so I'm posting this here because it's a track only car.

the rear end of my recently acquired EG trackcar feels extremely bouncy. It has Mugen NZ dampers (several years old), with 500 front and 600 rear springs.

I've never had a honda (let alone a stripped out hatch) before, so I don't know whether I should just expect a bouncy rear end (I know how that sounds, lol).

seriously, when I roll over a speedbump, the front sort of absorbs the bump, but the rear launches up and then oscilates once or twice (1/2 an inch up and down maybe) before being still again. If I put the tailgate down and shove down on it, the car will move up and down maybe 2-2.5 times (so down, up, back down and a slight quiver before being still).

The dampers look just fine. there are no leaks or evidence of fluid having run out. however the little screw that supposedly controls the damping seems to have little effect at all on how bouncy the car is. Full stiff and full soft feel pretty much the same.

I am wondering:could it b that the rear of the car is just so light that it is going to be bouncy no matter what, or do I really just have blown dampers?

I 'd hate to have to get my dampers rebuilt, since I don't think they even rebuild them here in the US. I wonder if there's a cheaper alternative that might be just as good as rebuilding..

anyway, sorry so long winded, just trying to figure out this car.

I've had it on the track like this, and it does just fine (track's not very bumpy), but driving to and from the track is really frustrating when my tools, wheels, jack and whatnot shoot up in the air and crash down every time I go over a bridge joint...

any thoughts?

 

Could be:

1) Shock is does not have enough dampening for that amount of spring rate.
2) Yeah with 600lbs springs it's going to be bouncy. I remember putting 400lbs springs in my 00 Civic Si on the rear and it was bouncy.
3) or something ruptured inside the shock housing.

 

my eg road/race car is pretty light under 2000lbs and I have run 600lbs in the back and its okay a little bouncy but nothing to make my tools etc.. bounce around.

 

It sounds like over sprung, or the rear shocks are blown.

 

from everything i have seen, the mugen dampers have a very linear curve. This makes for the bump absorption to be lacking.

600lbs rear springs is really nothing, i run some were in the neighborhood of twice that.

 

ok thanks.

I'll just keep them set to full stiff for now until I can arrange for a rebuild.

maybe I'll try to source some rear shocks/springs temporarily...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by L8APX &raquo;</TD></TR><TR><TD CLASS="quote">I'll just keep them set to full stiff for now until I can arrange for a rebuild.</TD></TR></TABLE>

They need help, but this is the most you can do for now.

I'm 600 on the rear, and it's stiff, no rear booty jig-lidge on bumps

 

So I took the car down to the local Honda dealer/parts folks, and they pushed, pulled, jumped on, wiggled, shoved and bounced up and down on the car, and they say the dampers are just fine. They had the koni/GC's in stock but told me I really didn't need them. they said a blown shock is very obvious, and i didn't have one

on the ride home I could swear that the rear of the car flies up off the gound after going through a dip, while the front just kind of absorbs it.

Not sure what to think. I guess I'll put heavy blankets under my jack and stuff so that they land on the blanket after flying up after bumps. sometimes they do it twice even; "BANG--bang" as the rear of the car digests the bump.

I almost want to buy the rear shocks/springs just to see if they make a difference. they're only $282 for both rears.


Modified by L8APX at 2:33 PM 4/19/2008

 

I should maybe add that the car has a full cage, so the shell is very stiff too.

 

Blown is not the same as worn-out. Just because fluid is not leaking does not mean shocks are not due for a rebuild. How many miles are on them, and how many are street miles?

King Motorsports can arrange for a rebuild of those coilovers.

The car shold not bounce after the suspension has been compressed. Shocks control the spring movement...and if the shocks are worn the springs will continue to oscillate if met with little resistance.

 

I found the problem: one "damper" does NO damping. the other 3 compensate for it a little, but it is shot.

I ordered some threaded sleeves and lower perches form Koni today, and an aquaintance will hopefully be selling me his gently used koni shocks (EG front; ITR rear).

I hope to disassemble my coilovers and re-use the springs and tops with the Konis while the Mugens are getting rebuilt.

Hopefully this will solve my bouncing issue.

 

just replaced the rear dampers. 1000000000% improvement. it's a whole new car. no bouncing at all.

the guy at Gillman Honda is an idiot.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Todd00 &raquo;</TD></TR><TR><TD CLASS="quote">Blown is not the same as worn-out. Just because fluid is not leaking does not mean shocks are not due for a rebuild. </TD></TR></TABLE>

Bingo. Shock oil, like any oil, will break down over time.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by L8APX &raquo;</TD></TR><TR><TD CLASS="quote">just replaced the rear dampers. 1000000000% improvement. it's a whole new car. no bouncing at all.

the guy at Gillman Honda is an idiot.

</TD></TR></TABLE>


Good to hear. BTW your spring rates are a little on the low side. Nothing significant but could be depending on what tyres and brake specs you are using.

 

who here loves fat b.tches?