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-   -   This is the roll center, suspension pickup, and steering angle modification thread. (#/f/showthread.php?t=296725)

SoSideways 08-24-2010 08:32 AM

I'm just saying.

Everytime roll center correction was brought up, especially for the S-chassis, I always see that picture quoted and someone goes "how about doing it up like this? seems easy?" and then an engineer, or just somebody that knows what they're doing will chime in and be like "don't do it like that, it places the rod end in bending."

hahaha

But in any case, yes, that car was tracked regularly, but I don't think they would have made any mention of changing out the rod end in an article, unless they have like a blog type report of everytime they go out racing or something.

SoSideways 08-24-2010 09:00 AM

I forgot to mention this whole morning.

Last night I was working on the car, and I noticed that I pretty much ran out of tie rod and rod end adjustment on my tie rod assembly on the passenger side front and still was not able to bring the toe out into an acceptable range, so then I remembered someone mentioning that the racks are actually longer on one side in this thread.

I'm pretty sure whoever said that is correct, because I then did a little testing.

I unhooked the steering column coupler from the rack and moved the rack over a little bit to try and "center" it a little more, but then I got a lot more steering wheel turn to one side than the other. I got like 1.75 turns to the left I think, and then only like 1 turn to the right.

So then I was like "well, this isn't right", so I unhooked the steering coupler from the rack again, and I moved it back, but moved it over a few teeth. Now I got a lot more angle on the passenger side than the driver's side front, but the steering wheel was about even in either directions as far as center to lock goes.

Then it hits me, for some reason, the passenger side tie rod isn't even hitting the steering stop, which is set all the way in just like the driver's side front, and the wheel is hitting the tie rod end, which is what's stopping the party.

So then I moved the steering coupler over a couple of teeth back the other way, and adjusted the steering stopper on the passenger's side FLCA, and now I get about the same angle on both sides, and I get 1.5 turns in either direction from center to lock.

Weird thing too that I noticed last night was that, my passenger's side FLCA is set to about the same length as the driver's side FLCA, but the bolt is slightly pointed towards the brake rotor, and I had a lot more brake rotor clearance between the rotor and the FLCA.

So I think the rack is indeed longer on one side than the other, and I think my chassis is tweaked up front.

Oh well, I barely have enough tie rods to make it work right now, and at this point, as long as it works, I'm happy.

Just gotta anti-seize and put the passenger side coilover back together, then torque all the nuts/bolts to spec, and the passenger side is done.

Gotta dremel more of the driver's side FLCA, and then tighten the 2 bolts on the steering coupler, and I can move on to the rears.

derek king 08-24-2010 10:30 AM

you were deffinately onto something BUT You dont have to go through all of that to center your rack

SoSideways 08-24-2010 12:07 PM

How else do you propose to do it?

And I'm pretty anal about this stuff, so if I deem a certain way the "best" way to do it, I'm gonna do it.

In either case, there's definitely more angle to be found in my setup, but to be honest, I don't think I'll ever need it, and getting there means spending more time and money on the car, and at this point, I don't want to go there, so that's another reason why I didn't "truly center the rack".

DC Dan MAX USA 08-24-2010 06:10 PM

I took these pictures after we installed the new inner tie rods & did alignment and before we tested the car.

I thought it looked cool up on the rack with all the new parts.

And then I drove it for a little bit and...

WOW

endless angle and the predictable suspension feels like an extension of the driver.

hard to describe but that about sums up how it feels with the new settings and parts

http://www.gtfactory.jp/cms/e107_fil...2_p1070325.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070326.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070327.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070329.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070330.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070331.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070324.jpg

SoSideways 08-24-2010 06:31 PM

OMG ROOK AT THAT SUSPENSION PR0N!!!!!!!!!!!!!!! :fap fap fap fap fap:

D.Adams 08-24-2010 06:31 PM

Quote:

Originally Posted by DC Dan MAX USA (Post 3605433)
I took these pictures after we installed the new inner tie rods & did alignment and before we tested the car.

I thought it looked cool up on the rack with all the new parts.

And then I drove it for a little bit and...

WOW

endless angle and the predictable suspension feels like an extension of the driver.

hard to describe but that about sums up how it feels with the new settings and parts

http://www.gtfactory.jp/cms/e107_fil...2_p1070325.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070326.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070327.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070329.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070330.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070331.jpg
http://www.gtfactory.jp/cms/e107_fil...2_p1070324.jpg


Dan where can i get those arms.

SoSideways 08-24-2010 06:33 PM

From Dan at Powered By Max. I herd he hookz you upz.

Def 08-24-2010 07:59 PM

Quote:

Originally Posted by SoSideways (Post 3605465)
From Dan at Powered By Max. I herd he hookz you upz.

