The rear springs are 17% stiffer than the front are 225/265.

[buZy]

i agree with Jon. im running the st 1 front 34 rear. understeer or oversteer depends on many more factors. the bigeest diff the bars made was the car tracks straight at higher speeds above 100. the car is loose on low speed sharp turns. if pushed in the same corner harder then becomes tight. so there is a full slide balance point somewhere where as to lift of the throttle to quick the car will spin. good enough for me. on the street i dont want to twist it any further.

[janaka]

My suspension is the following:

 

KYB GR-2 struts, front and rear.

MSA Sport Performance Springs.

MSA sway bars- 1 inch front, 7/8 inch rear.

Solid rear strut brace.

Energy Suspension polyurethane master bushing kit.

 

I personally like the way it handles, nice and flat through corners and very responsive. most people are surprised with how well the car handles for its age (most don't realize that most of the car is new...lol)

[auxilary]

front: msa 1" , standard poly bushings

rear: suspension technique 3/4", rear mount (behind the diff)

[LLave]

At various times I ran:

 

1. Suspension Techniques 25mm fromt and 19mm rear.

2. Nissan Competition 23mm front and ST 19mm rear.

3. ST 27mm front and 22mm rear.

4. Custom 25mm front and 16mm rear.

 

How did you like each of those?

[Zmanco]

Front: 1" MSA

Rear: 7/8" MSA mounted in front of rear axle using factory mounts (my 73 had them even though no bar)

Springs: Tokico red

Struts: Illumina

Front adjustable camber bushings for lower control arms

Camber: Front: -0.6, Rear: -1.5

Power brute LSD

 

For street driving, the car's cornering limits are too high to find without risking my license and others' safety. On the track in 2nd gear it is very neutral - I'm at altitude and can almost rotate the car with gas pedal (I think it would be easy at sea level). On the track in 3rd, on the gas there is still a small push from the LSD locking up, and when I lift, the expected looseness is there, but not so bad that it has scared me yet, at least too much

 

So overall, it's pretty balanced with mild understeer. A little more negative camber in the front is next on my list.

[johnc]

How did you like each of those?

 

Each was fine for the particular track and event I was running. I sometimes switched out the ARBs between sessions at the track to adjust the car. I did less of that once I got the Penskes installed. Low speed compression and rebound valving takes care of a lot of the things an ARB does without reducing the independence of the suspension. I finally settled on a 23mm front and 16mm rear ARB and used the shock adjustments to fine tune.

[RTz]

I've played with some of the bars listed, and even a couple homemade jobs.

 

For my purposes, LT1 powered autocross car, I like the stiff spring/small bar approach.

 

Controlling pitch has been a big factor in improving times. Once the springs do that, I've found less dependancy on the bar's. In fact, the bars just hinder compliance and especially corner exit bite (rear bar). As JohnC mentioned, shocks play a significant role in making this viable.

 

I ran without a rear bar as much as possible, but Eugene has some really tight courses (I think they're world famous for it ) and I was never able to fully compensate elsewhere. A stock rear bar is about all I can stand.

 

I've also had good success with this strategy on other cars.

[Zmanco]

Controlling pitch has been a big factor in improving times. Once the springs do that, I've found less dependancy on the bar's. In fact, the bars just hinder compliance and especially corner exit bite (rear bar). As JohnC mentioned, shocks play a significant role in making this viable.

 

I finally settled on a 23mm front and 16mm rear ARB and used the shock adjustments to fine tune.

 

When I read John's comments I was thinking the same thing: that as you are able to go with stiffer springs, you can also go with softer bars (kind of like how the more you get the suspension set up correctly, the lower air pressure you can run in the tires).

 

What I'm wondering is how to balance this move to stiffer springs against keeping the car drivable on the street. Is it safe to say that by the time you have spring rates high enough so that the bars don't need to be as stiff, that you are on the edge (or perhaps past) where the car is still streetable?

