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Discussion Starter · #1 ·
So, I have decided my next mod is the correct the dreaded bump/torque steer you acquire when you lower an RSX. I had a near-death experience on my way down to North Carolina (from Connecticut).

It was wet out for maybe 80% of the drive down to NC.. 40% was crazy down-pours where i was in a 70MPH zone doing 50MPH. But everything had seemed to dry out once i hit West Virginia. maybe a little damp, but probably only in the recessed areas on the highway where people indent the road.

there was this junction.. which was marked 40MPH.. i took it at about, maybe, 46MPH? Nothing too terrible.. but i hit a bump midway around the hairpin-esque turn, and it sent me in a spinning frenzy.

there was a guide rail to my left, and a ditch to the right. and a row of trees maybe 40FT down the road. So here i am fish-tailing like a mofo, pumping the brakes, turning into the turns, and basically avoiding the concrete doom that was to the left of me. I see the ditch to my right, and it is just grass.. so when i see it in front of me.. i FLOOR the gas in that direction. (I can't emphasize enough my choices of a trees, concrete, or dirt) So i end up in probably 6in of mud and grass. But my car was stopped. And in once piece (popped my front bumper off a little, but nothing that i couldn't correct when i pulled over)

SOOOO.. here is my question. Since that has happened, how can i ELIMINATE my bump steer? I have the coils already set stiffer in the rear (4 clicks stiffer). And im going to be ordering the 0857 tie rod, and bracket.

is there anything else that i can do to prevent something like this happening again? (other than taking corners at designated speeds)

Cliffs:
- Road trip from CT to NC.
- Took junction ramp maybe 6MPH too fast (it was slightly damp)
- Hit bump mid-way through.
- Fishtailed 3 times before flooring it into a ditch (my only choice)
- Landed in the ditch.
- Curious beyond inverted tie rod ends, and steering bracket, how to correct bumpsteer?

Thanks guys :D
 

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stiffer in the rear? that's a problem
taking corners at higher than designated speed? that can posibily be a problem if you don;t know what you are doing
pumping the brakes... why? ABS is there for a reason
tires?
alignment?
driver?
etc
 

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Discussion Starter · #3 ·
Well the tires are fine (just bought some kuhmos not even 4 months ago), the alignment is perfect (just had performance alignment with sandbag, and 4 corner balance).. i also kart all the time, so i def know how to drive, thus my corrective measures.

But i heard stiffer in the rear is how it should be for better control? or so the guy said after tuning my suspension.
 

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1st off, "Bumpsteer" has next to nothing to do with bumps in the road.

2nd, Instability over rough roads = Suspension too stiff for that road. as in spring rates too high & damper rates too hight.

3rd, the way you have your car setup promotes oversteer over stability (Higher suspension frequency on the rear tied in with stiffer dampers on the rear). Added to the probability that the roads were at least a little slick = you needing to drive well under the limits of what you drive when its totally dry out. Remember, well handling = unstable.

3th, Once this car starts to oversteer, doing any thing other then adding in throttle and counter steering is just going to make the oversteer worse. so that triple fishtail could be considered driver error. Live and learn. Just don't pump the brakes next time.


So, buying anti-bumpsteer parts, in this case, isn't going to stop what happened from you from happening again.
 

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Discussion Starter · #5 ·
1st off, "Bumpsteer" has next to nothing to do with bumps in the road.

2nd, Instability over rough roads = Suspension too stiff for that road. as in spring rates too high & damper rates too hight.

3rd, the way you have your car setup promotes oversteer over stability (Higher suspension frequency on the rear tied in with stiffer dampers on the rear). Added to the probability that the roads were at least a little slick = you needing to drive well under the limits of what you drive when its totally dry out. Remember, well handling = unstable.

3th, Once this car starts to oversteer, doing any thing other then adding in throttle and counter steering is just going to make the oversteer worse. so that triple fishtail could be considered driver error. Live and learn. Just don't pump the brakes next time.


So, buying anti-bumpsteer parts, in this case, isn't going to stop what happened from you from happening again.
Thank you very much, that was VERY informative.
I am from CT, which has tons of icy roads in the winter. and i guess it was instinctual to pump the brakes, since im assuming, in icy conditions that is where it works? i learned it from my mom, she is probably wrong.

So would you recommend setting my coilovers to a softer setting on both front and rear? or softer rear, stiffer front? and what should i tackle to eliminate this situation from happening again?

thanks a lot, this shook me up a lot.
 

