civexspeedy

I recently received and installed the Koni/GC coilover setup, ordered direct from GC and came assembled and ready to install. I ordered spring rates of 650#/550#, all in 6" free length springs. After installing, I dropped the car and quickly noticed the car was still at around the stock height. Raised the car up, lowered the front coilovers to their lowest possible setting and the rear just a bit. Dropped the car and noticed very little change. The car dropped MAYBE 1/2" from stock suspension height all around. BUT, looking at the suspension, the front coilovers are literally resting on the bump stops. They are sitting on the bump stops, with no more room to lower, ZERO suspension travel allowed and the car still looks like it's at stock height.

The rear is a little better, but not by much. As the car sits, I have about 1" of travel before hitting the bump stops. BUT, the car is still at around stock height. If I lower the car any more, which I would want to, then the rear will now be resting on the bump stops. No travel, still not very low.

I've contacted Ground Control. Sent them pictures. Explained everything. The person I spoke to said the part numbers are correct, everything looks installed correctly. His suggestion was to put the SOFTER springs up front and to cut the bump stops. He thinks this could solve the travel issue and lower the car. Putting softer springs up front will not solve anything. Cutting the bump stops still will not solve anything either, because ideally I would still want to lower the car at least an inch. If I cut the bump stop and lower the car, I'll still be left with VERY little shock travel or be resting on the bump stops again.

I show this all to my friends. All of which have countless of years dealing with aftermarket suspension, racing, some are automotive engineers who design aftermarket parts. We all come to the same conclusion. Something is not right in the design of this coilover as it is. I am waiting to get a call back from the Ground Control owner or whoever is in charge of designing this setup to get their input. Their website has listed that this suspension should get me 0"-3" of drop, that is CLEARLY not the case. Even if I were to remove the bump stops entirely, I don't think I'd get closer to a usable 3" drop.

Curious to hear what anyone here has to say about this. The main issue that I see, and what all of my friends see, is the Koni body seems to be far too big, with very little shaft to make for no travel when used with these coilovers. This should have been apparent when GC designed this setup, but may not? Thoughts?

bigtimegambler

So either the springs need to be taller ( 8" springs) or the shock bodies need to be shorter. The bump stops need to be trimmed from what I can see, probably about a third.

Did you roll the car back and forth at all? when you first lower the vehicle down the suspension is not settled.

Even with the bump stops cut you don't have near enough shock travel. I think the real issue lies with the 6" springs.

My EF has 8" 550# front/rear and I have no problem going low. By having those 6" springs the shock has to compress further to rest on spring.

Garage_Spec

Changing the spring height won't get you anywhere. The shocks are just too long. I'm sure it's the correct part but yellows aren't really meant to be lowered much more than stock. A shorter shock will bring the height down and cutting the bumpstops in half would be fine. That's my opinion based on messing with numerous Koni sports myself. It just seems that the spring seats are really high and the cartridge end would have to go lower to compensate for the lower ride height.

brixcivic

get 8" springs and extended top hats.. should solve your problems

F22Master

Those bumpstops are a mile long! Cut those things at least in half. Then look into some extended top hats. I would also see if you can exchange those 6" springs for 8". That should get you close to 2" lower than stock.

BUT, i do see your point that the shock bodies are much too long. Not sure what you could do about that.

Garage_Spec

Longer springs will only keep him from being able to lower the car as much. He is already having issues with it being too high. Just needs a shorter shock shaft and body. I would call Koni and see what they could do for you.

CW-ITR

iTrader: (11)

^ I totally agree to the above.

For those of you who suggested longer springs and adding top hats, don't you even read the OP's post? Seriously, if you want to help, do spend some time and read the problem first. For crying out lound, look at the wheel gaps Sorry, I know I'm in a bad mood. But, I know I'm right.

CW-ITR

iTrader: (11)

OP, why don't you ask NSX guys on NSX forum to see who runs Koni to take pics and measurement of their shocks. Those shocks look awfully long.
Another thing I can think of is your car is on an extreme diet that a regular off the shelf NSX Koni spec shocks couldn't keep up with. LOL!

dirty19

iTrader: (1)

The sport dampers are not shortened like the SPSS3 race valved dampers.
I'm thinking the only alternative now is to transform the sports into SPSS3's
That would give you more room for lowering.
I also wouldn't cut any bump stops.... One sure fire way to start slapping metal imo.
Kind of doubt GC would take them back since they have been installed already. Look at what it would cost to transform what you have now into the spss's
Call GC back and discuss options.