Totally brah... totally. :stupid:

GripTerror 08-24-2010 09:23 PM

damn that's baaaad aaaaaaaaaaaaayyyyyyyyzzzzzzzzzzzzzzzzzzzzzzzzzzz, deeaaaaaaaaaazzzzzzzzzz lol

swiftmini 08-24-2010 11:53 PM

Quote:

Originally Posted by PoorMans180SX (Post 3604588)
Negative, I had SPL outers with both correction spacers.





This is a hard one man, it depends on your springs rates, total roll resistance, and ride height.

I just grabbed some good info from Mike Kojima's "Making It Stick" that was in Sport Compact Car.



On another note, apparently I can edit my original post again, I'll try and get to that this week!

Thats very helpful! Thankyou :D although i need to go away and do some reading because iam confused by the centre of gravity points. i thought there was one centre of gravity point! not one at either end :p

For example i just googled centre of gravity and found this vvvvv and that follows my understanding of working out cofg

Longacre Racing Online -- Tech Article "Center of Gravity Height"

I hope to get onto some scales soon so i can work out where iam right now.

One thing i have noticed is my car appears quite fast/snappy during transition from a drift one direction to the other. I guessed this was probably down to having stock rear lca back on the car instead of the godspeed, that and the 40mm corrected front hubs, have probably messed up the roll axis for me.

Kev

swiftmini 08-24-2010 11:54 PM

Dan, thats a setup to bed proud of psm for winners :D

now hurry and release some stuff so i can b uy it :D

swiftmini 08-24-2010 11:56 PM

Dan, thats a setup to bed proud of psm for winners :D

now hurry and release some stuff so i can b uy it :D

Slidin' Sam 08-25-2010 01:03 AM

SoSideways - Yes, the steering rack is off-centered. I believe you should have more steering angle when turning in the direction of the passenger...so to the right for you and to the left for me. I am not positive, but I believe the steering rack is off-set like that because of where the input for steering (ie steering colum) is located in relation to the rack. The d-max steering rack spacers are supposed to correct this (as well as give you an extra 7-8 degrees) and give you equal steering left and right.

nieko 08-25-2010 01:40 AM

That is incorrect about the DMAX spacers.

they are not side specific, all they do is add angle.

thefro526 08-25-2010 06:03 AM

Quote:

Originally Posted by DC Dan MAX USA (Post 3605433)

Dan, Have you had a chance to take any measurements of the angle you were able to achieve with that setup? It looks like you're well in excess of 55* on the leading wheel.

The suspension setup is impressive without a doubt. I can't wait until these parts are available for purchase.

95KA-Turbo 08-25-2010 06:45 AM

Quote:

Originally Posted by swiftmini (Post 3605983)
Thats very helpful! Thankyou :D although i need to go away and do some reading because iam confused by the centre of gravity points. i thought there was one centre of gravity point! not one at either end :p

For example i just googled centre of gravity and found this vvvvv and that follows my understanding of working out cofg

Longacre Racing Online -- Tech Article "Center of Gravity Height"

I hope to get onto some scales soon so i can work out where iam right now.

One thing i have noticed is my car appears quite fast/snappy during transition from a drift one direction to the other. I guessed this was probably down to having stock rear lca back on the car instead of the godspeed, that and the 40mm corrected front hubs, have probably messed up the roll axis for me.

Kev

This probably isn't as accurate as doing it another way, but this is a super simple COG calculator for the front of the car:

cgh.xls

You need scales though for sure.

SoSideways 08-25-2010 08:05 AM

Quote:

Originally Posted by Slidin' Sam (Post 3606105)
SoSideways - Yes, the steering rack is off-centered. I believe you should have more steering angle when turning in the direction of the passenger...so to the right for you and to the left for me. I am not positive, but I believe the steering rack is off-set like that because of where the input for steering (ie steering colum) is located in relation to the rack. The d-max steering rack spacers are supposed to correct this (as well as give you an extra 7-8 degrees) and give you equal steering left and right.

That is correct.

I was getting a lot more angle when I turned my steering wheel to the right (passenger side) on my car, to the point where my wheel's inner lip hit the tie rod before hitting the steering stopper, which is all the way in just like the driver's side.

Again, while it might matter to others, at this point, I'm over it, but there is definitely more angle to be found in my setup, as long as I get either longer tie rods or one of those Dmax spacer things.

Slidin' Sam 08-25-2010 09:03 PM

Quote:

Originally Posted by SoSideways (Post 3606347)
That is correct.

I was getting a lot more angle when I turned my steering wheel to the right (passenger side) on my car, to the point where my wheel's inner lip hit the tie rod before hitting the steering stopper, which is all the way in just like the driver's side.

Again, while it might matter to others, at this point, I'm over it, but there is definitely more angle to be found in my setup, as long as I get either longer tie rods or one of those Dmax spacer things.

Do both!!! The spacers are cheap, and so are Ikeya Formula tie rods...their actually about the same price!

