Rear bang over bumps/railroad tracks

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Rear bang over bumps/railroad tracks

Postby CaptainSquirts » Tue Apr 24, 2018 2:00 pm

Slaloms felt the same, so thats good since I liked how it felt already. Last event on the turn around I was getting some inner wheel jerking or something when it planted after lifting. This event, it didn't do that so thats good also.

The main issue though I still get oscillation when going over some uneven surfaces/railroad tracks. It doesn't happen at low speeds. Only when going over 35ish + it'll happen. I contacted the coilover company and spoke to their suspension expert. Informed all the different things I've tried and tldr, they're going to send me a new shock body. Interesting thing they noticed when the coilovers were rebuilt, they marked them as Fortune auto 500 instead of the 510 version that I have. So not sure if that had to do with how it's acting but w/e. They think it probably has to do with shim installation error. They "dyno test" after the rebuild but they said it'll show positive if its a shim issue so it'll be valved for a lower # rather than what my spring is.

At this point since they'll send me a new shock body(if things go as planned) then I'm happy with that outcome rather than sending in my coilover and then my DD being out of commission until I get them back.
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Rear bang over bumps/railroad tracks

Postby Loren » Tue Apr 24, 2018 4:17 pm

Wow, sounds like a legit suspension outfit. :notworthy:
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Rear bang over bumps/railroad tracks

Postby CaptainSquirts » Fri Aug 30, 2019 1:03 pm

So this issue I've been having since I've installed the coilovers is now gone.

tl;dr of the problem I had was when going over some certain bumps like train tracks, pretty much anything that has a big quick up and down would cause my rear to pogo pretty badly.

So in a thread on the Evo forums someone mentioned when installing new coilovers the rear was very bumpy, jumpy, kinda like my situation. Someone mentioned that when torquing the arms that the coilover attaches to, the manual says to have the ride height when tightening that to be at the static ride height. So when I installed my coilovers, I had the car on jackstands and hanging down to maximum droop. At static ride height, the arms are parallel when I installed and bolted on the coilovers, the arms were more angled down, like a good 20 degrees. So I untightened the nut/bolt holding the bottom of the coilover, jacked the arms up to be parallel and then tightened everything back down.

I now no longer get the pogo oscillating affect on roads/tracks I would normally get it on. I'm super pleased with the outcome. The real test will be lakeland, my rear was super bouncy at the last event.
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Rear bang over bumps/railroad tracks

Postby Loren » Fri Aug 30, 2019 2:29 pm

Yeah, that's pretty standard procedure. You don't want the bushings to be all bound up at static ride height.

Never thought about it causing that particular problem. But, it makes sense.
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Rear bang over bumps/railroad tracks

Postby Native » Fri Aug 30, 2019 2:58 pm

CaptainSquirts wrote:The real test will be lakeland,
We'll need a car for the test run in the morning... :grin:
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Rear bang over bumps/railroad tracks

Postby twistedwankel » Fri Aug 30, 2019 3:53 pm

Daniel Dejon
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Rear bang over bumps/railroad tracks

Postby CaptainSquirts » Sat Aug 31, 2019 3:04 pm

Loren wrote:Yeah, that's pretty standard procedure. You don't want the bushings to be all bound up at static ride height.

Never thought about it causing that particular problem. But, it makes sense.
Yea its crazy it made THAT big of a difference.
Native wrote:
CaptainSquirts wrote:The real test will be lakeland,
We'll need a car for the test run in the morning... :grin:
XD
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I would pay to see you do that.
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Rear bang over bumps/railroad tracks

Postby lddavis91 » Mon Sep 02, 2019 1:29 pm

CaptainSquirts wrote:
twistedwankel wrote:https://www.bing.com/videos/search?q=po ... &FORM=VIRE

I think I've found my calling.
I would pay to see you do that.
:lol: I've got $20 to contribute to that cause.
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Rear bang over bumps/railroad tracks

Postby twistedwankel » Mon Sep 02, 2019 3:10 pm

Not to worry as I have met deductible for medical insurance all ready this year :wise: Let the games begin. I did over 1100 continuous hops on one as a kid just because. Hey we didn't even have hula hoops or frisbies yet and had party lines so you had to wait your turn with a dial phone several others could listen in on. Had 2 BW tv channels mostly live that shut down every nite at 12am and showed a test pattern. But I digress. Still learning facets of my first Smart phone out of necessity. Better no. Quicker Yes.

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