DC2 VTI-R Overhaul

[shebangs]

Can anyone comment, or fill in the blanks from the below proposed DC2 Overhaul?

Coilover: Tein Flex
Front Swaybar: ?
Rear Swaybar: 24mm Whiteline
Front Strut: ?
Rear Strut: ?

Anything else I could possibly look at? Do I have to reinforce the subframe after installing the heavy duty Swaybars?

What about Bushes?

Currently suspension is stock.

Thanks,
Matt

[Q_ball]

Why did you post this in the Audio section?

[GOODAN]

Definitely do some research. There are heaps of posts about this. I can give you a quick heads up though :)

I have Tein Super Street with DC2R LCAs and had major problems fitting the Whiteline rear swaybar. The bar constantly was rubbing against the LCAs (and no it wasn't installed upside down). In the end I brought my car into Fulcrum and they too couldn't work it out so I ended up getting my money back.

So now I've got DC2R rear swaybar but waiting to get a subframe reinforcement kit otherwise u will suffer subframe tear out. Possible options to choose for this are the Beaks kit or the ASR brace. Check the Ozhonda traders.

There is no real need to upgrade the front sway bar as it is good enough stock. Good luck...

[bennjamin]

IMO




Front Swaybar: LEAVE STOCK

Front Strut: NO NEED
Rear Strut: NO NEED

Anything else I could possibly look at? Do I have to reinforce the subframe after installing the heavy duty Swaybars?


The whiteline kit you speak of , includes reinforcement to suit.
Currently tho , whiteline is redesigning their kits for better reinforcement so hang in there.
IMO , the biggest handling difference you will get is from upgrading the rear swaybar. Next , would be a FRONT CASTOR KIT. This is a great hidden mod that increases turn in / reduces understeer and increases overall feel of the car.
Dont forget , once its all installed to get a decent alignment ! And decent tyres too :)

[T-onedc2]

I have ITR suspension, with ITR lca's and JDM 23mm rear sway bar + Beaks subframe reinforcement kit.
As Bennjamin said a front castor kit is a great idea, yet to get one myself tho.
Feel free to pm me any q's.

[shebangs]

I have Tein Super Street with DC2R LCAs and had major problems fitting the Whiteline rear swaybar. The bar constantly was rubbing against the LCAs (and no it wasn't installed upside down). In the end I brought my car into Fulcrum and they too couldn't work it out so I ended up getting my money back.

Do Flex have the same problem?


The whiteline kit you speak of , includes reinforcement to suit.
Currently tho , whiteline is redesigning their kits for better reinforcement so hang in there.
IMO , the biggest handling difference you will get is from upgrading the rear swaybar. Next , would be a FRONT CASTOR KIT. This is a great hidden mod that increases turn in / reduces understeer and increases overall feel of the car.
Dont forget , once its all installed to get a decent alignment ! And decent tyres too :)

What's the ETA on this? By reinforcement, I remember reading numerous threads on peoples subframes from tearing from using the Whiteline heavy Duty swaybar kit?
Coilovers + LCA
Rear Swaybar
and the Front Castor?

That's fine by me, saves me money. I could always blow some cash later down the track on Cusco Front/Rear Struts etc if I wanted, but yeah thanks, as you said definately not bang for buck.

I'm still a little curious if Flex will be too hard, even at the softest settings for when the GF is in the car or Driving to work.

[shebangs]

I have ITR suspension, with ITR lca's and JDM 23mm rear sway bar + Beaks subframe reinforcement kit.
As Bennjamin said a front castor kit is a great idea, yet to get one myself tho.
Feel free to pm me any q's.

So you just upgraded to ITR Springs/Shocks? May I ask why didn't you go one above and get decent Coilovers + LCA? It wouldn't be that much more would it?

[ACTI0NMAN-1]

IMO



The whiteline kit you speak of , includes reinforcement to suit.
Currently tho , whiteline is redesigning their kits for better reinforcement so hang in there.
IMO , the biggest handling difference you will get is from upgrading the rear swaybar. Next , would be a FRONT CASTOR KIT. This is a great hidden mod that increases turn in / reduces understeer and increases overall feel of the car.
Dont forget , once its all installed to get a decent alignment ! And decent tyres too :)

speaking of whiteline, is there a trader on here that still does them because i searched and couldnt find the thread. maybe i'm not using the corredct key words,

[bennjamin]

pm ëuro69 - he deals with them

[ginganggooly]

I had the castor kit (effectively some longer bolts and a few washers to push the LCA forward) on from some time. It caused a good amount of rubbing, creaks and groans from the front end, and required constant monitoring of the LCA bolts.

Yes it does feel good, but not worth the hassle IMO.
I've since removed it.