[JMortensen]

What I'm wondering is how to balance this move to stiffer springs against keeping the car drivable on the street. Is it safe to say that by the time you have spring rates high enough so that the bars don't need to be as stiff, that you are on the edge (or perhaps past) where the car is still streetable?

Depends on how sticky the tires are. If you're running really sticky tires, you'll have more body roll. To counter that you need stiffer springs or sway bars or both. You can have a well balanced car that is really fun to drive but has street tires on it, but put sticky tires on that car and suddenly you have excessive roll.

[johnc]

What I'm wondering is how to balance this move to stiffer springs against keeping the car drivable on the street. Is it safe to say that by the time you have spring rates high enough so that the bars don't need to be as stiff, that you are on the edge (or perhaps past) where the car is still streetable?

 

Street cars use the big ARB, small spring paradigm. Race cars have almost all moved to the big spring, small ARB paradigm unless rules get in the way. A serious racing 240Z runs spring rates 275 lb. in. and above. FYI... my definition of a race car is pretty hard core - you wear a helmet every time you drive it. Anything else is a street car pretending to be a race car.

[RTz]

What I'm wondering is how to balance this move to stiffer springs against keeping the car drivable on the street. Is it safe to say that by the time you have spring rates high enough so that the bars don't need to be as stiff, that you are on the edge (or perhaps past) where the car is still streetable?

 

Adding to the others' comments, there's a lot more that contributes to ride quality/harshness than springs. Shocks, tire construction/profile, unsprung weight (especially as you get stiffer), bushings, etc. But don't forget the most important factor... you. Everyone, even amongst the hard-core, has dissimilar tolerance levels. You'll just have to experiment and decide for yourself what's 'streetable'.

[cygnusx1]

F 1-1/8"

R 7/8"

Suspension Techniques.

 

I feel the car pushes at low speed turn-in, so I run the front endlinks loosened a tad to help. In high speed turns it handles fine. At Limerock I was running away from most cars in the turns. The springs are unknown rate Tokico 1" drops. On the highway I feel like I need more strut over the large dips in the road. I run the Illuminas on 2 and 3 but should probably go higher for all out performance.

 

I would like to try a smaller set of bars someday to compare.

[260DET]

Street cars use the big ARB, small spring paradigm. Race cars have almost all moved to the big spring, small ARB paradigm unless rules get in the way. A serious racing 240Z runs spring rates 275 lb. in. and above. FYI... my definition of a race car is pretty hard core - you wear a helmet every time you drive it. Anything else is a street car pretending to be a race car.

 

Yeh, as a road/circuit car the project S130 will wear the heaviest springs it can handle on the road, starting with 400F/300R, thats the wheel rate too. The bigger the ARB the more weight transfer to the outside wheel, not good in racing.

 

From memory the road/circuit S30 ended up with 250F/275R springs, 25F/14R ARB's, somwhere around there anyway.

[Brad-ManQ45]

I think that posting specs on suspension setup w/o tire info is a bit worthless...

 

UNLESS you run the same size all around.

 

Still, choice of aspect ratio makes a bit of difference in feel, so I would think that at least tire sizes F/R should be included...

[ZR8ED]

Well my car may not be applicable, but i'll post just because...

 

78 280Z

VG30ET (that is the big difference)

 

I used to run a heavily modifed L28.

 

Tokico bars front and back

 

Front 1.25"

Rear 1"

 

Tokico shocks/chevette springs.

 

235/45/17's front and 315/35/17's out back Yoki AVS Sports.

 

Car was very neutral on the track. (comments from autocross drivers with 20 times my experience) 225/50/16 front and 245/45/16 BFG KDW's

 

When I went to the VG30ET motor, I had to swap out the urethane endlink bushings in the front for rubber to get rid of the push. Was very neutral and controlable after that.

 

I really want to upgrade the springs and go to smaller bars.

 

Scott