This is the roll center, suspension pickup, and steering angle modification thread.

[mikerbike]

My Ikeya Formula tie rods weren't long enough. I made some spacers with KA cam gear bolts and Moog outer tie rod jam nuts.

[swiftmini]

I like your trick ^^^ its neat

Mine where also too short.

[mikerbike]

That's how I extended my stock tie rods when i extended my control arms. But I didn't want to weld to my shiny new tie rods. New knuckles. And I raised the front of my car almost an inch. I haven't been able to drive it angrily yet.

P.S. Is angrily even a real word?

[DJPimpFlex]

Originally Posted by mikerbike

My Ikeya Formula tie rods weren't long enough. I made some spacers with KA cam gear bolts and Moog outer tie rod jam nuts.

How long were your LCA's?!? I have zero problems with Ikea's and have tons of angle. Set up specs?

[Matej]

Run this style of rack spacer on both sides, and there should be no need for longer tie rods.

[Motary]

I have also thought about running two rack spacers, has anyone actually done this and not had any problems?

[frifox]

Originally Posted by Matej

Run this style of rack spacer on both sides, and there should be no need for longer tie rods.

was looking for a pair of those... where do they sell them?

[az_240]

^I think george (that's his username) is still selling them... Quality piece.

Running two might be too much...could overcenter. Spaces the tie rod ~1¼"

[KA240SX808]

Last time I checked he sold out and was trying to find another place to machine them cause who he was using wanted to up the price. IDK if he found someone or worked something out. But if he is making them again I'm down for a pair.

[travypoo]

Cor integration makes those spacers. With the slip on spacer on the I30 inners you koose about 5 threads compared to the teins. There is still a decent amount of.thread left over to fo.into the rack

[swiftmini]

Originally Posted by DJPimpFlex

How long were your LCA's?!? I have zero problems with Ikea's and have tons of angle. Set up specs?

You may have tons of angle but some peeps have retarded angle

Mine were too short from the moment i bought them. I have dw geomaster knuckles and homemade lcas. IIRC the lca is 390-400mm which is somewhere around 35-40mm longer than stock. Iam running 245;40;17 ad08 so as soon as i can drop back too a 215 ill be able to shorten the arms by 15-20mm ish

[swiftmini]

Originally Posted by Motary

I have also thought about running two rack spacers, has anyone actually done this and not had any problems?

could it not upset the steering? itll alter bumpsteer and ackerman IMO

Originally Posted by frifox

was looking for a pair of those... where do they sell them?

Nigel Petrie of Engineered Too Slide

Originally Posted by travypoo

Cor integration makes those spacers. With the slip on spacer on the I30 inners you koose about 5 threads compared to the teins. There is still a decent amount of.thread left over to fo.into the rack

Put the rods in a lathe and machine them instead of making them unsafe by running a spacer

[kristinachelsea]

Originally Posted by DJPimpFlex

How long were your LCA's?!? I have zero problems with Ikea's and have tons of angle. Set up specs?

I think someone borrowed mikerbike's fone and posted something of a sexual slur, earning him a time-out. Control arms extended ~37mm, rack moved forward ~28mm, knuckles pictured above, long one with all the ackerman came off, short one went on. They're about 3 7/8" from LBJ to TR hole.

Originally Posted by Matej

Run this style of rack spacer on both sides, and there should be no need for longer tie rods.

Kinda forgot about those. On my car, the tentative plan is to use offset rack spacers, only lenghten the control arms 25mm, and chop the knuckles to ~4" even. Until then, we are going to install the knuckles that came off his car.

[maverickmotorsports]

Sorry guys I haven't been making those in a while. My machine shop raised the prices on me and I haven't been making them since.

[swiftmini]

Originally Posted by Motary

Modifications me and my mate did on his car:

I just realised what you have REALLY done with these knuckles

You flipped the centre upside down like dw geomaster knuckle.

1.Iam guessing you made jigs??

2.Did you copy geomaster geometry?

3.Also the subframe up there ^^^ Any worry about flexing or anything, its pretty thinned out in places, i want to copy

4.Did you modify the chssis rails on the car to regain some clearance for the camber arms and camber arm brackets?

5.You raised it 30mm right, is that 12mm or so removing the bush and another 18mm cut away from the frame?

sorry for all the questions

[Patrick Bowering]

Originally Posted by Motary

I have also thought about running two rack spacers, has anyone actually done this and not had any problems?

