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

[codyace]

Originally Posted by DC Dan MAX USA

Cody, its all about getting the roll center and ackermen correct, and the advantage to drifters is steering quickness, angle, and drastically reduced ackerman

With that considered though, I'll put out a few thoughts of my own. These could easily be wrong as I'm not a super duper chassis guy, but do think I know enough (well, we know how assuming can work for me haha)

1. How are we to know if the stock Knuckle/setup is true zero'd ackerman in regard to a steering sweep. Could the factory setup potentially be negative, thus making less ackerman harmful to a degree (as in, super amounts of toe in to me would scrub itself to death, thus causing the car to push)?

While my LCA mod obviously adds more ackerman (KPI all of that stuff) to the factory setup, what I would really be curious is if it's adding more to setup that already has + ackerman, or if it's taking a setup that may potentially be - ackerman and putting it slightly to + ackerman?

2. To me, on a track car, I don't really ever crank my wheel 'so far' to either lock (the only places where I would, we're going so slow that it really isn't making a different) to see where there would really be a huge ackerman change...

...so with that said at a normal 'track' turning radius, wouldn't you maybe want some positive ackerman angle to help with a bit of turn in? I'd assume that with your turning wheel 'toeing out' into a corner helps to a degree vs hurts? I know you're still scrubbing the tire to a point, but IMO (or at least to what my preference is) I'd rather have a car that turns in sharp, as I can then maybe get on the throttle sooner on corner exit, and not worry about it oversteering so quicky.

Again, just thoughts out there. Even for a drift car I can't see how a ton Negative ackerman being beneficial as now the front inside wheel is toeing in while cornering...that just seems like it would cause front end push more than turn in...

(again, pardon my random thoughts)

Originally Posted by PoorMans180SX

PSM and DW guys get 45mm correction. Yours looks like... 20mm? Plus they give a nice bump in steering speed.

It's between 1.5 and 1.75 inches IIRC...so we'll say maybe 40mm?

In regard to Ackerman, see if my 'musings' above make any sense...I could be wrong, but it's maybe due to my interpretation.

[godrifttoday]

Originally Posted by Def

You can possibly pick up from their shop, but it's still my design that I have Mike and Juan do the machining for some parts.

Yeah they made that clear. Do not worry no ethical dilemma here

[Def]

For a track car ackerman doesn't really affect things much. Like Cody said, not much steering input in most corners to really build up a ton of angle difference.

That said, ackerman is mostly useful to keep the inner front tire at its optimal slip angle, which would probably mean negative ackerman for a high speed corner, but it would absolutely suck for slow speed corners.

I don't think the stock setup has 100% ackerman, but it's been a while since I messed with all the geometry. It was close to 100%, but a little bit off one way.

Around stock works fine on the track, and even more ackerman works fine on the track (maybe helps lower speed stuff a bit more, but higher speed stuff you unweight the inside front so much I don't think there could be a difference).

For a drift car obviously this all doesn't apply.

['97 S14 SE Turbo]

I think you may be a tad, just a tad, biased there.

Yes, a tab bit biased there. But nice work on the brake package. I don't follow that and didn't know about the double bleeders. I stand corrected.

[DC Dan MAX USA]

Originally Posted by s13silvia123

i've been wondering for awhile now if your knuckle mod will work on my SPL LCA.

It will work with any LCA, what made you wonder if it wouldn't?

Originally Posted by codyace

It's between 1.5 and 1.75 inches IIRC...so we'll say maybe 40mm?

In regard to Ackerman, see if my 'musings' above make any sense...I could be wrong, but it's maybe due to my interpretation.

Are you measuring between the ball joint and the knuckle to get that measurement? The question is what's the difference between stock length and yours, not overall distance.

Nissan got the Ackerman right for grip but...It's good to think about these specs, and you can see what actual change your alteration made by putting a straight edge on the wheels lip, and marking the angle per steering wheel half turns with tape lines on the ground (versus stock)

But originally your question was are the aftermarket companies knuckles worth the difference in money versus your DIY mod. If you are happy with your cars performance then maybe it's not worth it for you, but technically our grip spec knuckles are a better way to correct RC without side effects, and for drifting, the new knuckles are far better than DIY options.

[Def]

Originally Posted by '97 S14 SE Turbo

Yes, a tab bit biased there. But nice work on the brake package. I don't follow that and didn't know about the double bleeders. I stand corrected.

The comment about it being "the best" was more than a bit tongue in cheek. I'd gladly trade my BBK setup for a set of PFC forged monoblocks.

It's still the cheapest way to go for track usage though, even over stock, which was its primary design target. So it does that very very well.

[95KA-Turbo]

Originally Posted by DC Dan MAX USA

It will work with any LCA, what made you wonder if it wouldn't?


Are you measuring between the ball joint and the knuckle to get that measurement? The question is what's the difference between stock length and yours, not overall distance.

Nissan got the Ackerman right for grip but...It's good to think about these specs, and you can see what actual change your alteration made by putting a straight edge on the wheels lip, and marking the angle per steering wheel half turns with tape lines on the ground (versus stock)

But originally your question was are the aftermarket companies knuckles worth the difference in money versus your DIY mod. If you are happy with your cars performance then maybe it's not worth it for you, but technically our grip spec knuckles are a better way to correct RC without side effects, and for drifting, the new knuckles are far better than DIY options.

