Honda CR-Z Hybrid Car Forums banner
21 - 40 of 69 Posts

·
Capt'n Jack
Joined
·
9,498 Posts
:popcorn: Just checking in.. Interesting..
 

·
Registered
Joined
·
35 Posts
In theory yes. I questioned the benefit and did some searching (after my original post in this thread)...the results of my searching are in the link I posted. We know that a driver's butt dyno is very inaccurate...I'm just questioning the sensational claims after adding the RSB. If there is no measurable benefit after adding the RSB (lap times, slalom, G's, etc) then one has to conclude that any perceived improvement is in the driver's head. Of course there is the possibility that any of these performance measures might be DECREASED...as of now, I haven't seen any actual data to say one way or the other.

I have to admit that this mod is now on my "to do" list.
 

·
Registered
Joined
·
2,515 Posts
i have nothing else to add to your fitfreak thread. the technical information is all there.

i can bend the rear torsion beam - i know because when installing springs etc i just pushed down to loosen things when i needed some space.

if your argument is it doesnt make a HUGE difference I'd say youre correct. You dont notice the bar at all when you are driving in a straight line. When turning you will notice decreased steering effort at low speed. Moderate speed the car rotates more in turns (car more prone to oversteer than it is from the factory). High speed and twitch maneuvers become more "dangerous" due to the potential of more oversteer (ex: quick lane changes, avoiding things in the road)

I dont think anyone was trying to sensationalize which seems to be how you read the posts.
 

·
Registered
Joined
·
35 Posts
north bridge said:
I dont think anyone was trying to sensationalize which seems to be how you read the posts.
I just read alot of posts on FitFreak when these bars were first coming out...people were sayin things like "best suspension mod" and "start with a RSB" and "car now rotates in the corners."
 

·
Registered
Joined
·
283 Posts
Ok I'll explain because you seem to be slightly misinformed. Ok so you said the following:

"If the theory is that the giant rear trailing arm twists during aggressive cornering...then somebody please exaplain how attaching a thin little sway bar to a MASSIVE sway bar (the rear trailing arm) is going to do anything noticeable?"

Here's the facts. First we'll talk about this "giant rear trailing arm". It is actually frail and will definetly twist under load.

And if you think a 19mm solid rod is thin and little, please make video on youtube of a superman demo and try to bend it. The progress rear sway alot stronger than you think.

By adding it, you would be improving on Hondas flawed design. I guess progress decided to make it for the hell of it.

One thing I know is that it will definetly tighten up the rear of your car resulting in better turning up front. I know all this because I had all the same questions as everyone here. But being a mechanical person I did my legwork and spent about 30 minutes on the phone with progress R&D department and got all the answers I needed. I can't wait until I finally install it!
I don't actually see any facts here, other than something about 19mm...
 

·
Registered
Joined
·
1,199 Posts
Discussion Starter · #29 ·
I don't actually see any facts here, other than something about 19mm...
Ok. 2 key facts from progress when I called.

1. The rsb is 19mm solid (aka not hollow)

2. Adding this will reduce understeer resulting in better turn-in. The side effect of that will be increased chance of oversteer if turns are entered at higher speeds. Some people like that because drifting is fun!!! :lol:
 

·
Registered
Joined
·
1,962 Posts
lol e-thugs. smh. heres my .02 cents, i sway bar may it be on any application is an improvement, why? bc a sways bars ultimate purpose is to give the inner portion of the tire more grip. theres tons of physics involved in a properly tuned anti-roll bar. ideally a adjustable anti-sway bar would be full of win, but with the cr-z any form of sway bar is a plus lol and a huge improvement.
 

·
Registered
Joined
·
35 Posts
lol e-thugs. smh. heres my .02 cents, i sway bar may it be on any application is an improvement, why? bc a sways bars ultimate purpose is to give the inner portion of the tire more grip. theres tons of physics involved in a properly tuned anti-roll bar. ideally a adjustable anti-sway bar would be full of win, but with the cr-z any form of sway bar is a plus lol and a huge improvement.
:face palm:

Sway bars are grip reducers. That is how they induce oversteer when properly tuned.

Actually, a sway bar's ultimate purpose is to reduce chassis roll. And I disagree that a swaybar "be it on any application is an improvement." That is just so incredibly incorrect. Read more on suspension tuning. Start here:
http://en.wikipedia.org/wiki/Sway_bar
 

·
Registered
Joined
·
2,515 Posts
:face palm:

Sway bars are grip reducers. That is how they induce oversteer when properly tuned.

Actually, a sway bar's ultimate purpose is to reduce chassis roll. And I disagree that a swaybar "be it on any application is an improvement." That is just so incredibly incorrect. Read more on suspension tuning. Star here:
Sway bar - Wikipedia, the free encyclopedia
what?

how does this make sense (legit question). In a front drive car you turn: the front wheels turns in, the opposite rear wheel (relative to the direction turned) wants to lift. A sway bar reduces roll and keeps the wheel that wants to lift down thus leading to more grip at the rear. Did I miss something?
 

·
Registered
Joined
·
35 Posts
what?

how does this make sense (legit question). In a front drive car you turn: the front wheels turns in, the opposite rear wheel (relative to the direction turned) wants to lift. A sway bar reduces roll and keeps the wheel that wants to lift down thus leading to more grip at the rear. Did I miss something?
A sway bar helps the suspension work in concert...so if the outside spring compresses during body roll, the sway bars makes the inner spring compress as well. If the inner spring compresses, there is less grip on the inner wheel (less downward force) and BY REDUCING GRIP, understeer is reduced. If grip is reduced quickly and dramatically, this can result in snap oversteer.