I ran two last year. I had s14 lca, pbm knuckles with 25mm rc correction, moog s14 inner and outer tie rods. This was in my s13. I had no bump stops and was stopping when the tie rod hit the lca and the wheel hit the sway bar(st sway bars). my only problem which I didnt notice until after going to swap it all into my new car was that I bent the inner tie rods just a tiny bit because my rack had too much travel.


alignment was 3.6* camber 1/8th toe out. 7.2 caster level control arms

wheels were 18x 9.5 -5

[Motary]

1) Jigs to hold them in place yup
2) Geomasters raise bearing 25mm, these raise it 40mm, so no, these are better
3)If you are worried about flexing, you can add material to the otherside where you come some off. I'd personally make a new frame since this mod was very time consuming and if you're allowed to do this in a drift series, a custom frame could be legal too, for an engineer like you it should not be a problem
4)Chassis rails were not modified
5) It was raised 40mm, 12mm from bushings and 28 cut off, for more detail about this you can google 'engineered to slide cradle'

About the Xtrail ones, I installed my them on my s13 without any issues, they are with M14x1.5 outer tie rod end thread and M16x1.5 inner like S14 ones and they are 20mm longer than stock s13 ones.

[GKTECH]

Originally Posted by Motary

1) Jigs to hold them in place yup
2) Geomasters raise bearing 25mm, these raise it 40mm, so no, these are better
3)If you are worried about flexing, you can add material to the otherside where you come some off. I'd personally make a new frame since this mod was very time consuming and if you're allowed to do this in a drift series, a custom frame could be legal too, for an engineer like you it should not be a problem
4)Chassis rails were not modified
5) It was raised 40mm, 12mm from bushings and 28 cut off, for more detail about this you can google 'engineered to slide cradle'

About the Xtrail ones, I installed my them on my s13 without any issues, they are with M14x1.5 outer tie rod end thread and M16x1.5 inner like S14 ones and they are 20mm longer than stock s13 ones.

Wow, awesome work. They look great!

[swiftmini]

Originally Posted by Motary

1) Jigs to hold them in place yup
2) Geomasters raise bearing 25mm, these raise it 40mm, so no, these are better
3)If you are worried about flexing, you can add material to the otherside where you come some off. I'd personally make a new frame since this mod was very time consuming and if you're allowed to do this in a drift series, a custom frame could be legal too, for an engineer like you it should not be a problem
4)Chassis rails were not modified
5) It was raised 40mm, 12mm from bushings and 28 cut off, for more detail about this you can google 'engineered to slide cradle'

1. + 2. Ill be making mine from scratch with spherical bearings and dual caliper brackets. Not sure on geomasters but i thought they raised bearing by 50mm. I'm guessing they mean coilovers mount, relative to bearing, not the relationship of subframe to bearing.

3. I think your right. I need to make my own frame and my own rear knuckles. I have been looking alot at the japspeed and engineered to slide tubular frames. I need to pull my finger out and get on with it

4. Awesome. Just confused cose on engineered to slide s13 he has. But i think his is more extreme.

5. Awesome thanks

[conrad_s13.5]

agreeed,...motary, stuff looks great
:thumbsup:

[Motary]

Yeah ETS Nigel raised his subframe 55mm, my idea for making new knuckles for the rear would be removing bearings/bushings and making 'ears' like the subframe and use male rod ends has

Food for thought: excessive caster, yet car and driver are very successful



HGK racing lock kit for e46..

[swiftmini]

Originally Posted by Motary

Yeah ETS Nigel raised his subframe 55mm, my idea for making new knuckles for the rear would be removing bearings/bushings and making 'ears' like the subframe and use male rod ends has

Food for thought: excessive caster, yet car and driver are very successful

camber gain is amazing

when your going backwards the steering is useless. you NEED a higher grip level on the rear. if the front tyres are flat and making maximum contact patch giving more grip than the rear, then the car will just carry on looping round into a spin.

maximum front grip is for fast bends, twinning ect

mega amounts of lock is only usefull for massive entries in my opinion
I defo prefered trying to going backwards with excessive camber gain, feels poop with flat contact patch

I agree with the use of rose joints at the knuckle end of the arms. cheaper and stronger too make. probably easier too. My mate is coming over later and he is a solidworks genius so we will bash something out and see what we think. I have also got access to a pipe bender and a qualified welder. I have my own lathe and work in a cnc factory so shouldnt be too much trouble

EDIT: 55mm i wonder if he adjusted the anti squat and from the pics it looks like he kept the s13 frame.

[Motary]

It looks like the anti squat was not adjusted, for my own subframe I have S14 spec and lowest hole for spec that makes upper arms parallel with lower control arm.

