Hey all, this is my first thread.

I've been doing research on the differences in the rear suspension setup of the AP1 vs. AP2 (i'm sure there's a billion threads).

There's a pretty decent price differential on AP1s vs. AP2s and I was wondering how easy it would be to modify the AP1s rear setup to match that of the AP2 and correct the "twitchiness" that they're known for.

Who makes decent aftermarket toe links and for how much? Is that all that's different that affects the rear suspension twitchiness or am I over simplifying and there's more to it than just that?

Thanks for the help. I'm trying to decide between an AP1 and AP2, and this is the main thing steering me away from an AP1, but if it's easily correctable with reliability, longevity, and at a reasonable cost, then I might swing for an AP1.

 

The main difference betweens ap1 and ap2 are the springs rates and sway bars. Search for that

 

Well, according to this, it's more than just that - those are easily remedied with coil overs, but suspension geometry is another thing...

"We chose our S2000 as a project car for its handling prowess. With multilink suspension and a 50/50 weight distribution, the S2K has all the right stuff to carve corners with. AP2 S2K's like our car have revised rear toe link pick up locations so they don't exhibit the twitchy at the limit cornering issues that the older AP1 chassis has. What's good can always be made better so we decided to spend our efforts in improving our car's suspension in the next round of mods."

"The S2K was released in two versions, the AP1 which was built from 1999 to 2003 and the AP2 which was built from 2004 to 2009. The AP2 was a more refined car with a bigger, 2200cc F22C1 engine, revised closer gear ratios, improved syncros to eliminate the AP1’s troublesome grinding and most importantly, revised rear suspension geometry to give some toe-in under roll which fixes the twitchiness associated with the early AP1 S2K’s. This is not a big deal as the rear geometry is easily corrected on the AP1 with aftermarket toe links."

http://www.motoiq.com/projects/project_honda_s2000.aspx

It might be easier to just pick up an AP2...

 

What is your application? Are you going to be daily driving it or tracking it? I've tracked my stock AP1 a decent amount and have found that being very smooth with the inputs gets rid of the "twitchy" behavior. Maybe it's the twitchy driver causing the car to be twitchy?

Regardless, the AP2 rear subframes are different and I think the AP2 control arms are slightly different, as well. Don't quote me on the control arm part...

Rear "bump steer kits" are available, Megan, T1R, J's, but there are several reports of the outer hardware failing while on track. By lowering the outer pivot point of the toe link, you're effectively increasing the loads through the fasteners that attach the outer end of the toe link. Search around and you'll find the threads talking about BSK failures.

Cheers

 

I'm just shopping around right now. I really like the build of that AP2 in the article - I'd like something that's a bit more oriented for track use (as I plan to do around 10 HDPEs or so a year), but still somewhat friendly for everyday driving - it's not gonna be a trailer only car just yet.

Based on what you've said about reliability, I think it's probably best that I shop around for an AP2. Thanks

 

I have the Megan BSK and I know of at least 4 other frequent track guys who also have the same piece installed for over a year.

They were under $175 and at that price you can change them out if you were to fear them breaking.

It definitely cures the "twitchiness" that you can experience.

 

Sorry to revive a dormant thread- but for the OP, I can guarantee that the MotoIQ project S2k will see more than 10 track events a year. Trust me. Khiem was my college roommate- he was at the track all the time, and is still out playing on a regular basis.

For something that's livable on a daily basis but still track ready, I think his setup is quite close to what most people on this site would consider ideal.

 

I see, good to know. The MotoIQ S2K was run at Buttonwillow (my favorite local track) for the article.

I plan on doing a similar build over the course of 3 years. But first, I need to get a car. I've done enough posting here to know that I'm most likely going to get a 2006.

 

Oh- thought you had a car already! You should definitely start there first.

 

Well, i finally sold my GR STI and am slowly selling the left over parts, so that was actually the biggest hurdle. I can start shopping for one as soon as i find some time (i might wait until December/January and hope the weather/season drives prices down a bit).