I'm having the car undersealed in a few weeks, taking the opportunity to drop the subframes and suspension and uprate/refresh some items while I'm at it.

This currently includes powdercoating the subframes and all control arms as well as fitting a full set of Ballade Sports spherical bushes.
The car is an MY05 AP2 on 74k miles, running AR-1 semi slicks on OE wheels and Ohlins DFVs with the Swift 13/11 F/R springs
It's currently dropped 20mm and is used almost exclusively for hard track work, with a view to racing in years to come. Next year I'll also change the wheels to a square 255 setup and likely swap out the ARBs to just a front Eibach, pending further research and testing...

I've done some reading RE ball joints, roll centre adjusters and bump steer kits but am not sure what is recommended for a track-based setup with my accompanying mods.

Questions:
From what I have read, am I right in thinking there's an upper ball joint on the upper control arm, and a lower on the hubs; same for front and rear?
Given I'm having all arms powder coated, I assumed I'll need the OE ones removed/replaced regardless - with my other mods/setup should I be looking at adjustable aftermarket replacements or is this not necessary/recommended given the modest drop in ride height and fairly good OE adjustability?
Should I also be looking at bump steer and RCAs whilst I'm at it, or not necessary?

Thanks in advance...
Rob

 

Front ball joints are on the UCA and knuckle.
Obviously the tie rod ends as well.

Rear ball joints are on the UCA and knuckle and the toe arm. Think of the toe arm as a rear tie rod end.

There are a million ways to put adjustability into this suspension and they all have their pros and cons.

I would NOT recommend adjustable rear toe arms.

For camber, the idea with possibly least cons is to use a hardrace UCA. The front of this car benefits from camber adjustment. The rear, you should be fine with stock stuff.

For lesser cost, companies do sell press-in adjustable upper ball joints that go into your stock arm as well. If you buy SPC's newest offering (black booted ball joints), you will absolutely want to remove the boot, wipe out all the original grease, and replace it with a more suitable grease.

You can use lower offset front ball joints too. Some are adjustable...some aren't. I don't love the idea of using an aftermarket lower joint for safety reasons...but my Hardrace ones are holding up really well. Hardrace make really nice stuff. If you use them with a RCA plate, I'd recommend getting rear RCA's as well.

I recommend keeping as much of the stock stuff as you can.

There aren't any aftermarket "oe" upgrades for ball joints and tie rods. The best overall part in the world is still the geniune Honda ones you'd buy at a dealer/come on the car. So...don't blindly replace parts.

Additionally, its a good idea to seam weld your UCA mounts on the chassis. But do not do this if you plan to use the car in road salt.

If you're really going to put this thing thru hard/serious track use...consider using the WiseFab kit as a whole. Its pricey...but it does give you better geometry and strength as compared to stock or stock replacement. But..again....probably not brilliant for road use or salted road use.​​

That's the general idea.

Good luck. Feel free to ask more specific questions.

 

You likely need more, but as a note, with the amount of drop you have you "Should" be able to get -2.5 degrees of camber with stock parts. Mine is at -2.6 all around on all stock adjustments with roughly the same amount of drop. But, running more grip you likely will want more camber anyways, just throwing that out there.

It seems like some of the adjustable ball joints in the rear are correlating to broken control arms, possibly due to the fact that they clamp in vs press fit and putting more strain on that area of the arm. I do not think that is 100% proven, but there was a thread where folks were seeing cracked or broken arms and I believe they were all using adjustable ball joints similar to the SPC design. Go search that and make what you will out of the discussion but worth looking into.

 

I thought this was already done on AP2's? I know the AP1 has the issue of the OEM welds breaking loose on the front UCA but thought that this was fixed in later models? I say this because I am pretty certain my friend found the TSB for this and took it to his person when his broke to ensure it was done per that and was still class legal. Mine are fully welded but the previous owner had it done so I never looked too deeply into that.

