What Sway Bars Work Best For You?

[solidONE]

@M0nk3y I kinda expected that response, "it works." But I wanted to see what was the thought behind going with the larger front bar. Is it for the adjustments mainly or is there a preference for charateristics of a stiffer front bar? Thanks for the explanation.

The calculations is to help with part selection. Dialing in the parts to work together is a lot of experimentation and feel. Everyone is a bit different preferences in feel during different parts of the turn. For instance @maregt had 3 different settings he tested. Just from his description I can say I probably wont like his #2 setup with the 6k/8k springs as much compared to #1 or #3, but that's his preference and likely suits his driving best.

I do agree with your thought on spring and damping balance. Though I've found more damping pressure may feel great at higher loads and speeds, but on low load/high frequency stuff you will be compromising. Which obviously not a top priority for your uses. More of a consideration for traction than for comfort. I'm sure there are magical piston valving that can do it all. Like a Ohlins high frequency piston with digressive shimming, or a penske regressive if you have the means and time to dial something like that in, but that way to hardcore and costly. Fancy parts you need fancy money and a fancy amount of time to get right. For now I'm trying to make basic part perform fancy.


The tire wear comment is entirely unrelated, just something I've been trying to troubleshoot and to share my experience with the only modification to the sway bar I've done in the past. Did not have the result I wanted with the 19mm Perrin with OE damper and spring, but I'm trying to talk myself into putting it back in I guess. Maybe there are things I have not tried with them that will work better to my liking.

[steverife]

I don't know if math supports the thought that bar rate is more effective than spring rate in mitigating an unfavorable camber curve.

...but I do know that "too much" spring tends to make the car less predictable and harder to drive on the imperfect surfaces that you often encounter in autocross.

Adjustability is just a bonus, IMO.

[Racecomp Engineering]

Originally Posted by venturaII

Sway bars seem to be underutilized for roll control..

Swaybars have gotten a bad rap online for some reason. The idea of using only the 4 corner springs is really appealing to some but it's just not realistic most of the time.

- Andrew

[venturaII]

Originally Posted by solidONE

@M0nk3y
I do agree with your thought on spring and damping balance. Though I've found more damping pressure may feel great at higher loads and speeds, but on low load/high frequency stuff you will be compromising. Which obviously not a top priority for your uses. More of a consideration for traction than for comfort. I'm sure there are magical piston valving that can do it all. Like a Ohlins high frequency piston with digressive shimming, or a penske regressive if you have the means and time to dial something like that in, but that way to hardcore and costly. Fancy parts you need fancy money and a fancy amount of time to get right. For now I'm trying to make basic part perform fancy.

Load and speed do not correllate when it comes to shock damping, at least not how I believe your using the terms... If you're referring to 'load' as in the suspension itself being loaded in a corner, then that translates to low speed damping on the shock. Hitting a pothole or expansion joint in the road would be more a function of high speed damping, as the suspension reacts immediately and in a far more aggressive manner. My personal feeling is that nearly all aftermarket damping rates tend to get too aggressive on BOTH rates, which results in a sporty feel on smooth tarmac (yay!), but terrible manners over the rough stuff (boo!). I believe the choice is generally made to err on the side of sportier feel, since that's what sells the product, and the market is already expecting the associated result. A three way adjustable shock will have adjustable low and high speed valving on the compression side, and adjustable low speed rebound. High and low speed valving adjustment has been around for 20 years in the street motorcycle world (and even longer offroad...), but for some reason requires a huge investment to purchase in the car world. It does take a little testing to get it dialed in, but once it's there, you generally don't need to touch it again. Even relatively inexpensive dampers work better when you get them dialed in to your specific environment. Silky, compliant action over trashy road surfaces, and firm, tight response over smoother ones. I've used Sachs, Ohlins, and Penske three-ways on my bikes and they were ALL a noticeable improvement, even the relatively inexpensive Sachs. A 4 way would be even nicer, allowing you to really dial in rebound, but it adds an absurd amount of money for the relative improvement.

[Racecomp Engineering]

I think people also get too hung up on the shape of the curve (i.e. is it digressive or not) when I very often see digressive curves that are outrageously stiff in low or high piston speed or both. Yes it's digressive and that's nice, but it's still not very good.

But I could get real off topic here so I'll stop.

- Andrew

[M0nk3y]

Originally Posted by Racecomp Engineering

I think people also get too hung up on the shape of the curve (i.e. is it digressive or not) when I very often see digressive curves that are outrageously stiff in low or high piston speed or both. Yes it's digressive and that's nice, but it's still not very good.

But I could get real off topic here so I'll stop.

- Andrew

Still a great conversation, I wouldn't mind it.

I think trying to revalve an OEM piston @solidONE to perform the way you want you'll be severely underwhelmed at the end result, just IMO YMMV.

Going back to "it just works" convo. My initial shocks and dyno sheets suggested I had fantastic range on my adjustments, when in reality I actually didn't. Just comes with testing and actually playing around.

Since then, I've revalved the shocks, went with a coated piston to reduce initial nose in for low speed stuff and still can satisfy high speed. Can autocross at 60 mph and can smack a curb at Mid-Ohio at 100 mph and car can go "meh"

I'll attach them for reference, but like a typical whp dyno - everyone's input and application is going to be different from how YOU setup the car

[venturaII]

Originally Posted by M0nk3y

Since then, I've revalved the shocks, went with a coated piston to reduce initial nose in for low speed stuff and still can satisfy high speed. Can autocross at 60 mph and can smack a curb at Mid-Ohio at 100 mph and car can go "meh"

What shocks are these dyno charts for?