I posted all of this information before in the "CRZ/Fit suspension design" thread. I still can't understand why that thread wasn't made a sticky.:dunno:
 

·
Registered
Joined
·
2,515 Posts
A sway bar helps the suspension work in concert...so if the outside spring compresses during body roll, the sway bars makes the inner spring compress as well. If the inner spring compresses, there is less grip on the inner wheel and BY REDUCING GRIP, understeer is reduced. If grip is reduced quickly and dramatically, this can result in snap oversteer.

I posted all of this information before in the "CRZ/Fit suspension design" thread. I still can't understand why that thread wasn't made a sticky.:dunno:
for whatever reason threads here dont get stickied often.

anyway, that made some sense but overall grip isnt "reduced" or else the car would slide. When grip on the inner wheel is "reduced" it is reallocated by way of the bar to the outer wheel that would be lifting / in need of more grip to help the car rotate (which is why understeer is lessened).
 

·
Registered
Joined
·
1,283 Posts
BnD is correct in how a rsb works. It reduces understeer in hard cornering by letting the inside wheel lift and overloading the outside wheel causing it to slip. Unless I've missunderstood something ofc.
 

·
Registered
Joined
·
35 Posts
for whatever reason threads here dont get stickied often.

anyway, that made some sense but overall grip isnt "reduced" or else the car would slide. When grip on the inner wheel is "reduced" it is reallocated by way of the bar to the outer wheel that would be lifting / in need of more grip to help the car rotate (which is why understeer is lessened).
Incorrect. Grip is reduced from two tires to one tire (or 1.5 tires or some factor in between) during cornering. If grip was simply reallocated then the car would still understeer.

How exactly do you think the rear rotates if not from sliding? <-- legitimate question.

There are not enough people on this forum who actually understand suspensions and actually tune them. I have to go to work and unfortunately can't continue this discussion. I suggest you read the links I provided in this thread above and in the suspension thread I made awhile back.
 

·
Registered
Joined
·
2,515 Posts
Incorrect. Grip is reduced from two tires to one tire (or 1.5 tires or some factor in between) during cornering. If grip was simply reallocated then the car would still understeer.

How exactly do you think the rear rotates if not from sliding? <-- legitimate question.

There are not enough people on this forum who actually understand suspensions and actually tune them. I have to go to work and unfortunately can't continue this discussion. I suggest you read the links I provided in this thread above and in the suspension thread I made awhile back.
I read the link you posted. Still didnt see what Im asking. This thread will be ehre when you get back from work - lol, im sure someone here understands this fully. I know dont have complete grasp but im trying to figure it out.


To answer your question
I thought the rear rotated by having more grip due to decreased roll. Here were my thoughts: a stiff coilover reduces roll partly because it requires more force to manipulate the suspension up and down resulting in less compression during turns. When you turn with a stiffer suspension the car rolls less, keeps more tire on the ground and turns "better" right? I thought that was due to the extra grip provided by decreased roll and more tire on the ground (oversimplification but you get the idea).

As for the bar, decreased roll I thought had the same effect. The bar cant manipulate the suspension when not under load. When the rear inside corner is under load I though that the bar functioned by distributing the load more evenly to the other side. I never thought the rear needed less grip to "slide" around.

Apparently im wrong. I'll be looking for more information - anyone care to throw in another explanation?
 

·
Registered
Joined
·
35 Posts
I read the link you posted. Still didnt see what Im asking. This thread will be ehre when you get back from work - lol, im sure someone here understands this fully. I know dont have complete grasp but im trying to figure it out.


To answer your question
I thought the rear rotated by having more grip due to decreased roll. Here were my thoughts: a stiff coilover reduces roll partly because it requires more force to manipulate the suspension up and down resulting in less compression during turns. When you turn with a stiffer suspension the car rolls less, keeps more tire on the ground and turns "better" right? I thought that was due to the extra grip provided by decreased roll and more tire on the ground (oversimplification but you get the idea).

As for the bar, decreased roll I thought had the same effect. The bar cant manipulate the suspension when not under load. When the rear inside corner is under load I though that the bar functioned by distributing the load more evenly to the other side. I never thought the rear needed less grip to "slide" around.

Apparently im wrong. I'll be looking for more information - anyone care to throw in another explanation?

I will give a more complete explanation when I can...but hopefully this will help you to understand.


The large arrow is the compressive force on the suspension during turns. This is the OUTSIDE wheel. The small arrow is the corresponding upward force applied by RSB on the inside wheel.

I think you are confusing yourself by concentrating on the inside wheel...the inside wheel is not experiencing the load in a corner. What happens in a turn is the weight of the vehicle is transferred to the OUTSIDE wheel (inertia, body roll, etc)....this force compresses the outside shock. The RSB, helping the suspension to work in concert, applies a corresponding upward force to the inside wheel's shock...this upward force reduces grip (because there is less downward force exerted by the inside rear tire) and leaves the outside tire to do the lion's share of work. Less grip results in less traction and the rear end rotates in the corner. In auto cross...you WANT the rear end to lose traction when you let off the throttle otherwise you would nose dive into every corner. The issue gets more complex when you factor in the effect of throttle on chassis movement.

Here is more info for you to digest:
AutoCross Secrets - On FWD - K20A.org .:. The K Series Source . Honda / Acura K20a k24a Engine Forum
 
21 - 40 of 69 Posts
Top