FWIW for you former Subie guys (like me), GT WORX is RCE. Same company, different products.

 

We are RCE. Glad so many of you like our Subaru products.

Good springs (low and soft is bad), rear swaybar (not too big), alignment, and the WL RCA kit makes a killer all around street set-up. The front swaybar is worth it too.

- Andrew

 

I'd love to hear people's thoughts on this, especially Andrew. (I could never test what I'm about to write about, since there wasn't an easy fix for the front roll center height of a 2G DSM; maybe you've had the back-to-back, all-else-equal experience that is needed.)

The math says that having a roll center below ground level will actually help with initial turn-in, but will come back and bite you later on in the corner (i.e., it will hurt steady-state handling more than it helped turn-in). Is this a case where the math is misleading or does this match your experience?

 

This. I was just at Infineon this weekend with a whiteline RSB on medium (stock otherwise). Unforunately my wheels with stickier rubber had a nail in it so I had to go with the crappy DD tires (Sumitomo's). Whoo boy, car's tail end would start to slide way too easily, although it was a good experience to help improve car control.

 

I find there is a lack of travel on the GT worx springs. They bottom out very easily.

 

The math is correct in theory...and mostly correct in real life. There are just many, many variables also at play and it is impossible to get a back-to-back, all-else-equal experience. I will say that the understeer can come in very early in the corner....early enough that i can see why people would complain of poor turn-in when the roll center is that low. The EVO X is definitely an interesting chassis with all it's compromises and techno-wizardry. Super soft, heavy, tall-ish COG, interesting geometry, but awesome diffs. Works pretty well but a lot of things to work on and a lot of different ways to fix it.

- andrew

 

My sister has the RCE Blacks on her car (GR STi), they have no drop at all (maybe like 5mm). there isn't anything like that for the X, the closes would be Swift Sports, iirc they drop less than an inch all around. for the record, the handling on the STi improved alot more after the RCE blacks (along with some whiteline stuff) than my Evo did after the GTWorx springs install. but then again, the Evo didn't have horrendous understeer to start with...

the main difference I notice in handling between the 2 (I've tracked and autox'd both) is that the evo is looser overall, it behaves more like an rwd car than an awd... My sister is in the same boat, she likes her STi handling better cause it feels more planted. but trust me, loose is faster, you just gotta get used to it.


I have GTWorx and I haven't noticed anything like that... I mean sure they'll bottom out quicker than stock, but I haven't had any issues...

 

Interesting. Thanks. I wonder, then, if a combination of Cheng/Milligan thinking (i.e., a below-ground front RC) and good old Chapman quotes ("even the worst suspension geometry can be fixed if you don't let it move") by not getting a RCK but running outrageous spring-rates. Tempting.

 

I'm not sure if that could be fixed with outrageous spring rates or not, but even if it can you're screwed anytime you're on a less than perfect track, which is almost every track in the US...

 

front sways are definitely costly to install.
if your on a budget just get springs and a rear sway.

i got the swift spec-R cuz i heard plenty of good things about it but still yet to install it. should have em installed this week or the next. i got the cusco front+rear sways but seriously its way too pricey, if its just the rears maybe try the perrin. they only have a rsb and no front thats why i didnt pick them.

aside from that good tires like wat every1 said. i think the stock ones sux.
i got the continental dws since thats the cheap all season tires cuz im on a budget too. no $$ for the pricey ones let alone a second set of rims for summer/winter

 

The issue, for me, is planning to run in an autocrossing class above Stock but below SM, which means lowered, but no RCK. We faced exactly this with the 2G DSM: we needed to drop the nose, but couldn't fix the roll center height. The only solution was Chapman's: even taking the lower front motion ratio into account, we ran front wheel rates that were about 1.5 times those in the rear. This got us better grip and less corner-entry push than the standard "logic" of moving weight transfer to the rear. Of course, it also turned the car into a snap-spinning sphincter-constrictor. I really don't want to go through that again, especially when the car is also daily-driven.

 

Chapman is what I call a "realist." For sure there are many drawbacks to that approach too.

With regards to front roll center height, it's not exactly that clear cut and perhaps I misspoke before. Roll centers and the roll axis are one way to look at things. It can get a bit more complicated.

Here's a fun read:
http://www.neohio-scca.org/comp_clin...Center2007.pdf

- Andrew

 

i reccomend springs as well

 

Yeah, I've seen that before, but thanks for posting the link. I find it rather annoying, personally, as it seems to say "what you think is wrong" more often than tell you what is right. But one of the key points is there: don't get too wound up about roll center height, because it's somewhat imaginary, anyway.

I can't post anything related to the Cheng/Milligan approach (i.e., purposefully low front roll center for turn in) but can say this: they had the fastest time at SCCA Nationals (autocrossing) again this year, so they know what they're doing. I can also say that thinking about the roll axis (even if some say it's imaginary) can be useful. The 2G DSM turned best with a low front RC and a high rear RC. The nickname for this approach to getting those cars to slalom was "stink-bug mode" (tm).

 

My 05 STi had Tein basics, sways and rolled on 245/45-18's. The handling was dreamy, but the ride was a little rough for being my DD. The best way I can describe it, is the car felt heavy. Not agile per say, just heavy. But the heavy feeling was SUPER stable on the mountain corners. It was easy to have confidence in power delivery, even though I would start getting sick to my stomach from the motion sickness if I kept my foot in it.

The 11 GSR, it's only at about 1k miles, and because of break-in I haven't felt it on anything technical, just some sloping fun high speed freeway goodness. I think the thing that throws off my confidence is a very slight amount of body roll, that starts to give the "off-center" feel. It then starts to FREAK me out when I feel the AYC start change the power up as the car starts to induce a little under-steer. It's the same feeling I've felt driving a 2wd pickup in bad rain when the back end starts to push a little when it starts to lose traction...but with the Evo, it's the AYC tracking the car into a neutral feel.

I can't wait to do some suspension mods and go to 265's on the rubber!