inverted tie rod end or Roll centre adjuster?

Hey guys,

have searched about this topic, but I still couldn't find a satisfying answer for this issue.

Obviously, people with either DC5 or EP3 face this problem (a horrible geometry angle on the tie rods) when they lower their cars.

now my question is: is it recommended to use inverted tie rod ends (AKOM, T1R etc.) and yes I have heard some issues with the T1R

J's racing tie rod set (I know ChargeR wouldn't recommend this, but I would like the opinion from some people since its not an inverted unit) OR

just simply bolting the Roll centre Adjuster from J's racing and use OEM tie rod and tie rod ends?

Thanks guys
much appreciated :wave:

Quote:

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Originally Posted by blk_shadow

Hey guys,

have searched about this topic, but I still couldn't find a satisfying answer for this issue.

Obviously, people with either DC5 or EP3 face this problem (a horrible geometry angle on the tie rods) when they lower their cars.

now my question is: is it recommended to use inverted tie rod ends (AKOM, T1R etc.) and yes I have heard some issues with the T1R

J's racing tie rod set (I know ChargeR wouldn't recommend this, but I would like the opinion from some people since its not an inverted unit) OR

just simply bolting the Roll centre Adjuster from J's racing and use OEM tie rod and tie rod ends?

Thanks guys
much appreciated :wave:

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Roll centers are great and should be had if you track your car regularly.

To me, the point of inverted tie rod end is to, a) Correct/improve tie rod angle and b) Increase the ability adjust more toe when you run more camber as oem runs out of adjustment.

Alternatively, you can run an AKOM (style) steering block which raises the tie rods at the steer rack!

The parts you mention have a number of different functions which of them are you trying to achieve?

Inverted tie rod ends: Will make the angle of the tie rods more horizontal and in the process completely change the bump steer (toe change with suspension droop and compression) characteristics of the front end. May also have a positive effect on steering rack longevity because it reduces the (very small) up and down loads on the rack. I can't comment on this because I have always had inverted ends since my car has been lower, and I have also changed tie rods 3 times and given my steering rack a lot of abuse and it still thrives on life.

Aftermarket tie rods: Generally used to obtain more toe adjustment on a lowered DC5 or EP3 with either a lot or not much camber. I have used J's Racing tie rods and whilst they looked nice they failed after one track event and less than 5000km. I have read of a number of other failures too. I changed to a set of modified stock tie rod ends and I haven't had a problem since although I can't recommend you do that either because shortening the rods makes them dangerously thin, see this thread for more information: LINK

Roll centre adjusters: Designed to raise the roll centre in a lowered car to reduce the roll moment and hence reduce roll. In theory these are a great idea but one has to consider that they will have a completely unknown effect on:

a) The front roll centre height and the way the roll centre migrates with suspension movement.

b) The front camber curve, or the amount of camber gained or lost as the suspension compresses.

c) The front bump steer behaviour.

d) Jacking forces.

e) Other stuff that I don't know that JohnL probably does :p.

So I personally am reluctant to make such a major change without any sort of information. If however J's Racing, for example, provided reliable data on suspension geometry at a given lowered ride height and hence info on what effect the RCAs would have on the aspects I mention above then I would be much more inclined to recommend installing them.

So which of these effects are you trying to achieve?

Thanks for the reply guys, very informative.

ChargeR: what I'm trying to achieve is, to straighten up or at least close to flatten up the tie rods to reduce the stress on the steering rack. plus to give a little more of a negative camber at the front. my car is not that low, 2 finger gaps between the tyres and the wheel arches.

I'm going to track the car in a very near future, and I don't want to go down with this OEM-angled set up on the tie rods, as I believe they r not recommended for track abuse for the amount of stress given to the steering rack.

also, are the J's tie rods length-adjustable? or are they in fixed length?

because I read about some inverted tie rods you can't use cotter pin to secure them, hence you have to use nuts, and also the danger of the tie rod ends falling off.