I would also think that lots of understeer would help cars with big reverse entries, but then reverse ackermann and flat front wheels were added to the market making it so confusing.

I just noticed before posting this we have same amount of posts lol

[PoorMans180SX]

Very interesting discussion you have going here.

Do you guys really think that much correction is necessary in the rear? The front roll center drops MUCH faster than the front, and raising the rear too far above the front is going to give you some crazy understeer, as the roll axis vs mass axis angle is going to be way different.

Also, you are going to gain a TON of anti-squat doing that. You'll definitely need to change the lower arm angle.

[Motary]

The car where I performed such extreme mods had rc height of -300mm in the rear, the car is ridicilously low, rim tuck with 17 inch wheel



For us who don't follow rules correcting front geometry is easy by raising chassis points, heim jointed arms are very thin compared to oem bushings and using offset rack spacers to avoid bumpsteer

[swiftmini]

Originally Posted by Motary

It looks like the anti squat was not adjusted, for my own subframe I have S14 spec and lowest hole for spec that makes upper arms parallel with lower control arm.

I would also think that lots of understeer would help cars with big reverse entries, but then reverse ackermann and flat front wheels were added to the market making it so confusing.

I just noticed before posting this we have same amount of posts lol

Haha funny that we post same amount. all my posts are in this thread lol

Ackerman adjustment is also very good though. i find that my car can drift on a much bigger angle and at much higher speed. At the track if i decide that the front needs too be slowed down or sped up i just adjust my front toe slightly.

When i drift my mx5 i have too change my style od driving alot. its only about 100hp and is slammed on cheap coilies with a cusco diff and 7mm lock spacers. i have too keep momentum up and also need as much front grip as possible so i can get speed up before is start drifitng.

the s13 has enough power to just drive any old fashion

Everything i write is just my opinion it all comes down to personal preference and style. Iam sure guys like wisefab are doing what they need for theyre style of driving or competitions ect.

Originally Posted by PoorMans180SX

Very interesting discussion you have going here.

Do you guys really think that much correction is necessary in the rear? The front roll center drops MUCH faster than the front, and raising the rear too far above the front is going to give you some crazy understeer, as the roll axis vs mass axis angle is going to be way different.

Also, you are going to gain a TON of anti-squat doing that. You'll definitely need to change the lower arm angle.

Yes i totally agree. That much lift in the subframe isnt what i intend but i like too see how extreme you can go and see what all the ins and outs are before i start something.

I do intend on alot more front correction though, before i do anything at the back.

I want to move the front crossmember upward atleast by 30mm

[swiftmini]

Check out my rear wheel moving about in this video. its an old video. This is a contribution of bump, droop, roll, slammed car, standard traction rods, standard knuckles and s14 frame. Basically just poo!

swiftmini pembrey filler cap view.mpeg - YouTube

So if you could move the frame far enough too restore the angles ect to theyre factoryish settings. would the benefits of a better controlled dynamic wheel geometry, outweigh the negatives of upsetting the roll centres, roll axis Vs mass axis?

And here is an incar video, just for reference that shows my current setup. Please be gentle because its my first go on a fast track and the conditions were terrible, pretty down slippery but it was awesome fun. My car has perfect power to grip ratio in the wet i suck at changing gear, ill point that out before anyone else does

https://vimeo.com/43386900

geomasters
flush rear frame
my home brew flcas ect
-7* front camber
7* caster
rb25 @320hp

[Tearlessj]

Originally Posted by Teh Luckinator

goddamnit it took forever to find this picture:



so i plan on doing this (i'm assuming all 3 bolts are evenly placed, i haven't checked, do i have to drill shit?), except... flipped the other way. so basically the top of the coilover will sit towards the rear, and the inside, so i'll get more positive caster and still a little negative camber (also slotting top hole of the bottom bracket).

Is this the correct rotation I need to do, or do I rotate it so that it is pointing inwards?

Steps:

Center wheel in wheel well using tension rod
Rotate top hats
Use top hat adjustment for Caster adjustment.

Sound good?

[swiftmini]

well it depends if you want more camber or less camber. pointing in will give more camber, pointing out will give less camber EDIT: both will give approx same caster

[swiftmini]

tubular subframe inspiration/pawn

rear


http://a3.sphotos.ak.fbcdn.net/hphot..._2705617_n.jpg

front




i think its relative

Ps Trela runs his own design knuckles on the s13.5 ^^^ and has mid mounted jz and has semi space framed rear end i believe