[xtercii]

do all caster kits do that or just the whiteline?

[bennjamin]

do all caster kits do that or just the whiteline?

not all - some replace the lower bush and bring it forward.
The whiteline kit , while works is alittle dodgy and does rub in places.
Best to swap the upper control arms side to side , which will give you more castor too.

[T-onedc2]

So you just upgraded to ITR Springs/Shocks? May I ask why didn't you go one above and get decent Coilovers + LCA? It wouldn't be that much more would it?
They are actually very good for a stock setup, and I paid about $350 for the lot with about 23,000k's on it. Decent coilovers are much more.

edit: and as the ride is stiff but not bone-jarring no one complains about the ride comfort.

[tinkerbell]

to increase castor in DC2:

just swap the LHS and RHS upper control arms!

it is free and more reliable than the whiteline crap assed washer method...

[T-onedc2]

to increase castor in DC2:

just swap the LHS and RHS upper control arms!

it is free and more reliable than the whiteline crap assed washer method...
Hey just did that on the weekend and I'm happy with the results!

[string]

Well if screwing with your bump steer is a side effect you're happy with then good work :p

[T-onedc2]

Well if screwing with your bump steer is a side effect you're happy with then good work :p
please explain?

[string]

Bump steer is the term given to toe (steering angle) as a function of suspension compression. As you compress or droop the suspension, your toe will change as in all suspension design there are trade-offs limiting perfect control arm placement (space and steering rack location in most of our cars). Most people want to have zero bump steer, which means that steering angle doesn't change as suspension travels.

Standard bump steer is pretty good, not much change from zero, and when it does it tends towards a linear or exponential curve - predictable.

Someone on honda-tech used a bump-steer gauge to test the effects on bump-steer with the control arm swap and the final curve ended up looking like a parabola i.e. it started positive (or negative can't remember) at one end of the the suspension travel, went to back to zero then back out to the same direction again. Many people found this lead to instability when entering high speed braking as the front suspension compressed under the braking load.

If you search honda-tech you'll find the thread.

Also, you may have problems with axels if you add too much castor, but i've seen no evidence so take that as you wish.

[T-onedc2]

I looked closely at how the castor change would affect the other components and by adjusting the top arms the axels aren't affected in any way, but I can see they would be with a castor kit fitted to the lower arm as it would push the slightly forward.

In regards to increased -ve toe (toe out), it helps keep the front on the desired cornering line as the inside wheel will keep pulling into the turn.

[tinkerbell]

Well if screwing with your bump steer is a side effect you're happy with then good work :p

yep, it screwed mine up so bad i didnt even notice it :wave:

more castor > mild 'bump steer' effect anyways - even if was noticable (which it is not)

and FWIW - i was taking turn one at wakie at around 170 and braking hard,

same with braking at 180 into turn two at eastern creek? no instability.

maybe it is due to the 12k fr spring rates?

[ekhybrid]

does swapping uca 2 increase castor apply to eks as well?

[tinkerbell]

does swapping uca 2 increase castor apply to eks as well?

does the EK ahve UCA's like this:

http://home.exetel.com.au/tinkerbell/DC2frontsussy.jpg

[bennjamin]

does the EK ahve UCA's like this:

http://home.exetel.com.au/tinkerbell/DC2frontsussy.jpg

to be exact , NO. The EK UCA is mounted on the sides , rather than the TOP like EG/DC/s. (as long as the swap is possible/lines up) Exact same principle Dave. Should work the same.

[tinkerbell]

for those who have PM'd me about the benefits of this UCA swap and any noticable bad effects, please read this FAQ on castor:

http://www.whiteline.com.au/default.asp?page=/faqsusp01.htm

i have had no noticable negative effects, but noticably better cornering ability and directional stability on the race track.

(i must state that i also replaced the OEM bushes with Energy Suspension poly bushes at the same time.)

[string]

more castor > mild 'bump steer' effect anyways - even if was noticable (which it is not)

Not always true. There's always going to be a suspension setup in which all variables can be independantly varied.

Hey i'm just telling you the truth which has come about from actual tests. Your bump steer is now not as good as it was before, you can't argue with that. You also can't argue that it has negative effects, noticable to you or not. Maybe the guys on honda-tech race a bit more hardcore than you do :D

[tinkerbell]

whatever dude! :wave:

[bennjamin]

i agree with the above. Whatever ! I too have this DIY castor kit ( going from the whiteline kit) and i cannot feel anymore or less "bumpsteer" than normal. (yes i do know what it is)
Its a great mod :)

[czy_sol87]

after the UCA swap over do u guys get a wheel allignment done?

[bennjamin]

can if you want.

