2012 ASM FB6

[rbruno727]

Current Specs Below:


Engine/Drivetrain:
Vittuned
Skunk2 Alpha header
Clutch Delay Valve delete
Hasport rear mount 62A
aFE drop in filter
TracTuff Billet oil cap

Suspension:
Swift Spec R springs
CT Engineering Rear Sway Bar
SiriMoto Phase 2 front Strut Bar
FKX rear Strut Bar

Interior:
RSX type-S shift knob (08U9-2S6M-200B)
superbrightleds.com UV LED lights for map and dome
removed rear seat head rests

Exterior:
OEM splash guards (08P00-TR7-100), sprayed with OEM Alabaster Silver Metallic.
removed pin stripe and edge guards
llumar air 80 windshield tint
SolarGard sides and back window tint

Google Drive for all receipts, manuals and maintenance log.


Purchased with just under 32k miles all stock.

 

[rbruno727]

Replaced shift knob with OEM RSX and removed that funky fresh pin stripe.

 

[rbruno727]

OEM splash guards, a pcv valve, touch up paint and some brake fluid for the CDV delete and SS clutch line install. The PRL line looks nice with the EARLS fittings. The PRL line was recommended over the P2R line because of it's fitment.

 

[Darkout]

Welcome, congrats on the purchase!

 

[webby]

welcome to the forum & congrats on the purchase

 

[rbruno727]

CT Engineering Rear sway bar upgrade is a must. I see a lot of people going for the bigger sway bar (22-24mm vs 19mm) but when it come to sway bars its the geometry of the bar not it's girth that will make the difference. I have it set on the inner holes and it makes a world of difference.

 

[squiggy]

when it come to sway bars its the geometry of the bar not it's girth that will make the difference.
View attachment 49569

I think @Nix may disagree with you on this.

 

[Twitch]

I think @Nix may disagree with you on this.

+1

How is the geometry relevant? The shape of the bar is forced by the frame and design of the car. How is this bar shaped differently than another bar of the same or greater thickness?

The leverage on the inner hole vs the outer hole has more to do with physics than geometry. Your applying leverage at a different point which causes the bar to flex at a different rate. The longer the lever the greater the force. This is where the girth is relevant. When the bar is thicker it will flex less. This lack of flex is what stiffens the suspension.

Of course material will also play a factor as different types of metal flex at different rates.

I will let @Nix correct any errors in my engineering.

 

[Nix]

I apologize for the book:

Everyone is correct to a degree. For the most part there has not been a bar available with an adjustable "leverage" point. Eg: A longer mounting point with multiple holes. Adjustable end links would be the most effective way to finesse the rate of the sway bar over changing the mounting point. Unless you are trying to go beyond the 24mm Progress bar and achieve a ton of oversteer. At that point you would be a track master and not be reading this forum for tips on improving the handling of your Civic.

Both leverage and thickness play a role in the effect a sway bar has on the suspension. The thickness is multiplied by the sum of squares. Upgrading to a larger rear sway bar has been a quick and effective means of creating more oversteer on a car that generally has a ton of understeer. For a cheap amount of money you can effectively improve the handling characteristics of the Civic by using a larger rear sway bar. The small upgrade from 19mm to 22mm results in a 34% increase in rear stiffness. Bam, instant available performance you can feel right away. Its proven, effective, and cheap. It has nothing to do with geometry or lever arms but with simple uprating in the sway bar itself through an increase in size. Keeping the same size bar but changing the geometry of the lever arm will provide the same changes but perhaps not at the same rate. Also, not being able to keep the lever arm perpendicular will not be an improvement in handling which is where adjustable end links once again become an important part of the setup. For most end users, adjustable end links are a constant PITA with noise and the need for a proper corner balance alignment.

Just buying the 22 or 24mm progress rear sway bars and utilizing the stock end links or the solid Moog end links have proven to be a hassle free, cheap, and effective upgrade. Not knocking the CT setup but hey, if it ain't broke, don't try and improve it unless you're an engineer. Also changing to aftermarket suspension setups with different spring rates than stock will have a huge impact on handling and the setup of the sway bars if you are going to start playing with lever arm distances and endlnk lengths. Keeping everything static to a point will help a ton in deterring what changes need to be made to get the car to a balanced handling point.

If you just bang every super stiff part there is out there onto your car is may feel like it handles on rails but isn't actually cornering better than your grannies civic. The suspension is a game of balance. Spring rates, sway bar rates, and tires are a system. So far no one has had any bad effects from a larger rear sway. I doubt using one with a longer lever arm will change much.


Bars with multiple holes are changing the lever arm:
Using a longer lever arm adds preload. Bars with more than one mounting hole add more preload. Adding preload to a sway bar effectively increases its rate or makes it feel larger than it is. It is not as effective as fully upgrading to a larger sway bar. We are talking about changing the rate of the sway bar in orders of magnitude. You could easily achieve the same difference by utilizing adjustable end links instead or a bar with multiple mounting holes to change the rate of the bar. Overall an increase in the thickness of the bar is going to create the kind of change you can feel and use. Adjustable end links and multiple mounting holes are for when you are trying to achieve a certain balance in the car. The setup from the factory favors understeer so badly on the Civics you will not need to lessen the effect of a larger rear bar with a lesser lever arm on the sway bar unless you are a track master. At that point the simplicity of the larger rear sway would be best served by using an adjustable end link and fine tuning from there.


Same effect, different way of going about it. For example you could get grip from wider tires or from a stickier tire compound. Same result, different way of going about it. Hopefully that makes sense.