Js racing or Buddyclub RCA will help edwin

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Originally Posted by kongfu

Js racing or Buddyclub RCA will help Adwin

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which one r u using on ur DC5, Dan?

Quote:

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Originally Posted by blk_shadow

which one r u using on ur DC5, Dan?

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Js racing Roll center adjuster.

Quote:

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Originally Posted by blk_shadow

Thanks for the reply guys, very informative.

ChargeR: what I'm trying to achieve is, to straighten up or at least close to flatten up the tie rods to reduce the stress on the steering rack. plus to give a little more of a negative camber at the front. my car is not that low, 2 finger gaps between the tyres and the wheel arches.

I'm going to track the car in a very near future, and I don't want to go down with this OEM-angled set up on the tie rods, as I believe they r not recommended for track abuse for the amount of stress given to the steering rack.

also, are the J's tie rods length-adjustable? or are they in fixed length?

because I read about some inverted tie rods you can't use cotter pin to secure them, hence you have to use nuts, and also the danger of the tie rod ends falling off.

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The J's tie rods are the same in general design as the OEM rods they simply allow more toe adjustment in both directions. ie. you will be able to get more toe in and more toe out compared to using the OEM tie rods. This allows you to get your toe to zero or toe'd out with significant negative camber. I had -5 front camber and zero toe when I used mine. Here is what the junky J's tie rods look like (on the left):

http://img395.imageshack.us/img395/5...5forwebjj1.jpg

They will not, however, change the angle of the tie rods if that is what you are concerned about. If you must achieve that then I would recommend the steering bracket made by 0857 from ClubRSX although I am not sure if it works in EP3Rs. It will allow you to retain a normal OEM style enclosed ball joint at the tie rod end which are very reliable and quiet compared to the open Heim joints used in the T1R and other inverted tie rod end kits which can become noisy and won't ever be as reliable as an OEM part.

Just be aware that changing the angle of the tie rods has some pretty significant effects on bump steer and these effects may not be good.

Quote:

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Originally Posted by kongfu

Js racing or Buddyclub RCA will help edwin

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Apologies in advance because you may know something that I do not, but did you read the above post that I have quoted. Roll Centre Adjusters will have a very minimal effect on both the angle of the tie rods and on the amount of toe adjustment available.

Quote:

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Originally Posted by chargeR

The J's tie rods are the same in general design as the OEM rods they simply allow more toe adjustment in both directions. ie. you will be able to get more toe in and more toe out compared to using the OEM tie rods. This allows you to get your toe to zero or toe'd out with significant negative camber. I had -5 front camber and zero toe when I used mine. Here is what the junky J's tie rods look like (on the left):



They will not, however, change the angle of the tie rods if that is what you are concerned about. If you must achieve that then I would recommend the steering bracket made by 0857 from ClubRSX although I am not sure if it works in EP3Rs. It will allow you to retain a normal OEM style enclosed ball joint at the tie rod end which are very reliable and quiet compared to the open Heim joints used in the T1R and other inverted tie rod end kits which can become noisy and won't ever be as reliable as an OEM part.

Just be aware that changing the angle of the tie rods has some pretty significant effects on bump steer and these effects may not be good.



Apologies in advance because you may know something that I do not, but did you read the above post that I have quoted. Roll Centre Adjusters will have a very minimal effect on both the angle of the tie rods and on the amount of toe adjustment available.

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hmm...yeah...thats the catch between Ep3R and Dc5R, not everything can be shared.

looks like there's only one way to go.

Thanks for the help guys! :thumbsup:

I'm running the Mugen Sport Suspension on my car and I believe it drops the ride height by 1.4 inches all around. For a drop like that, would running an inverted tie rod be overkill or would I be able to benefit somehow?

More reading in this area is needed, perhaps after exams though.

I recently put the J's RCAs in and I'm happy with them. At first I thought, "yeah its made a difference, front rolls less than before, feels good" but after driving a little longer I noticed a couple things.