 

Thanks for the feedback. I've been reading through various threads on the forum today and come up with similar findings, namely:

On the front & rear upper control arms, you can opt for adjustable ball joints that allow camber adjustment but the likes of SPC seem prone to causing snapped control arms. This is possibly due to excess stress via altered geometry? See https://www.s2ki.com/forums/s2000-br...l-arm-1172212/

Honda don't sell replacement UCA ball joints; they only come as a full arm as they don't recommend re-pressing bushes and joints. You can replace lower joint with Honda OE though.

Lower ball joints can also be combined with RCAs to correct roll centre adjustment if/when lowered. Ball joints can be normal (i.e. symmetric) or offset to also allow fixed camber adjustment and additional track width. The likes of Buddy Club may even offer some adjustment, but it is not generally recommended to use these as adjustment points.

Roll centre adjustment is covered in lots of detail via:

• https://www.s2ki.com/forums/uk-irela...stion-1141445/
• https://robrobinette.com/S2000OffsetBallJoints.htm and https://robrobinette.com/S2000RollCenters.htm
• https://www.s2ki.com/forums/s2000-br...ussion-844348/

Roll centre adjustment applies to both front and rear independently.

Finally, bump steer kits are also commonly compared with RCA but remain mutually exclusive of one another; see https://www.s2ki.com/forums/s2000-mo...joint-1187995/

For anti-bump steer, you can use tie rods or spacers - not both. Again, this needs addressing for the front and rear.

Assuming my understanding to be correct, and given my planned setup, I'm leaning towards:

• Front bump steer steering rack spacers
• The rear bump steer is, according to Ballade, accounted for within their spherical bush kit: "The Spherical joint used for the rear Toe Arm also does double duty as an Anti-Bumpsteer kit to reduce snap over steer"
• Hardrace front and rear UCA ball joints (given no OE option)
• Hardrace front lower offset ball joint with RCA (to provide >2.5 deg camber)
• Hardrace rear lower symmetric ball joint with RCA

This will be combined with:

• Full Ballade Sports spherical bush kit (all 22)
• Spoon uprated engine/trans/diff mounts with rigid subframe and steering rack collars and engine mount rings
• Ohlins DFV with Swift 13/11 F/R springs on a 20mm drop (standard cups) - already fitted
• 10mm axle spacers - already fitted

Brakes are already addressed with full ducting front and rear, APR backing plates, braided lines, Urge & Girodisc front/rear two-piece discs with Typ200 fluid and race grade pads
Tyres are currently Nankang AR1 semi-slicks on standard 17" MY05 alloys; to be replaced with a square 255 setup next year once this next round of work is done

Things I'm still not sure on are:
- Do I still need to account for ball joints on the toe rod ends and rear toe arms with OE replacements on top of the above?
- With a modest drop, should I concern myself with RCA at all

Cheers,
Rob

 

I do not think you need aftermarket RCA.

Your OEM tie rod ends and toe arm ends/joints should be fine assuming not worn badly.

I think the broken control arms may more around stock joints pressing in with adjustables bolting in and putting clamping force on the area not meant for that type of part. But hard to say, that is just one theory.

The lower rear balljoints are also not supposed to be pressed out (They do not even have a flat spot for pressing them out of the knuckle). But you can buy non honda replacements and plenty have changed them. They had to modify the cup on their ball joint press to sit on that area of the knuckle though since it is not flat. Not sure I have ever heard issues of doing this.

 

Its improved on the AP2. The mount is tucked under another sheet and there is a small cross brace. I still welded mine up. No clue what tyre I'll use down the road.

Your plans look fine. Just make sure you're fine with clearancing your fenders for all this stuff.

I don't think the RCA is all that beneficial with a 20mm drop.

I like my ride height low. So...

 

Yep, the AP2's front control arm mounts were re-enforced with success to seemingly normal street/track type cars. I don't recall seeing any front control arm mount issues for any normal HPDE car. I believe for track dedicated cars on R-Comps there is still some concern.

 

Oh, I guess I thought they just seam welded it Probably not a bad idea that you did though. Any extra protection from your wheel laying flat in the middle of a turn is good! My friend just noticed his car started handling like crap at an event. Took it home and pulled the wheel to see only the bottom of the mount bracket still connected. So he dodged a bad situation there!

 

curious about how you got to -2.6. Do you happen to know what your centercap to fender lip measurement is? Thanks.