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This is more for people who are suspension fanatics. I got a civic that I finally got good tires on with a (eye ball) dialed in suspension. Ride is smooth but at around 80-100+ the car starts to get squirly. Wheels are balanced aligned and suspension is measured and weighed but the car just likes to wander though not from any mechanical deficiencies. I pose the question out there to hondaland, does anyone have any advice on how to increase body rigidity/stability at higher speeds?

i got the basic stiff stuff tie bars sway bars and lowered with kyb yellows. is there anything else I am missing that can help?

whale tail spoilers, although effective in attracting a whale mate, are not effective in this scenario so please no fake and the fiberglass recommendations.

 
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try to find a shop that will take car in just for measuring the suspension and see where do you stand right now in suspension numbers? at least that should clear you of any suspicions on your own work, for starters... just in case this is the first time you do that, of course...
OK, Ur senior member, it was just a note... shutting up now.

 
Rep Power: 222

haha you've never been around long enough to know everything

i had each corner weighed at Orlando Speed World and its as closed to balanced as it can get. I guess what I'm saying is I'm getting a metric **** load of lift in the rear. Do rear diffusers actually work?

 
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In a word, Yes.

 
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OSW woot! i find at high speed, cross winds really push me all over the place. it could be that.

 
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Stiffer springs would help but the ride sucks at slow speeds (you gotta give one up for the other)but if your plannin on doin that speed constantly (like say on a race track) they make the car handle very nice no squirrly at all

 
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i have eibach ground controls on koni yellows

 
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What would be the alignment numbers you are running? that did wonders in my miata and civic as well and could work as starting point?
Sorry, really don't know your background, but if you can you could go to some of the autoX or track day or HPDE and if there is a guy with a similar civic to ask what numbers they do recommend? that did work for me previously.
That's in case you are not much in the racing environment.

 
Rep Power: 367

geez, i am being dumb again... from your profile:"SCCA North Florida Chapter. Porsche Owners of America. "
geez, post your background, although it should be kind of evident since it was a good and intelligent question, different from the normal ones we see here like subjects only stating "help Meeeeee!"
sorry again... couldn't help...
really shutting up now...

 
Rep Power: 320

you can get stiffer brushings if your talking about getting rid of the wobbley feeling at higher speeds. Should help, but it'll just feel that way mainly because of the lighter weight.

 
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yeah im starting to think the weight is having a lot to do with it. I could use some stiffer bushings in the steering rack for sure the steering wheel is kinda getting mushy especially at speed.

the light weight sure has something to do with it of that i'm convinced. i guess my next question would be to ask, do any of those aero-crap devices they sell everywhere (canards spoilers and diffusers) actually work? is there anybody that uses those and had good results?

last thing I want to do is add a whole bunch of weight BACK into the car. I've worked really hard to drop as much weight from my coupe as possible

-air bags (complete removal D & P and wiring harness and brain)
-spare tire/jack
-lighter wheels
-lighter engine parts
-lighter mounts
-lighter exhaust parts
-dust shields
-splash guards

maybe i've dropped 100 or so lbs?

 
Rep Power: 320

I'm not sure...no real way to really tell if the carnards and diffusers work without a wind tunnel.

I would just leave it as is, just because it feels little less stable at high speeds, doesn't mean it is. No point in giving up acceleration and mpg for speeds that you probably won't hit often.

I know in my mercedes going 135mph feels about the same as my integra did at 80mph. Anything below 120mph it feels like going 45mph in my gsr. Then again my mercedes weighs 1000 lbs more then my gsr did.

 
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i'd agree with that. Ze germans make heavy cars for that (and other) purposes. My 944 was a tad heavier then my civic roughly 2500-2600lbs and it was solid to 150mph and the aerodynamics of it would squat the rear end as you got faster.

I upped the front tire pressure a little and it helped get more bite in the front (slightly) but it still feels kinda finicky.

Track aside, I cruise at 80+ daily often going to 90-100 for several minutes over about 20 miles of I-75 round trip daily so I'm at speed for quite a bit compared to what most people do. More then anything it's the cross winds that push the car around but I can feel loads of lift coming from under the car it almost feels as if the rear end wants to come completely up.

Is there anything on the market for our cars to cut underbelly lift? Like the underside diffusers available for the s2000? i searched on google and found some made at home stuff but nothing substantial. Anybody know different?

 
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my friend's school has a wind tunnel. It's in virginia though and I wont be there till August

 
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try to search in the racecar engineering site and magazines? They do have a lot of aerodinamic articles.
http://www.racecar-engineering.com/
or make a homemade flat under panel? i believe there were some article somewhere about cutting the underside of the rear bumps of a miata to allow for air flow instead of re-circulation in the rear bumper, thus reducing lift in the rear? I think it was not very visible from the outside to cut it out. Was that grassroots magazine? can't remember...
just my 0.02 cents, i am not an aerodynamics expert.
If you were concerned about the fronts, the splitter article would help, there are some articles on using front splitters adding to front stabilization, but they are prone to hitting the ground easily.

 
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went to a machine shop and began chatting with some of the fellas there about developing a under belly pan to cover the front engine bay and the rear area from about the fuel tank to the rear bumper to cover the under side similar to how F1 cars are set up

 
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http://www.ziptied.com/forums/index.php?topic=7879.675

good articles on the topic but i think it's too much for just some bullshit commute honestly. Maybe if I go back to SCCA it's something I'll do

 
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found the article. Just take a look, it could be interesting.
http://forum.miata.net/vb/showthread...ng+rear+bumper

Since our bumpers are not closed as a miata's, you could try to look at some way to make the air exit from the bumper someway?

 
Rep Power: 320

maybe just try retroing a accord under body shield. I thought the civics came with them stock already, but if it doesn't. Then I agree it will make a difference. When i had mine off on my mercedes i could feel the front end lift as i hit 65mph+. When i put the shield back on, that lift feeling was gone.