300zx's ELX work log

[KAinjection]

That was my thoughts on it too, simplicity lol. Worse case you can have a front set built up so you're not rushed with figuring out how to secure the sway bar ends.

At the time and since I have taken so loooong to get this setup together, it was the easier thing to do.

Thats to bad... Jim had no problems adding the sway bar tabs for both my self and Rob.. They worked out really well for both of us... Using a rear sway bar like the one you have or the mx3 design made the end links really easy to fab up... You should look into it for the future..

I may consider that later down the road, but first I want to work on something for the front for bump steer and roll center, especially since the rear was a something that could be noticed right away. Then maybe, just maybe I will finally be done with the suspension part and work on the engine/trans part. I have run out of things to change in the suspension, other then the front swaybar, there is nothing stock left on the car.

[crazycanadian]

Do you have any pictures of your front suspension set up? What are your alignment specs like? I am curious about what more you plan to do.

[KAinjection]

Sorry no pictures, I never took any when I installed the new control arms. Front suspension Is Jims control arms, rod end/poly endlink on the middle setting, and K-sports set on about 20 clicks from full soft. Alignment is 0 toe and -1.7 camber all the way around.

Plans involve building a new tie rod end that will be adjustable for bump steer and a little longer to allow the use of RX-7 ball joints. I plan on modifying RX-7 ball joints by removing the OE ball stud and finding a spherical bearing to go inside and have it professionally welded in to allow roll center adjustment, or just have Jim build me one.

Also FYI--- FC RX-7's have the same inner tie rod size and thread pitch as the BG/EC and Miata inner rods (10x1.25) allowing us to use FC bump steer kits and possibly rack spacers made by places like Mazdatrix and some others. Only problem is we cant use the adjustment stud in the kits since its tapered and designed to fit the RX-7 hole. The 7 has the tie rod end on the bottom while ours is bolted to the top, which is why I will just make my own and it will likely be cheaper anyway.

There is also something I will be checking at the JY tomorrow after work that has some potential for us, but its still is up in the air at this point and time.

[Mazda_Powered]

I like the sounds of the balljoint and bump steer setup!!! :O

[crazycanadian]

Sounds really interesting... Hopefully you can get lots of pictures...

What kind of caster did you get with your k-sports and jim arms?? I found with my car going from 3 deg to 5 deg of caster and running -3 camber up front helped a lot..

[KAinjection]

I realized I forgot my camera this morning, so I will have to run home and grab it before I go to the JY.

Caster, I have never checked it, but I think there is a way with my alignment tool I have, as I am sure I remember seeing it in the instructions.

[crazycanadian]

You'll notice much better turn in and mid corner grip depending on what your caster is set to.. How do you have your ksports set up? are you using the upper strut plate for more camber? or do you have it rotated 90 to max out caster?

[KAinjection]

Upper strut plate for camber. I will have to check the caster next time I have to do an alignment.

[crazycanadian]

Definitely do... If you are lacking in caster you can turn the strut plates 90 deg and use them to pick up more caster.. I found with my k-sports the upper bolt is slotted enough to get plenty of camber that way...

I have camber/caster plates now, but if I had to go back and do it over I would have just stuck with the stock camber plates.. used them for caster and then picked up camber down at the strut/knuckle...

[KAinjection]

Considering the price of the advance design plates that have caster adjustment, I may just do the method you have mentioned.

[KAinjection]

Went to the junkyard today to do some test fitting, and here is what I found:

Caliper mount comparison: Escort left and BG Kia on right

BG Kia knuckle with a miata caliper bolted on.

Comparison of tie rod position and you can see the difference in wheel bearing position.


Basic summery of important differences:
1-Kia knuckle has a larger diameter hub that wont allow other BG rotors to fit, but uses the same wheel bearing as all the others making it a matter of switching hubs to fit the rotor.
2-Kia uses smaller strut bolt spacing (66.88mm) vs the other BGs (71.9mm) but the width of the strut mount is the same.
3-Kia has the smaller ball joint stud hole
4-Kia tie rod mount is higher, but could be corrected by drilling out the mount and using a spacer.

The good news:
1-Caliper mounts look almost exactly like miata mounts and it uses a rotor of similar size (243mm) vs (234.7mm) 1.6 Miata. The rotors do have a different hat height at (42.6mm) vs (45mm) Miata
Regardless there is a chance that Miata brake upgrades could work here.
2- The placement of the wheel bearing on the Kia knuckle is higher in relation to the lower strut mount hole and the ball joint pinch bolt hole, essentially making this a drop spindle, allowing a lowered car to have better front geometry vs one with the standard BG knuckle, except for the part about the tie rod being worse.

Measurements on this part are the best I could do by eyeballing where the center of the wheel bearing was with my caliper:

From the bottom of the lower strut bolt hole to the center of the bearing:
Kia-87-88mm
Escort-94-95mm
Top of the ball joint pinch bolt hole to the center of the bearing:
Kia-88-89mm
Escort-77-78mm

I got both knuckles and plan on working them into my build in the future as I am pretty sure I can make them work.

Also started modifying the Kia BP upper intake manifold to make it work with the older style TB.

[concealer404]

What alignment tool are you using?

[KAinjection]

http://www.ebay.com/itm/DIY-WHEEL-TIRE-ALIGNMENT-KIT-CAMBER-CASTER-TOE-DIGITAL-GAUGE-QuickTrick-/321018521129?pt=Motors_Automotive_Tools&hash=item4abe31e629

Its works great, I have used it 2 times so far since I bought it a few months ago. You still need to use the strings and jack stands method in if you want to keep the front and rear aligned with each other and not be dog tracking. Quick camber and toe setting works great though and much more accurate then my last tool.

[concealer404]

Oh **** that thing is awesome!

I need to get stuff to align my car... was planning on doing the string alignment method with some nice Toe Plates and this: http://www.sears.com/shc/s/p_10153_1...%20Levelsmv=rr


So basically... string the car to get the front and rear aligned with each other, then just use that tool to set toe and camber, and to keep touching up the alignment each event? AWESOME!

[KAinjection]

For toe plates I went and bought a sheet of 1/8" aluminum, had them cut me four 12" squares out of it, basically like a floor tile. I then just smeared bearing grease between them. I would like to try something less sticky though as they dont really move very freely. Good but not great.

I used the tool to set my camber all the way around first, then I have 4 jack stands, 1/2" PVC pipe with holes drilled exactly the same for the front and rear pipes. Set the jack stand height so the string is about 1/2 way up the wheel or to the center of the axle nut/bearing. Make sure the string it tight and not sagging, then start on the rear axle and set the distance from the center of the wheel to the string and make sure it is exactly the same on both sides, then do the same on the front. After that your strings should make a perfect square around the car. Then you can start setting your toe and I recommend you use one of those stiff metal rulers instead of a tape measure.

Setting the toe with just the tool would not really work I find because you would basically be setting the toe and aligning the tires to themselves instead of to the center line of the car, not making the same adjustments on both sides and makes your steering wheel off as soon as you start moving. Best to use the strings and the tool.

Quick track adjustments though the tool will work fine by itself.