Firstly, it significantly reduced bumpsteer. Previously, just to travel in a straight line I was having to make many corrections to the steering as I traveled over rough roads since the front was affected by bumps and any changes in camber quite significantly.

The other change, which is probably due to an alignment issue in the first place, was that if I hold the steering wheel in place and give any amount of throttle, the car would veer to the left very noticeably. With the RCA's, its absolutely gone.

A good upgrade for me but labour cost almost as much as the part itself. (I wouldn't want to attempt doing this myself after having a look at what it entailed).

On another note, thank you ChargeR for the DIY on the ESMM's, though for the EP3 its a bit different under there (mainly the front engine mount) and that required the front bar and radiator supports (and one fan) to come off before the engine mount would pop out!

On the DC5 race cars we run Mugen steering arms on the struts, without them any more than 25 mm of lowering results in massive bump steer. The standard steering arms and tie rod ends are fine for the amount of toe out, a maximium of 3 mm each side and negative camber we run, a maximum of 4 degrees.

Cheers
Gary

Quote:

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Originally Posted by Sydneykid

On the DC5 race cars we run Mugen steering arms on the struts, without them any more than 25 mm of lowering results in massive bump steer. The standard steering arms and tie rod ends are fine for the amount of toe out, a maximium of 3 mm each side and negative camber we run, a maximum of 4 degrees.

Cheers
Gary

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So given that the Mugen SS lowers my car by 1.4 inches (35mm), a modification of some sort is needed for my tie rods?

The bump steer on our cars is also a function of the very small caster angles too, isn't it?

Quote:

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Originally Posted by Jibz

So given that the Mugen SS lowers my car by 1.4 inches (35mm), a modification of some sort is needed for my tie rods?

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Nope, not the tie rods, the steering arms. You need a set with the tie rod end taper downwards, instead of upwards like the standard steering arms.

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The bump steer on our cars is also a function of the very small caster angles too, isn't it?

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Nope, caster realy has nothing to do with bump steer. Bump steer is changes in the toe settings as the suspension moves up and down. For example you set the car at zero toe at normal ride height and it toes out 5 mm when the suspension compresses 50 mm. Then it toes in 5 mm when the suspension extends 25 mm. So it drives down the road toeing in and out every time it hits a bump, making the car steer all over the place. Hence the term "bump steer".

It's even worse for a race car where the constantly changing toe angle disrupts the tyre's contact patch and it loses traction. So the car won't hold a line through a corner, it steers and slides all over the place. Very slow and, maybe more importantly, very unsettling for the driver.


Cheers
Gary

Good info Gary. I have a couple of questions for you that hopefully aren't too off the topic of the thread.

I am also using the Mugen lower brackets and I was forced to shorten my tie rods in order to get zero toe or any toe out, how much more adjustment do you have on your tie rods? I am surprised you got away without having to modify the tie rods.

Have you measured the bump steer with the Mugen brackets in place? I am just curious. I run my car moderately low (330mm vertically from centre of the wheel to my hammered out guards) and the bump steer characteristics of the inverted tie rods when using the Mugen brackets has always interested me, although not enough to do it myself :p.

Thanks.

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Originally Posted by chargeR

Good info Gary. I have a couple of questions for you that hopefully aren't too off the topic of the thread.

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I don't think they are of topic at all. In suspension pretty much everything affects everything else, so there's not a lot of off topic anyway.

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I am also using the Mugen lower brackets and I was forced to shorten my tie rods in order to get zero toe or any toe out, how much more adjustment do you have on your tie rods? I am surprised you got away without having to modify the tie rods.

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By "shorten the tie rods" do you mean cut ands re thread them or simply adjust their length by the thread provided?

When you lower a DC5 without changing the steering arms you have to wind out the tie rods to get the static toe back where it belongs. On the other hand, when you lower a DC5 and change the steering arms at the same time you don't have have to wind out the tie rods to get the static toe back where it belongs, it's pretty much right where it is.

Maybe what you are describing is simply puting the steering arms' length back close to where they were before you lowered it.