This is a long answer depending on how much you want to get into the physics of race car handing. I could write you a book on what I've learned but here is a great resource. If you don't understand it you need to keep reading.

http://www.vikingspeedshop.com/the-truth-about-sway-bars/


TL : DR

The larger the change in diameter of the bar the more noticeable the effect vs a longer lever arm "blade" mounting point. Changing the mounting hole effectively changes the rate of the bar. So do adjustable end links. The hole/endlink solution lets you feel like you have a 21.5, or 21.7mm bar instead of a solid 22mm bar. We are talking negligible differences usually. Its big changes vs small changes. Just get a larger rear bar unless you are running race level suspension.


Super TL : DR - Buy the big bar. Don't waste your time on adjustable end links and longer "mounting holes" unless you seriously understand what you are doing. The incremental changes on a street car aren't worth the hassle/worry.

 

[Nix]

How far down the rabbit hole do you want to chase it?

Bundorf analysis: Especially applicable to FWD vehicles

https://en.wikipedia.org/wiki/Bundorf_analysis



The principle cornering compliance terms are the reciprocal weight normalized tire stiffnesses, not "weight transfer" terms. The SAE terms were probably to mean the rigid body self-aligning torque/moment metrics. In terms of values, tires are generally 2.5 to 3.5 deg/g, front aligning torque compliance steer values are .3 to 1.5 deg/g, typical roll steer compliances amount to -.3 to +.6 deg/g. This produces modern cars and trucks with typical front cornering compliance recipes of 3.5 to 6.5 and rear cornering compliances of 1.5 to 4.0 deg/g. The understeers of such vehicles are found to be 1.5 to 4.5 deg/g. This produces acceptable lateral acceleration bandwidths of .8 to 1.3 Hz. i.e. response times of .25 to .45 seconds. The fact is even the Government is involved in handling criteria, from rollover to sine-with-dwell. Anything else in these modern times would simply be unsalable because today's drivers are much more tuned into good vehicle statics and high speed dynamics. BTW: anyone ignoring the force or geometric cornering compliance terms (which is popular in the academic and enthusiast press zones) is never going to have credibility with any manufacturer, from Ferrari to Elio or Tata. A vehicle is very much more than a go-kart on very high pressure tires. Spherical jointed links can have load induced steer. Even your tube framed, carbon fibre, transparent aluminum equipped race cars have managed non-tire cornering compliance.


Buy the bar you like and be sure to note what changed in regards to handling. its very easy to upset a fine handling car into a dump truck that you hate.

 

[rbruno727]

Hell yeah, thanks for the feedback guys. Thanks Nix that is a lot of information to take in. Right now I am pretty satisfied with the CT bar, another reason I went with only a 19mm bar is the 2012 civic si rear sway bar mount brackets are not a thick as the 2014+ because of the OEM 15mm bar size. My car does not see track use, I just wanted to tighten up that sloppy rear end, the body roll was disgusting. Now it is starting to handle more like a Si should.

Always learning...... from: http://www.vikingspeedshop.com/the-truth-about-sway-bars/

 

[Nix]

Exactly. Different ways to go about the same thing. Im glad you like it and it did what you wanted.

 

[Rennmeister]

Hi, I wrote that sway bar article you guys just linked to. I'm glad it helped out. I try to keep a moderation of reading level in the articles so that it's not too much at once.

Can't say that I've EVER been in a thread with Bundorf analysis being discussed, LOL ... I can tell Nix read the manual twice.

Let me know of any changes or comments about the article you might have, and I figured I'd let you know about some others that might help with your build:

Home -- Here's the whole list (Old URL, I'm not a business, just haven't thought of a fun replacement name.)

Basic Alignment Specs - Camber, Caster, and Toe

How Shocks Work - Rebound, Compression, Linear vs Digressive Valving, Twin Tube vs Monotube

Spring Tech - Linear / Progressive / Dual Rate Calculations, Standard to Metric (Lbs. / In. to Kg/mm), and Determining Effective Wheel Rates via Motion Ratios

Braking Components - Brake Pads, Lines, Fluids, Single vs. Two Piece Rotors, Thermal Management (I'm really expanding this article soon with some insider / race tech)

Good luck with your build and you're more than welcome to contact me if you have any questions. I try to keep up with all the forums I am on, but I have a baby on the way, USGP is in 2 weeks, so I'm a bit time short.

FWIW I drive a Honda daily ... an ol' 99' Civic CX with double digit HP and that good Wangan / Autobahn spec gearing all the non-fun Civics got, haha.

 

[squiggy]

Can't say that I've EVER been in a thread with Bundorf analysis being discussed, LOL ... I can tell Nix read the manual twice.

Nix and many others on the board are either engineers or have engineering degrees.

 

[rbruno727]

After a quick test drive I am very pleased with the SiriMoto Strut Bar.

 

[T-Wolf]

What changes were felt with the strut bar?

 

[rbruno727]

What changes were felt with the strut bar?

It reduced the amount of pitch/roll felt on the front end during turn in.
After I upgraded the rear sway bar the front really felt like it had to much body roll, this strut bar took care of that.
If you like suspension upgrades I highly recommend this, the chassis feels much stiffer.

Next upgrade will be a Hasport rear torque mount.

 

[T-Wolf]

It reduced the amount of pitch/roll felt on the front end during turn in.
After I upgraded the rear sway bar the front really felt like it had to much body roll, this strut bar took care of that.
If you like suspension upgrades I highly recommend this, the chassis feels much stiffer.

Next upgrade will be a Hasport rear torque mount.

Ditto on rear engine mount.

 

[Flightmaster127]

Ditto on rear engine mount.

I'll third that. It's really a fantastic upgrade for the price. Really improves the feel of the car.

 

[rbruno727]

Picked up a couple of little things this month, UV LEDs for the inside (to much time in ybor city growing up has left me with a fondness for blacklights) and CorSport Bushings.