Atomic1

Why would you not consider the extended top hats? They should be compatible with that drop range, and they will move the bumpstop upward. Using a shorter shock shaft will gain room too, but its going to be really expensive.

dirty19

iTrader: (1)

agreed on the above but if he can afford an nsx the cost of proper dampers should not be an issue ?

civexspeedy

Posted on NSXPrime and have received some feedback with photos. One person did mention an issue(different than mine) with their setup and having to deal with GC numerous times to get the problem solved. His front shocks are noticeably different than mine. Sources are scarce for this specific setup on an NSX..

AFAIK, no SPSS3's for this car. Waiting to speak with the owner of GC to find a solution. The person I spoke to at GC wasn't any help. He suggested swapping the softer springs up front and cutting down the bump stops. Also seemed surprised when I told him their website states a 0-3" drop and this is clearly not the case. Even another user said once he got his Koni/GC setup to work, it can only drop about 2-2.25" at most. Which is enough, but not what's advertised at all.

This isn't a civic, no extended top hats. There is no room under the hood and rear hatch for an extended top mount.

I have 2 other dedicated autox cars and a daily driver and added the nsx just about a month ago. Maintaining and building 4 cars, 3 of them used for fun/racing is expensive and time consuming. Since the NSX is not classed competitively for autox, I have no desire to go all out on it. If I did, I'd more than likely go with KW(over 2x the cost of this). This will be a mild ST* build and fun car to see what I can get out of it. Seasons over for me, I have 5 months to make it work. If I can make it work well, great. If I can get a good solution, I'll move on to something else. But for this car, it's either cheap Megan, BC, Tein or more expensive KW, Moton, MCS, etc. This is a good middle ground and obviously very popular in the autox community. Worth a shot for me to try and make it work.

CW-ITR

iTrader: (11)

Good luck on working with GC getting the problem solve. With their false advertising, they should go beyond their means to accommodate you.

dirty19

iTrader: (1)

Id have to agree with this 110%.
No way can they advertise a 3 in drop sell you a not so cheap set of dampers and have no support or fix for this.
I'm surprised they have nothing in the spss3 for this car.

F22Master

Im not sure how anyone is pinning this on GC. The GC products (sleeve and spring) are just fine. All of the problem with this setup is in the Koni shock. I know you ordered the setup from GC, but all they did is order the shock that Koni specs for your car. The main issue is Koni got the specs wrong for the car. I would talk to Koni before bothering GC any more.

civexspeedy

Ground control products on their own are just fine, same with Koni. Koni has no fault in this as they simply design the shocks, more than likely with the intention of using with stock springs as the Sports for most cars are built around the OEM spec sizes. Where GC *is* at fault is that they are using their product to work along side some other product that may not have had an intention of being used the way GC is intending. GC then has the responsibility to produce and sell a kit that works as advertised. If it doesn't, it's on GC because GC is the one selling this, Koni is unknowing and has no connection with the kit itself, it's all GC.

But, I finally talked to the owner, Jay for a good bit. He's overnighting new, shorter, progressive but stiffer bump stops to use. He's owning up to saying it seems like it was a mistake on their part to send the bump stops that came with the setup. Hoping I can swap them out before the weekend and see how things pan out. Hope this will solve any issues and I can enjoy beating on this suspension for years to come. I still don't see 3" usable drop as advertised ("This kit fits the 1990-1997 Honda Acura NSX. This kit will allow you to lower your vehicles ride height up to 3” without the worry of constantly bottoming out"), but if it works the way I need it to, I'll be fine with it.

Jackson

This may be a dumb question and you'll have excuse me because I've never touched an NSX suspension but just about everything else. Is it possible to mix up the front and rear shocks and top hats when installing? It looks like the longer shock up front is the one you're having issues with and the other shock looks very similar but is a bit shorter.

civexspeedy

The front shocks mounting point to the hub is thinner than the rear. So since the rear shock mounting point is thicker, it wouldn't be possible to fit it on the front hub assembly. Quickly noticed the difference when I was installing the suspension.

90_EX_Civic

just going to throw this out, did you clock all your bushings correctly? binding somewhere? sway bars holding it up? but like everyone else has said, those koni's do look really tall, especially for a 6" spring.