Harsh Ride In R32 Gtst

[B0oStEr]

I've fitted some koni yellows and kings springs to my r32gtst.

Due to the konis being modified gtr ones the available adjustment of the platform height can only just capture the spring with little or no preload.

The car is also too low (310mm guard to wheel centre) and the ride is noticeably "jiggly".

I'm having new higher circlip grooves cut for the spring platform on all the shocks to raise the ride height.

The top groove should raise the ride height about 37mm and give the springs about 40mm of preload.

Will the ride be affected noticeably (firmer?) by the increase in preload?

The stockies seem to have about 40mm but is 40mm too much preload for the kings springs?

[Nebuchernezzer]

Increasing preload will make your ride firmer, it will also reduce your travel since there is less distance for the spring to travel before it reaches crush height.

No idea if 40mm is to much preload.

[blind_elk]

The spring only supports the weight of the car. So pre-loaded or not, the ride should be unaffected.

The "jiggliness" of the ride is possibly due to the valving of the Konis - they control the oscillations of the springs when the car travels over irregularities in the road surface.

You may also be reaching the limt of "bump" travel of the Koni, resulting in your car hitting the bump-stops - that certainly gives a rough ride.

[Sydneykid]

I've just fitted some koni yellows and kings springs to my r32gtst.

Due to konis being modified gtr ones the available adjustment of the platform height can only just capture the spring with little or no preload.

The car is also too low and the ride is noticeably "jiggly".

I've had new higher circlip grooves cut for the spring platform on all the shocks to raise the ride height.

The top groove should raise the ride height about 37mm and give the springs about 40mm of preload.

Will the ride be affected noticeably (firmer?) by the increase in preload?

The stockies seem to have about 40mm but is 40mm too much preload for the kings springs?

<{POST_SNAPBACK}>

What is the height, centre of wheel to guard on all 4 corners? That will enable me to tell you how much travel you have. The Skyline Konis are very firm, but it is mostly bump stop contact that I find causing harsh ride.

If it is lower than 350 mm front 340 mm rear then it is most likely bump stop contact. You may need to raise it and trim the bump stops, the height will tell the answer.

cheers

[B0oStEr]

I've refitted the konis/kings using the newly cut +37mm top circlip grooves.

The guard to wheel centre height is now 345+/-5mm all round.

It was 310mm so riding close to the bumpstops.

Ride is a bit better now but still feels a bit jiggly.

Are the gtr koni sports stiffer than the ones for the gtst?

Mine are 8041 1147, 8041 1148 but I've been told they should be 8041 1336, 8041 1337

The kings springs are rated at 175 lb/in front and 155lb/in rear which is not that much stiffer than stock yet it feels much stiffer.

I have the shocks set at their softest setting but it feels as though springs and shocks are not working together properly.

I'll try setting the shocks firmer but it seems to me that this might only make the mismatch worse.

[Sydneykid]

I've refitted the konis/kings using the newly cut +37mm top circlip grooves.

  The guard to wheel centre height is now 345+/-5mm all round.

  It was 310mm so riding close to the bumpstops.

Ride is a bit better now but still feels a bit jiggly.

Are the gtr koni sports stiffer than the ones for the gtst?

Mine are 8041 1147, 8041 1148 but I've been told they should be 8041 1336, 8041 1337

  The kings springs are rated at 175 lb/in front and 155lb/in rear which is not that much stiffer than stock yet it feels much stiffer.

I have the shocks set at their softest setting but it feels as though springs and shocks are not working together properly.

  I'll try setting the shocks firmer but it seems to me that this might only make the mismatch worse.

<{POST_SNAPBACK}>

Give Marco a call at Top Performance (the Vic Koni agents) and talk to him about Skylines and Konis.

cheers

[B0oStEr]

Thanks SK

Marco cleared up a few things about my konis.

Before koni released the specific models for the rwd skylines Top Performance adapted the gtr ones to suit.

The valving remained unchanged.

Apparently the new gts specific ones still use the same valving but they now consider the rear ones too stiff and when they import new stock they will be a softer spec.

They have revalved some already and it's supposed to improve the ride and handling noticeably.

Has anyone here had them revalved?

Is it worth the $220?

[GTR32]

I've worked with Marco to come up with settings for a daily driver R32 GTR - at least on the rear so far. They are excellent and he is a champion, you won't be disappointed.

[B0oStEr]

I've put up with these rock hard shocks for 18 months because I rarely drive the car.

I never got around to having them revalved because I'm not sure the result would be what I'm after.

I have a few unanswered questions about these Koni yellow shocks.

I bought them second hand with Kings springs KDFL101 and KDRL102.

Apparently they were gtr shocks modified by Top Performance to suit the R32gtst before the specific model Koni for the gtst was made.

Using the top spring-seat circlips and the Kings spings the ride height was 310mm and the ride is rock hard.

As I said in an earlier post I had new grooves added to raise the ride height and it now rides at 345mm.

Why was the ride height so low?

Thinking about this the kings springs are only a bit firmer than stock (175in/lb front, 155 in/lb rear) so the bump and rebound rates for the konis must be responsible for the hard ride and would be much too firm for the king springs.

If they are designed for harder springs that compress less then the intended ride height would then be higher than 310mm.

Marco from Top Performance said they have revalved some of the rear shocks but the fronts were considered ok as is.

I think my fronts are too hard and would need revalving as well.

Obviously, if the ride height was low because they were designed for harder springs than the kings then they would need to be revalved to suit the kings.

Can anyone running koni yellows tell me what springs/rates you are running and how compliant your ride is?

Better still if someone has had their's revalved and can tell me the difference then that would be great.

Thanks

[B0oStEr]

I spoke to Marco from Top Performance again this afternoon.

He confirmed that the original konis for the gtr and hence these gtst shocks were built using valve rates specified by koni in japan and are probably designed to work with springs much stiffer than kings gtst springs.

Top Performance can revalve them for me to their own spec for $130 a corner but I'm considering selling these to someone who needs the higher bump/damping rates and putting the money into a set of SKs bilstiens.