Energy Suspension trailing arm bush HELP!!!
- Thread starter R13ngy
- Start date
stevenEK9
trackattack
- Joined
- Mar 11, 2007
- Messages
- 4,250
RTA bushes are the same part for all integras and civics
Just fit oem ones, there is no need to fit aftermarket ones here unless it is a pure track car........
This is taken off another forum, need I say any more?
The rear suspension on the DC2 (and a lot of other Honda's) is quite special.
The trailing arm bush is designed so the wheel can move backward or forward - that's why there's so much play in it.
The trailing arm is controlled by 3 arms. Simplifying slightly:
The lower control arm takes the main side loads.
The upper control arm controls camber.
The front control arm controls toe.
The special bit comes in when you brake. When you're braking, the tyre as it grips wants to move slower than the car currently is. That pulls the wheel backwards compared to the car.
Now, the trailing arm bush is specifically designed to allow the wheel to move back like this under braking. You're probably thinking that's useless and bonkers. Not so. Look at the lower control arm, and the front control arm. When the trailing arm moves back, it's held by both of those arms which limit where it can move. The front control arm is a lot shorter than the lower control arm. So when the trailing arm moves backward under the braking load, the front arm will angle more than the lower arm simply because it's shorter. That means the front of the trailing arm has to move inwards. Adding toe in.
To put it simpler, the trailing arm bush is designed to be soft so that the arm moves back under braking, causing the front control arm to pull the front of the trailing arm in, adding toe in, stabalising the back end under braking.
Even more clever is the way the amount of toe it added is purely related to how far back the wheel is pulled, which is related to how hard you're breaking and how much grip that wheel has. So if one wheel loses grip compared to the other, the toe of the two wheels will differ, helping stabalise the rear end. Really cool, and clever.
Honda has several patents on it.
If you put a much harder bushing in place of the standard trailing arm bush, you stop the backward movement under braking which stops the toe change under braking. Whether you want that or not, is up to you. But if you do it, you should consider what toe to run at the back as it's effectively static after the bush change. You can set the car up to work well either way - I'm just making the point that removing this cool toe change under braking behaviour without considering the overall handling effects isn't necessarily a good thing for everyone. I've certainly seen enough people who've probably been saved from a spin by the standard behaviour when they end up braking too deep into a corner to consider it worthless.
Just thought people might find that of interest... handling is a lot more subtle that you'd think
Just fit oem ones, there is no need to fit aftermarket ones here unless it is a pure track car........
This is taken off another forum, need I say any more?
The rear suspension on the DC2 (and a lot of other Honda's) is quite special.
The trailing arm bush is designed so the wheel can move backward or forward - that's why there's so much play in it.
The trailing arm is controlled by 3 arms. Simplifying slightly:
The lower control arm takes the main side loads.
The upper control arm controls camber.
The front control arm controls toe.
The special bit comes in when you brake. When you're braking, the tyre as it grips wants to move slower than the car currently is. That pulls the wheel backwards compared to the car.
Now, the trailing arm bush is specifically designed to allow the wheel to move back like this under braking. You're probably thinking that's useless and bonkers. Not so. Look at the lower control arm, and the front control arm. When the trailing arm moves back, it's held by both of those arms which limit where it can move. The front control arm is a lot shorter than the lower control arm. So when the trailing arm moves backward under the braking load, the front arm will angle more than the lower arm simply because it's shorter. That means the front of the trailing arm has to move inwards. Adding toe in.
To put it simpler, the trailing arm bush is designed to be soft so that the arm moves back under braking, causing the front control arm to pull the front of the trailing arm in, adding toe in, stabalising the back end under braking.
Even more clever is the way the amount of toe it added is purely related to how far back the wheel is pulled, which is related to how hard you're breaking and how much grip that wheel has. So if one wheel loses grip compared to the other, the toe of the two wheels will differ, helping stabalise the rear end. Really cool, and clever.
Honda has several patents on it.
If you put a much harder bushing in place of the standard trailing arm bush, you stop the backward movement under braking which stops the toe change under braking. Whether you want that or not, is up to you. But if you do it, you should consider what toe to run at the back as it's effectively static after the bush change. You can set the car up to work well either way - I'm just making the point that removing this cool toe change under braking behaviour without considering the overall handling effects isn't necessarily a good thing for everyone. I've certainly seen enough people who've probably been saved from a spin by the standard behaviour when they end up braking too deep into a corner to consider it worthless.
Just thought people might find that of interest... handling is a lot more subtle that you'd think
- Joined
- Aug 18, 2008
- Messages
- 4,081
Good stuff there Steven, I never realised that about the rear suspension on Civics!
It is almost enough for me to consider going back to OEM, however it would seem to suggest that the polybush would effectively increase toe (or reduce the gain of toe-in) under braking, which I think is a useful trait for the autotesting I do, should be working to improve turn in under braking if I am thinking correctly?
I certainly have noticed it to be slightly unstable under heavy braking on the road, although this has never really caused a problem.
+1 rep for you on that one!
It is almost enough for me to consider going back to OEM, however it would seem to suggest that the polybush would effectively increase toe (or reduce the gain of toe-in) under braking, which I think is a useful trait for the autotesting I do, should be working to improve turn in under braking if I am thinking correctly?
I certainly have noticed it to be slightly unstable under heavy braking on the road, although this has never really caused a problem.
+1 rep for you on that one!
ramboteamjon
Well-Known Member
- Joined
- Apr 21, 2008
- Messages
- 3,010
I had the ES bushing in the RTA's on my EK9 for 2 weeks, HATED IT and fitted OEM ones! Million times better!! 
- Joined
- Aug 18, 2008
- Messages
- 4,081
I had the ES bushing in the RTA's on my EK9 for 2 weeks, HATED IT and fitted OEM ones! Million times better!!
What exactly did you hate about them, and how did the OEM ones improve it?
Genuine question as I am running ES RTAs and I don't really have any gripes with them, just wondering what everyone elses are?
Smithy18
EK4 VTI-S B18C6
- Joined
- Feb 15, 2009
- Messages
- 725
Hi mate, you can have the arm for £25 all 3 bushes in very good condition, the arm came from a 98 ek9.
i'm located in wiltshire england.
let me know mate.