[M0nk3y]

Originally Posted by venturaII

What shocks are these dyno charts for?

MCS 2 Way External Cans operating at 170 PSI. I think I'm going to play with gas pressure this year

[venturaII]

Originally Posted by M0nk3y

MCS 2 Way External Cans operating at 170 PSI. I think I'm going to play with gas pressure this year

Yow...very nice. Not at all in my budget, but very nice indeed.

[solidONE]

Originally Posted by venturaII

Load and speed do not correllate when it comes to shock damping, at least not how I believe your using the terms... If you're referring to 'load' as in the suspension itself being loaded in a corner, then that translates to low speed damping on the shock. Hitting a pothole or expansion joint in the road would be more a function of high speed damping, as the suspension reacts immediately and in a far more aggressive manner. My personal feeling is that nearly all aftermarket damping rates tend to get too aggressive on BOTH rates, which results in a sporty feel on smooth tarmac (yay!), but terrible manners over the rough stuff (boo!). I believe the choice is generally made to err on the side of sportier feel, since that's what sells the product, and the market is already expecting the associated result. A three way adjustable shock will have adjustable low and high speed valving on the compression side, and adjustable low speed rebound. High and low speed valving adjustment has been around for 20 years in the street motorcycle world (and even longer offroad...), but for some reason requires a huge investment to purchase in the car world. It does take a little testing to get it dialed in, but once it's there, you generally don't need to touch it again. Even relatively inexpensive dampers work better when you get them dialed in to your specific environment. Silky, compliant action over trashy road surfaces, and firm, tight response over smoother ones. I've used Sachs, Ohlins, and Penske three-ways on my bikes and they were ALL a noticeable improvement, even the relatively inexpensive Sachs. A 4 way would be even nicer, allowing you to really dial in rebound, but it adds an absurd amount of money for the relative improvement.

Yeah I forget how things have to be worded perfectly.. lol when I mentioned “high speed” I didn’t mean the shaft stroke I mean driving fast “high speed” and when I mentioned “load and frequency” I’m referring to the damper rod’s movement.

As far as having 2, 3 or even 4 way dampers it’s very nice (and fancy) to be able to fine tune so many points on the damping curve, but I believe a single adjustable or maybe even non adjustable can be valved to “do it all” the non adjustable can be valved to perform similar or maybe even exactly the same way as your 3-way set at your favorite setting.. just without any additional adjustment. I plan on testing this theory.

Sway bars.

[solidONE]

Originally Posted by M0nk3y

MCS 2 Way External Cans operating at 170 PSI. I think I'm going to play with gas pressure this year

On the topic of nitrogen as pressure.. I don’t know if you’ve seen or read fatcatracing’s approach to setting the gas pressure super low. Seems like a recipe for cavitation. 50psi or lower gas pressure.

Maybe we ought to start a new thread.. swaybars

Originally Posted by M0nk3y

Still a great conversation, I wouldn't mind it.

I think trying to revalve an OEM piston @solidONE to perform the way you want you'll be severely underwhelmed at the end result, just IMO YMMV.

Going back to "it just works" convo. My initial shocks and dyno sheets suggested I had fantastic range on my adjustments, when in reality I actually didn't. Just comes with testing and actually playing around.

Since then, I've revalved the shocks, went with a coated piston to reduce initial nose in for low speed stuff and still can satisfy high speed. Can autocross at 60 mph and can smack a curb at Mid-Ohio at 100 mph and car can go "meh"

I'll attach them for reference, but like a typical whp dyno - everyone's input and application is going to be different from how YOU setup the car

I’m not revalving stock shocks. I’ve got a set of inverted front singles and doubles with remote 2-ways out rear. I’ve already buttoned up 3 of the 4 dampers almost ready to send to dyno. I’m experimenting with different weight oils as well so all 4 shocks will be valved differently. After I will stare at the dynographs for a couple days and decide which oil or valving is closer to my goal damping curve then revalve and modify to suit.

Also debating if I should gundrill the mounting stud on top to fit a shader valve. If l run into some extra money to spend I can maybe add a remote can to the front struts.. may have to “borrow” predrilled stud from the BC catalogue. Or just plop down the cash for something shiny. That ohlins high frequency piston looks very interesting and very expensive.

Thanks for sharing your dynos! They are you current dynograph with 170psi gas pressure? I think there is a dyno thread somewhere. I will revive it.

[racingfool]

Originally Posted by Racecomp Engineering

Yes it's digressive and that's nice,

Why is digressive better than linear?

[steverife]

Originally Posted by racingfool

Why is digressive better than linear?

I hope I have this worded right, but...

…the goal is to be able to run a lot of low speed compression that controls roll while keeping the car planted on bumpy surfaces.

A lot of the cheaper options with a linear curve gives you a lot of one of those things and not a lot of the other.

[racingfool]

Pretty confusing =(

The regressive valve is the next logical step

Depending on track layout and vehicle set-up, it is recommended that regressive damping be tried on either compression or rebound.

The Variable Bleed Piston offers the user more versatility than any other piston in our range.
The piston can produce curves like those found on linear, digressive and VDP pistons and offers a very flexible way of controlling bleed.

The Enhanced Linear Flow piston allows the user to get maximum mechanical grip

The Velocity Dependent Piston has the unique ability to be valved as a digressive piston,
with the added versatility of being able to adjust the linear slope after the digressive knee on both compression and rebound.

https://www.penskeshocks.com/shop/?s...ct_cat=pistons