[czy_sol87]

awsome thanks for the info, didnt know u could increase caster that way
+rep points

[tinkerbell]

after the UCA swap over do u guys get a wheel allignment done?

i didnt, but depends how it feels afterwards...

mine felt exactly the same afterwards, so i didn't think it needed any changing...

[czy_sol87]

i didnt, but depends how it feels afterwards...

mine felt exactly the same afterwards, so i didn't think it needed any changing...

yeh when i put in my coilovers the car felt the same, but when i got it alligned the toe, camber, etc was totally out of wack

[T-onedc2]

Mine felt the same too so I don't plan to at this point.

[tinkerbell]

i probably dont have to point out the obvious, but an UCA swap is hardly as drastic as a swap to coil-overs...

[Muzz]

Can anyone comment, or fill in the blanks from the below proposed DC2 Overhaul?

Coilover: Tein Flex
Front Swaybar: ?
Rear Swaybar: 24mm Whiteline
Front Strut: ?
Rear Strut: ?

Anything else I could possibly look at? Do I have to reinforce the subframe after installing the heavy duty Swaybars?

What about Bushes?

Currently suspension is stock.


Thanks,
Matt

For the front strut brace, you cant beat a 3point design that also mounts to the firewall.
Check out my signature, near new edelbrock strutbrace for the dc2, at $200 its a steal ($295 new):thumbsup: :cool:

[tinkerbell]

you cant beat a 3point design that also mounts to the firewall.

(except in a front end collision!)

[Muzz]

Ive read plenty of very good suspention books and have never come across a relationship between bump steer and castor.

As im sure you guys know, bump steer is caused by the angles of the steerings tie rod ends, moreso there angle in the vertical plane. As the suspension is compressed the angle increases pulling the steering knuckle inwards toward the car.

I fail to see why swapping ucas to move the mounting point backwards for a small increase in castor (probaly only 1-2 degrees), is going to alter the angle of the steering arms in anyway that will be detrimental to bump steer.

Adding this slight caster would move the steering knuckle joint downwards, which is exactly whats required when the bump steer angles are bad due to lowering (the steering arms are angled upward due to lowering, tilting the hub back will make the arms more horizontal).

Im really interested in those graphs you mentioned string but cant seem to find em. Im really keen to check it out though if you can see them.

Was it a single trace of the bumpsteer after swapping the uca's, because that woulnd prove anything usefull, it needs to compare the traces of the bumpsteer both before and after the ucas are swapped.

[tinkerbell]

Ive read plenty of very good suspention books and have never come across a relationship between bump steer and castor.

As im sure you guys know, bump steer is caused by the angles of the steerings tie rod ends, moreso there angle in the vertical plane. As the suspension is compressed the angle increases pulling the steering knuckle inwards toward the car.

I fail to see why swapping ucas to move the mounting point backwards for a small increase in castor (probaly only 1-2 degrees), is going to alter the angle of the steering arms in anyway that will be detrimental to bump steer.

Adding this slight caster would move the steering knuckle joint downwards, which is exactly whats required when the bump steer angles are bad due to lowering (the steering arms are angled upward due to lowering, tilting the hub back will make the arms more horizontal).

Im really interested in those graphs you mentioned string but cant seem to find em. Im really keen to check it out though if you can see them.

Was it a single trace of the bumpsteer after swapping the uca's, because that woulnd prove anything usefull, it needs to compare the traces of the bumpsteer both before and after the ucas are swapped.

yes, the funny thing is that the method of reducing "bumpsteer" effect that is experienced on extremely lowered vehicles (as mentioned on the HT threads) is to lower the mount point of the steering control arm in relation to the hub (e.g. by mounting it onto the underside...) to ensure the steering arm retains a similar angle to the original angle prior to lowering...

using your imagination (or do it practically if you like), what is the effect of the LCA swap on the vertical position of the steering control arm?

what does this tell you about *possible* bumpsteer effects?

[tune2look]

I fail to see why swapping ucas to move the mounting point backwards for a small increase in castor (probaly only 1-2 degrees), is going to alter the angle of the steering arms in anyway that will be detrimental to bump steer.


I believe whiteline kit will give you up to 2.5.
So 1~2 degrees will do stuff.
People even worry about few psi on tyre pressure.
In suspension wise, 1mm, 1 degree will do a lot I think.

*I remember Ben's castor kit is only around 1.5?

[tinkerbell]

Muzz is not saying that the UCA swap doesnt increase castor.

[midnightdood]

To all that have done this mod. Are the front wheels pushed back measurably?

[T-onedc2]

To all that have done this mod. Are the front wheels pushed back measurably?

It tilts back slightly but you wouldn't ever pick it.