INeedNewTires 08-25-2010 09:55 PM

Any of you guys ever seen the Z33 outter tie rods? *hint hint*

swiftmini 08-26-2010 02:53 AM

Just get psm stuff when it comes out ;)

Thanks for the cofg calculator :) will try and get onto scales asap!

SoSideways 08-26-2010 07:17 AM

Quote:

Originally Posted by Slidin' Sam (Post 3607430)
Do both!!! The spacers are cheap, and so are Ikeya Formula tie rods...their actually about the same price!

I just don't really care anymore at this point.

Last night I decided to move my steering back over by 1 tooth, so that I can get a little more thread inside the turn buckle of the tie rod end on the passenger side.

Well, I ended up having to move the driver's side steering stop, because it wasn't stopping soon enough, and caused the driver's side wheel to hit the tension rod.

After adjusting everything, it looks like I'm good on both sides. I get maybe a little more steering if I turn to the driver's side before it hits lock, but we're talking like, one or two degrees, and I know for a fact that both wheels have about the same exact angle now when the steering wheel hits full lock.

So while aesthetically, the steering wheel doesn't have the "same" number of turns from left to right, but the rack is moving the same from left to right, so that's all that matters.

As a matter of fact, I might need to adjust the toe a little bit more, and that right there might get me that little bit more of turn on the steering wheel.

Passenger side is 100% completed last night. Just gotta dremel the LCA on the driver's side a little, spray bomb it, then bolt everything back up, and that side is done too.

!Zar! 08-26-2010 02:23 PM

Regarding the centering rack thing with the offset spacer, or even without it for that matter.
Quote:

Originally Posted by assassin10000

Basically:

1. Install spacer/adapters on right/pass side.
2. Turn steering wheel all the way to the right/pass.
3. Adjust the right/pass side tie rod end length for the amount of angle you want.
4. Turn steering wheel until right/pass side wheel is straight forwards. (The left/drivers side should have some pretty decent toe-in at this point)
5. Adjust left/drivers side tie rod until left/drivers side tire is straight.
6. Center steering wheel (at hub, or steering shaft, ect). Set toe (in or out as desired).

Done.

That seems like the best way.

SoSideways 08-26-2010 03:07 PM

That might work if you've never taken the rack off of the car.

I just put in a HICAS rack to replace my old worn out stock non-HICAS rack during this whole down time.

Slidin' Sam 08-27-2010 12:56 AM

Quote:

Originally Posted by SoSideways (Post 3608530)
That might work if you've never taken the rack off of the car.

I just put in a HICAS rack to replace my old worn out stock non-HICAS rack during this whole down time.

That might be interesting for you...some HICAS racks are pretty funky, but I am assuming its a s13 HICAS rack, so you might be ok...over here the s14's w/ HICAS and some of the skylines I have messed with have responded very negatively to certain mods...just kinda worried that you might have some drawbacks from it...but you may be perfectly ok.

zorak 08-27-2010 01:18 AM

The knuckles I have are like that one guy's from Japan who runs no sway bars, has 16s, ugly fenders, and like a light blue paint.

I can't wait to test them.

There is a post in this thread I think with pics of his suspension and an MS paint drawing. I can't find it tho and kind of tired of looking.

http://i967.photobucket.com/albums/a...t/P8260002.jpg

nieko 08-27-2010 01:37 AM

Those look like the Driftspeed knuckles.

but they copied some other company i forgot... lol

zorak 08-27-2010 02:44 AM

oh yeah i found the link in this thread to the one i was talking about

Get more steering angle

edit* oh yeah and the ones i posted are supposedly going into production soon. i think they sell for $200 plus shipping.

SoSideways 08-27-2010 07:28 AM

Quote:

Originally Posted by Slidin' Sam (Post 3609530)
That might be interesting for you...some HICAS racks are pretty funky, but I am assuming its a s13 HICAS rack, so you might be ok...over here the s14's w/ HICAS and some of the skylines I have messed with have responded very negatively to certain mods...just kinda worried that you might have some drawbacks from it...but you may be perfectly ok.

Yeah mine came off of an USDM S13 HICAS hatch.

I got the rear sway bar off of it too.




Front suspension completely bolted back up and nuts/bolts torqued to spec. Only thing I'm worried about is the driver's side FLCA still rubbing on the rotor when at ride height. It doesn't rub anywhere at full droop, but once I am at ride height it might. I'm hoping it doesn't, but I really don't think I'm going to take the spring off to check for clearance anymore... so over it...

DC Dan MAX USA 08-27-2010 07:07 PM

Quote:

Originally Posted by thefro526 (Post 3606279)
Dan, Have you had a chance to take any measurements of the angle you were able to achieve with that setup? It looks like you're well in excess of 55* on the leading wheel.

The suspension setup is impressive without a doubt. I can't wait until these parts are available for purchase.

Angle is 55 degrees (center to lock while on the lift) but the most unique thing is that we are achieving this angle without overcentering.

heres proof

http://www.gtfactory.jp/cms/e107_fil...2_p1070360.jpg


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