Quote:

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Have you measured the bump steer with the Mugen brackets in place? I am just curious. I run my car moderately low (330mm vertically from centre of the wheel to my hammered out guards) and the bump steer characteristics of the inverted tie rods when using the Mugen brackets has always interested me, although not enough to do it myself

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Of course, you can't have bump steer in a race car, so the target is always zero. In a production based car we very rarely achieve zero through the whole range of travel suspension, so the compromise is zero within the most commonly used travel. That 50 mm of bump and 25 mm of rebound I talked about in the previous post.

We shouldn't ignore the rear bump steer, it's just as important for handling, you just don't feel it as much through the steering.


Cheers
Gary

Quote:

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Originally Posted by Sydneykid

By "shorten the tie rods" do you mean cut ands re thread them or simply adjust their length by the thread provided?

When you lower a DC5 without changing the steering arms you have to wind out the tie rods to get the static toe back where it belongs. On the other hand, when you lower a DC5 and change the steering arms at the same time you don't have have to wind out the tie rods to get the static toe back where it belongs, it's pretty much right where it is.

Maybe what you are describing is simply puting the steering arms' length back close to where they were before you lowered it.



Of course, you can't have bump steer in a race car, so the target is always zero. In a production based car we very rarely achieve zero through the whole range of travel suspension, so the compromise is zero within the most commonly used travel. That 50 mm of bump and 25 mm of rebound I talked about in the previous post.

We shouldn't ignore the rear bump steer, it's just as important for handling, you just don't feel it as much through the steering.


Cheers
Gary

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Yep I had to cut and re-thread my tie rods as the tie rod ends were bottomed out on the tie rod and I still had toe in :). The other person I know that has used the Mugen brackets also had to do the same. What dampers are you using if you don't mind sharing?

So you are saying that those numbers posted above are the bump steer numbers that you have measured or they were around that?

[QUOTE]

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Originally Posted by chargeR

Yep I had to cut and re-thread my tie rods as the tie rod ends were bottomed out on the tie rod and I still had toe in :). The other person I know that has used the Mugen brackets also had to do the same.

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When we flipped the tie rods ends over at the lower ride height the steering arms ended up back in the same position as they were before we lowered it. So I'm not sure why you would have to shorten the steering arms.

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What dampers are you using if you don't mind sharing?

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Tein N1's in one of the cars, that I have changed the springs rates and changed the valving 5 times. The off shelf rates (spring and damper) were rediculous and the adjustments far too fine, they did basically nothing. The other car has MCA's (nee Proflex), they were spot on out of the box and I all I have done is fine tuning of the bump and rebound adjustments for each track. The car with the MCA's is faster and gentler on its tires, despite my best efforts with the Teins.

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So you are saying that those numbers posted above are the bump steer numbers that you have measured or they were around that?

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Around that, the two cars were slightly different.

Cheers
Gary

Bringing this post back alive as I need some assistance.

I just got J's RCA installed onto my EP3R and so far it feels okay but there is still whacky steering going on (steering wheel leaning to the left, and sometimes pulling heavily on some parts of the road) but that's maybe because I haven't got a wheel alignment after the installation.

If the wheel alignment doesnt fully correct my steering/bumpsteer, what would be my next step?

Get the alignment first...

Alignment should fix your issues...................

So I got my J's Racing RCA installed + wheel alignment.

Running -
F -1.25 camber, zero toe
R -2.8, -2.3 camber, +1.0 toe

Yet I still get this heavy pull on my steering on slanted roads and everytime I hit vtec on gear 2 the steering goes crazy left-right.
I've been trying to diagnose this problem for quite some time.
Though the J's Racing RCA does make a difference on bump steer which is good but doesn't fix this steering problem.

Do I need inverted tie rod ends? OR even Tegiwa Steering Rack Raisers?

Hey Post a pic of your wheel alignment read/print out.

I think you may need to go to a better shop.

I have been thru the bump steer/ Wheel pulling to one side issue on my dc5, after all the researching/spending ..... You just need to go to a shop that know their shit is all.