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Your mom learned how to deal with ice in a car without ABS. Pumping with ABS will just mess up what the ABS system is trying to do. so Ice or not, you shouldn't pump the brakes in this car(or any car with ABS), ever.


as far as setting the car up, well... "optimum" settings for Wet & low grip situations will be drastically different then the "optimum" setting for dry weather. In low grip environments, rain Ice & snow, you want to have your suspension as soft as possible. So in the winter, it would be beneficial to run your dampers substantially softer then in the summer months. It would be nice to be able to change out springs to something softer... but thats a bit over the top for most people.

Just a tip on tuning with dampers 101. the end of the car that has stiffer valving is going to be the end of the car that tends to lose grip 1st in a turn. For handling, given that this car tends to understeer, that means we tend to run the rear dampers stiffer then the front.

So, remember this. Soft = Grip, Stiff = Slip. Tune accordingly.
 

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I've heard that concern before... and my only thought would be why would the damper Mfg give you the ability to set the damper to a stiffness level that would damage that damper?
 

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Just a couple of comments in addition to the excellent advice given above. If your coilovers are adjustable height you might raise the car 1/2 inch. Bouncing off the bump stops in a corner can cause instabilities. Also, despite your beneficial experience in the karts you need to keep in mind that the karts are unsprung, rear wheel drive, and balanced front to rear. As a result they respond completely different than the front wheel drive, sprung, nose heavy RSX. As was pointed out above, the response to oversteer is different in the RSX than in the kart, keep that in mind. What spring rates and anti-roll bars do you have in the rear, make sure you aren't too stiff in the rear for the conditions you drive in. Also, what were your tire pressures. Tire pressures in daily drivers are often overlooked. Tires loose pressure over time and if you rear tires were low that would have contributed to the oversteer incident, particularly in the wet. Check your tire pressures at least twice a month.
 

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Discussion Starter · #12 ·
Wow, this is excellent.

I set all 4 tires to 50psi. I overfill slightly for better duel economy.
also, i only have my car dropped 1.75" front, 2" rear, to level it out. (Like i said, i had it tuned.. and the owner of the company used to have an RSX, so compared the drops a little lower than the aspec kit.

Great advice guys, ill take it to heart. if i could give rep, i would. So someone please rep these guys!
 

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50psi !!!!!!!!!
you loose so much grip with that much pressure!
that's not over filling "slightly"! it is slightly over 50% above recommended pressure!
i would suggest dropping the pressure to 40psi or below.
 

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woah, 50psi? That's even higher than what I would use on my tires when I autox when I want to LOSE grip. You should be running around 32psi on the streets to let your tires grip. If you're concerned about fuel economy, maybe go as high as 35-ish, but 50psi is just nuts! Now I'm definitely not surprised by what happened. You somehow tuned your car perfectly for having the LEAST possibly grip on a dry road, let alone a wet, slipper one.
 

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Yeah, when I said check your tire pressures I meant within reasonable specs. Maximum range for street should be 32-36 psi front and 29-34 psi rear. If you want best fuel economy and traction use the high side if you want best ride quality use the low side. 50 psi is nuts, overpressuring a tire will lose as much traction as underpressuring and the tire breakaway in a skid will be much more abrupt. If you were running 50 psi at the time of the spin I think we've found the problem. Also running high pressures will cause rapid wear of the center of the tire tread.
 

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Discussion Starter · #16 ·
But my tires say 45 psi?

I will drop them down tomorrow! now that i think about that, that is most likely the culprit! I feel stupid now.
 

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The 45 psi he's looking at is probably the maximum operating pressure the tire carcass was designed for. This would be the maximum pressure you would use, if for instance, the tire was on a vehicle that was pulling a heavily loaded trailer or some other heavy load. It is not the recommended tire pressure for use with the lightly loaded rear end of a 2700 lb front wheel drive RSX.
 

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Sorry to say but I blame driver.

I just did my first HPDE in the rain last saturday running BuddyClub RSDs + nearly bald Hankook RS-2 (about only 25% of treadwear bar remaining, might be corded soon) + cornering speeds of anywhere between 40-77mph during thundershowers I had very little problems.

I think pumping the brakes did more harm than good.

Good job on accident avoidence though. Most if not all serious damage or personal harm was avoided with some smart thinking.

Hopefully it doesn't happen again.. scary incident for sure.
 

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But my tires say 45 psi?

I will drop them down tomorrow! now that i think about that, that is most likely the culprit! I feel stupid now.

Tire psi is determined by vehicle weight... not by the markings on the tire. Thats just the maximum allowable.

The proper tire psi for your car will be marked on one of the stickers in the driver side door sill, and should say something like 30 - 31 psi.
 
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