Fixing corner grip on bumpy surfaces?

kannibul

The Z seems to hate bumpy surfaces, even more so on corners - a great example would be highway interchanges.

Seems there's always a bumpy interchange ramp, at least in Tulsa, that if you corner even at the posted speed for the ramp, will still toss your car around - where you can feel it lose traction and move outward a few inches at least.

I know my truck used to have a problem with this, but that was due to blown out shocks and worn out tires. Replacing both of those, fixed that problem.

My Civic and my Truck (and definately my motorcycle (not a crotch-rocket)) handle uneven cornering surfaces better than that Z...which is unexpected, to say the least.


So, how does one go about fixing this?

import111

Maybe you have too much toe in the rear. That can cause the rear to get really sloppy, especially on bumps. Also too much tire pressure could cause that issue also.

kannibul

Tire pressure is good. Rear Alignment toe is something like .01 according to the alignment paper I had.

I've misplaced it so I don't know the other info right off...

tooohip

KW V3's have fixed that problem for me. ;-)

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Modshack

This is generally the result of shock tuning..

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bullitt5897

I combat my issues with different lines and throttle modulation I found that with a lol more gas the backend settles out. Or should I say steps out a slight bit but it's very smooth when it does.

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vpn2001

I had the same problem with my S2000. It was due to suspension geometry. A couple of aftermarket manufacturer came out with an anti-bump steer kit. Hopefully someone will have one for our Z.

kannibul

I will say this much for it, you definately FEEL the G-forces more in this car than anything else I drive...it's odd and I can't explain it - but when you corner in this car, you feel yourself being thrown harder...

At least I know it's not uncommon.

RCZ

This is all bound and rebound + spring stiffness and how they work together. Get a set of good coilovers and voila.

kannibul

Any recommendations?

I like the stock height, with Tulsa roads I damn near need a lift kit...lol

It'd be for street use too...

kannibul

Disregard previous post

Found a relevant thread...

RCZ

What you are feeling is a car with sticky tires and a relatively soft suspension. The car leans and rolls into the corners because the suspension isnt stiff enough to counter the load. That lean makes you feel like you are building higher g-forces when you aren't.

You also can't just throw a stiff spring in there with the stock dampeners because they arent designed to work with it. The car will become uncomfortable to drive and very skittish and nervous over bumps.

Depending on what you do with the car...you can opt to get a full coilover system...If you are looking for something comfortable and good, get the KW V3's.

Will do and glad you searched for your answer.

kannibul

Yeah, KW V3's are what I was thinking.

Then I saw the price, and figure that's a "later" item. Exhaust is next...originally exhaust was first, but then Stillen had a sale and I snatched the G3 intake

As for aftermarket adjustables...is that something someone who doesn't know a whole lot about it can do? I mean, I've got adjustable progressive shocks on my bike, but I turn that up/down depending on if I'm riding alone or not.

I figure with a car it'd be more complex (to a 4th!)

Also, how difficult would it be to DIY a coilover swap? I imagine the (rear) springs aren't going to be easy. I know when I swapped shocks on my truck, I cheated and used my car jack to compress them to where they'd bolt up. With the Z being as low as it is, I figure that won't be very likely.

RCZ

Hmm... first off, When you are ready...I can get you a pretty good price on the KW's.

Second..you may not really need to go so crazy as getting coilovers, check out some of the available options for lowering springs. Otherwise, they arent complicated to play around with. They give you parameters to stay between, however if I were you I would just use the settings they put on the V3's from the factory, they are perfect.

Don't forget also that you will NEED camber adjustable control arms so you can add another bunch of money to your estimate.

As far as how hard everything is to install... Its pretty straight forward, but if you do it in your garage it will take you a good amount of time...specially if you are doing the control arms too.

ChrisSlicks

Sway bars did wonders on the bumps for me. Allows much less bound and so the re-bound doesn't kick the rear out.