Quote:

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Originally Posted by amant02

Hey Post a pic of your wheel alignment read/print out.

I think you may need to go to a better shop.

I have been thru the bump steer/ Wheel pulling to one side issue on my dc5, after all the researching/spending ..... You just need to go to a shop that know their shit is all.

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Here is the print out of my current specs.

http://imgur.com/Lzm3Sx7

BUMP - Need some professional assistance.

This is an Internet forum, you're not going to get professional assistance.

The DC5/EP3 front suspension is unstable for a number of reasons, it has a lot of bump steer, high SAI, not a lot of caster and usually scrub radius issues with aftermarket wheels fitted. Your alignment sheet shows that your SAI is 1.6° different left to right which to me is enough to indicate there may be some damage to the suspension, and this difference in SAI will result in a difference in scrub radius from left to right and may be contributing to the pulling and steering kickback you're experiencing. I'd look carefully for any damage to the suspension.

What size and offset are your front wheels?

To improve the behaviour you're describing you have to increase the stability of the front steering system. There's a number of obvious ways to improve this:

- Add positive caster
- Less negative camber
- Reduced SAI
- Reduced scrub radius
- Improve the bump steer behaviour further. The J's RCA have probably improved this slightly, but measurement and then tie rod attachment point modifications are the only way to do it precisely. Due to the rack location the DC5/EP3 will always have bad bump steer behaviour over a large range of suspension movement.

Quote:

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Originally Posted by chargeR

This is an Internet forum, you're not going to get professional assistance.

The DC5/EP3 front suspension is unstable for a number of reasons, it has a lot of bump steer, high SAI, not a lot of caster and usually scrub radius issues with aftermarket wheels fitted. Your alignment sheet shows that your SAI is 1.6° different left to right which to me is enough to indicate there may be some damage to the suspension, and this difference in SAI will result in a difference in scrub radius from left to right and may be contributing to the pulling and steering kickback you're experiencing. I'd look carefully for any damage to the suspension.

What size and offset are your front wheels?

To improve the behaviour you're describing you have to increase the stability of the front steering system. There's a number of obvious ways to improve this:

- Add positive caster
- Less negative camber
- Reduced SAI
- Reduced scrub radius
- Improve the bump steer behaviour further. The J's RCA have probably improved this slightly, but measurement and then tie rod attachment point modifications are the only way to do it precisely. Due to the rack location the DC5/EP3 will always have bad bump steer behaviour over a large range of suspension movement.

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I appreciate your suggestions/feedbacks as I really want to get rid of this heavy pulling on the steering.

In saying that, I will do the followings you mentioned to improve it.
But in order to add more positive caster, reducing SAI/scrub radius, what would be the first step?

I can adjust the camber at the front as Im running BC BR coilovers but not the rears (no rear camber arms) meaning I would have to raise the car but I like how it is sitting at the moment.

At the front, Im running 17x9 +35 (225/45).


ALSO
I've read and got told, with Tegiwa Steering rack raisers, it will correct the angle of the tie rods bringing it back to OEM angle which is a reason to this steering pulling issue but I'm not 100%. Don't hear many EP3R use them.

It's not fundamentally the angle of the tie rods that is the problem causing bump steer, it's the relationship of their angle to the lower control arm angle/position and the strut top location. It's the motion of the front knuckle/upright relative to the steering tie rod that produced bump steer. The only way to fix it for sure is to measure and then make a change. I doubt that the Tegiwa rack raisers will fix anything, and will likely make it worse.

Going to a wheel offset closer to stock will reduce your scrub radius and likely improve the steering behaviour, see if you can borrow a set of +45 offset wheels and see whether it makes much difference.

It is the front camber that is affecting this behaviour, but the amount you have is not excessive so I'd look for a solution elsewhere before reducing negative camber.

You could fit aftermarket strut tops at the front to increase the caster, like these: http://dvrace.com/caster/ I've used a set like these on my DC5R and noticed an increase in straight line stability under acceleration due to the added caster (with -5° camber and 17x10+18 wheels).