Yeah, mine was maybe 20mm over stock and I had to trim the shit out of my LCA to keep it from hitting my rotor. Even if the aftermarket LCA has less material, I would doubt you can get more then 22-25mms of correction on a DIY set up.

With just driving my car around on the street I noticed a huge difference with the Pro Knuckle mod. It feels way flatter and more stable, with much quicker steering input. I can't wait to test these things out on the track....I just wish you all had offered this stuff in 2009 when I was building my original DIY shit. I essentially wasted quite a bit of money.

[ch1873857]

ok. sadly i have not been able to completely keep up with this thread. i could sort through 84 pages of reading to try to find the answer. got 2 questions.

first. i managed to get my hands on a pair of R.Y.O. drift knuckles


i know nothing about them other than i got a sick deal along with these


about 1200 for both.. my question is, does anyone know anything about these knuckles? they are pretty rare and i bought them before the PRO knuckle came out from PBM which im still contemplating getting. since i bought pretty much everything else PBM carries..

i can tell right away that it wont help my roll center or ackerman probably. Pretty sure they will just help my angle. which is ok i guess, not sure which tie rods to use though as far as length is concerned. im still deployed so i cant play with it but it would be nice to have my ducks in a row when i get home even if that means picking up some pro knuckles. any help would be much appreciated.

second. has anyone heard or used these DME angled tie rods i guess instead off using spacers to lower the tie rod to parallel the angle the rods to prevent binding of the ball joint. these are fairly cheap at 110 for the ends and 110 for the inner. thoughts?

[bataangpinoy]

try em out, they seem like they'd hold up well.
the only thing of concern would be the added stress to the outer because of the slight angle..

how would you make it bolt up to the s13? are they the same PTC?

[ch1873857]

the ends? they are made for s13 so yeah i would assume they would. Ikeya Formula just brought some out. pillowball type. like 350 bucks though. may be worth trying but i hate being the guinea pig

[bataangpinoy]

Originally Posted by ch1873857

the ends? they are made for s13 so yeah i would assume they would. Ikeya Formula just brought some out. pillowball type. like 350 bucks though. may be worth trying but i hate being the guinea pig

excuse my ignorance. when i saw DME i immediatiely thought mitsubishi application. i should have read it more carefully.

[ch1873857]

oh no worries. you just confused me at first. wasnt sure if you were talking about the knuckles or the rod ends. ive never even heard of DME...

[Motary]

Well, here it is:

Wisefab kit for S chassis:

Video

65 degrees of lock and lower balljoint pickup point lowered 56mm!

Contact: contact

[95KA-Turbo]

Well that's pretty retarded they wont even show what it looks like.

[Motary]

I suppose all in good time?

Updated BMW kit is like this:

[PoorMans180SX]

Wow, ackerman adjustment, 56mm roll center, 65 degrees of lock? Wisefab looks to be killing it on paper. I'm looking forward to more videos!!

[95KA-Turbo]

Now people need to get to work on rear suspension geometry so we have like 5 options for that too, hahaha.

[godrifttoday]

Originally Posted by PoorMans180SX

Wow, ackerman adjustment, 56mm roll center, 65 degrees of lock? Wisefab looks to be killing it on paper. I'm looking forward to more videos!!

omg! omg!!!!!! lets wait for PBM to REPLY now....

[icedsole]

that wisefab kit looks silly. big angle is cool and stuff but i think that is too much imo


does anyone else feel the same way? can we share feels?

[ch1873857]

dont worry about that. i think its too much also. wheels almost 90. in the suspension world to much and too little of a certain thing is a bad thing. in this case i could definately having adverse effects. i couldnt even begin to explain why i think that but i agree with you.

[s13 loverr]

Wow, thats a great job on their part is it just me or do they have zero camber at full lock? I am super interested to see how these turn out! Paired with psm's tie rod spacers they could have crazy amounts of angle.

[ch1873857]

Originally Posted by s13 loverr

Wow, thats a great job on their part is it just me or do they have zero camber at full lock? I am super interested to see how these turn out! Paired with psm's tie rod spacers they could have crazy amounts of angle.

yeah crazy, stupid, useless amounts of angle

[IIIXziuR]

Guys we need a kit that delivers complete 90 degrees of turning angle.

They have not yet seen REAL backwards entry.

[Otto347]

Just throw some Omi-directional wheels on, save some time....

[swiftmini]

Personally I dont think that new kit has as much angle as they like you too believe!

Always looks like more with no bumper and clever picture angles make it look more!

Geomasters or pro knuckle for the win

I honestly reckon my geomasters have atleast the same as wise flab

[PoorMans180SX]

Wisefab kits are no joke guys. Who else do you know that 3d models the front suspension before they go about modding it?

Their 3-series kits are very well thought out and very effective in competition, I'm betting this kit will be just as good. It probably won't be as cheap as the PSM or Driftworks kit, but it will be just as good IMO.

[thefro526]

Not really digging the wisefab kit.

Not sure why.

[TheRealSy90]

Well I know now what i'm getting for christmas haha.

Originally Posted by 95KA-Turbo

Now people need to get to work on rear suspension geometry so we have like 5 options for that too, hahaha.

Apparently someone is trying to copy their design already so they blurred it out for now.

[Pantaloons]

Explaining the Wisefab Nissan kit - YouTube

im interested to see the kit

[articdragon192]

Originally Posted by icedsole

that wisefab kit looks silly. big angle is cool and stuff but i think that is too much imo


does anyone else feel the same way? can we share feels?

I dunno, looks pretty awesome.