If I were in your position I'd start with the wheels, and then add some positive caster, and after doing those two things then get someone to fix the bumpsteer properly, not with garbage parts like those Tegiwa things.

Quote:

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Originally Posted by chargeR

It's not fundamentally the angle of the tie rods that is the problem causing bump steer, it's the relationship of their angle to the lower control arm angle/position and the strut top location. It's the motion of the front knuckle/upright relative to the steering tie rod that produced bump steer. The only way to fix it for sure is to measure and then make a change. I doubt that the Tegiwa rack raisers will fix anything, and will likely make it worse.

Going to a wheel offset closer to stock will reduce your scrub radius and likely improve the steering behaviour, see if you can borrow a set of +45 offset wheels and see whether it makes much difference.

It is the front camber that is affecting this behaviour, but the amount you have is not excessive so I'd look for a solution elsewhere before reducing negative camber.

You could fit aftermarket strut tops at the front to increase the caster, like these: http://dvrace.com/caster/ I've used a set like these on my DC5R and noticed an increase in straight line stability under acceleration due to the added caster (with -5° camber and 17x10+18 wheels).

If I were in your position I'd start with the wheels, and then add some positive caster, and after doing those two things then get someone to fix the bumpsteer properly, not with garbage parts like those Tegiwa things.

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Guess Ill start first by chucking back on my stockies and come back with an update.

OR what if I swap my wheels around?
At the moment Im running 17x8 +32 at the rears, 17x9 +35 at the fronts. Do a switch over and see how that works out.

Adding more positive caster will be good but caster plates are not so cheap so Im leaving this as a last solution.

You can buy bushings that increase the castor angle.

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Originally Posted by amant02

You can buy bushings that increase the castor angle.

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Is it the bushings for the front LCA?

I read a post saying Mugen / Energy Suspension provide good quality bushings for this kind of issue.

Hardrace and super pro makes em.

*UPDATE*

Switching 17x9 +35 to the rears was a mistake as they were scrubbing the trailing arms.

Ive put my stockies back on (17x7+45) and its making quite a difference in holding straight but still slight pulls here and there and steers to the left when accelerating/VTEC.

Guess running 9's at the fronts are not so ideal but if you're in for the looks then why not?
But not sure if I want to run the 9's as much, as it gets quite annoying for daily driving.

Next upgrade would probably be the bushings as amant02 mentioned, maybe caster plates if I want to spend bigger.

Also to try to get my crappy wheel aligning mechanic to properly fix my bump steer. I don't know where to start...

Dunno

Okay so bump steer is out of the way now. On to torque steer.

My steering pulls to the left when I flat-foot the acceleration but when I let go of accelerate, it cruises fairly straight.

What is causing this?

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Originally Posted by SHRUKA

Okay so bump steer is out of the way now. On to torque steer.

My steering pulls to the left when I flat-foot the acceleration but when I let go of accelerate, it cruises fairly straight.

What is causing this?

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your driveshafts are different lengths and therefore have different torsional resistance, i.e. one flexes more than the other cos it's longer

the fix for this is to buy a rear wheel drive car

Bump Steer + Torque Steer is just the fun part of owning a ep3/dc5.

I get hectic Torque Steer, specially with the new light flywheel.

Fix = Hold the steering tight and be prepped to counter if required.

Quote:

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Originally Posted by SHRUKA

*UPDATE*

Switching 17x9 +35 to the rears was a mistake as they were scrubbing the trailing arms.

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Those specs are fine. You just need to run a little camber with rolled guards.

Quote:

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Originally Posted by amant02

Bump Steer + Torque Steer is just the fun part of owning a ep3/dc5.

I get hectic Torque Steer, specially with the new light flywheel.

Fix = Hold the steering tight and be prepped to counter if required.

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I like dis.

Hey guys, did anyone have or had lining up problem when installing hardrace inverted tie rod ends on EP3?