Koni suspension --- Part 3

[McCoy]

Well, I might as well start up a new thread for this round of suspension upgrades.

The new hotness for 2008... 8611's up front and 8610's in the rear to work with Z32 uprights. Spring rates will stay the same, 550F/400R, but might change depending how the first few track days go.

http://www.sr20forum.com/gallery/data/959/medium/Koni_front_and_rear.jpg

A new knob to play with...
http://www.sr20forum.com/gallery/data/959/medium/koni_8611_bottom.jpg

I did have to run down to the local machinist today to have them enlarge the I.D. of the tophat from 20mm to 24mm due to the girth of the 86XX shaft.
http://www.sr20forum.com/gallery/data/959/medium/GC_tophats_enlarged.jpg

I resorted to using a pickle fork and a 5lb sledge to get the S13 rear upright off tonight...
http://www.sr20forum.com/gallery/data/959/medium/S13_rear_upright_removed.jpg

And a comparison of the Z32 uprights (top) to the S13 uprights (bottom)... I'm still shocked now light the Z32's are :). I still need to knock out the seal on the Z32 upright, I soaked it PB blaster and will knock or cut it out tomorrow morning.
http://www.sr20forum.com/gallery/data/959/medium/Z32_and_S13_rear_upright_comparo.jpg

[Def]

The shaft diameter of the 8611's is 22mm BTW.


I need to get on my install!

[Epstein]

That seal on the Z32 upright will just tap out with a hammer and screwdriver.

Are people having a hard time getting these uprights? I've got a spare set in my garage.

[Def]

Epstein - I actually need another set for some development work. I'll shoot you a PM.


A local junkyard wants $65/ea for Q45 rear uprights(same as Z32). Makes them stupid expensive for pulling them yourself even on the 50% off day(Wednesday). If they were more reasonable I'd take a half day off on Wednesday and get to pulling me some uprights.

[McCoy]

That seal on the Z32 upright will just tap out with a hammer and screwdriver.

Are people having a hard time getting these uprights? I've got a spare set in my garage.
That's what I was trying last night, but it wasn't going. It should go this morning after soaking all night.

I got my uprights off Zilvia for $70 shipped IIR.

[McCoy]

OK, the seals came right out this morning... it did help to flip the uprights over, it seems they only want to come out one way ;).

[McCoy]

Finally got the drivers rear buttoned up. For as many nissan nuts/bolts that I have laying around the garage I didn't have anything in the right length to work with the Z32 lower mount... so I bought some grade 8 bolts at the hardware store today.

http://www.sr20forum.com/gallery/data/959/medium/Koni_8610_rear_installed.jpg

I noticed that I lost some droop, not sure how that will affect things, if at all. Left is with the 8610, Right is the Koni Yellow.
http://www.sr20forum.com/gallery/data/959/medium/koni_droop_left_8610.jpg

[Def]

Given that your springs aren't compressed at all at full droop on either, I don't think it matters. Your shocks aren't going to let the wheels go below where the spring pushes them in real usage.

I've thought about going with a tender spring setup in the rear to get a little more actual droop travel that might help things be "smoother" out back on big bumps.

[raen419]

The 8610 shocks you've installed are shorter than the standard Sports aren't they? If so, that could be it.

[McCoy]

Def - Yeah, after thinking about it some more I'm not that worried. I'm pretty sure they have as much droop as the Silkroads that I took off last fall. I will probably have to go to a 8" spring in the back though. Currently I have a 400lb 7" spring and I have the perch adjusted all the way to the top... and I'm still about 1" lower than I want to be back there. Luckily, I have a 440lb 8" eibachs in the garage that I can swap to.

Raen419 - Overall the 8610 setup is shorter, I'll post a picture later if I remember to snap a shot.

[SoSideways]

Yes, please post pics of your car on the ground with your current 8610 setup in the rear, because I'd like to see what kind of ride height you're at.

Then again, I can always measure my entire coilover's length to give Veilside180sx an idea of how long of a housing to make :)

[McCoy]

A quick comparison of the Koni yellow -vs- Richards housings (S13 with Z32 uprights) with an 86XX insert.
http://www.sr20forum.com/gallery/data/959/medium/koni_8610_yellow_comparison.jpg

I cranked the perch up until the spring was tight against the pillow mount.
http://www.sr20forum.com/gallery/data/959/medium/koni_8610_rear_ride_height_adjustment.jpg

And this is the max ride your going to get, in the back, with the 8610-1436 insert and the housings that I have. The rear is about 1/2 to 1" lower than I wanted. I guess I can add a 10mm spacer up front and drop the front down to get the car level again... or just not worry about it for a while and see how it goes.
http://www.sr20forum.com/gallery/data/959/medium/koni_8610_rear_ride_height.jpg

[veilside180sx]

Funny thing, is that ride height is about an inch higher than most other people want.=)

[Epstein]

That's too low? Are you trying to run a stock 27.x" fender height?

I know a certain S13 with Z32 rears that that could use that setup at that height.... if you need a quick out to get something taller. :)

[McCoy]

Chris, I need the height to clear the 275 RA-1's mostly. Also, I live in a very hilly area and I need the extra ground clearance to keep the nose and muffler from dragging all the time :).

I'm thinking this setup will work ;)

[McCoy]

First test drive in, feels good... I haven't played with the dampening at all from what I started with, but overall the car feels better on the rougher sections of road and can soak up the biggest of railroad tracks easily :).

The 8611's up front are set to 1.5 turns on the rebound and 0 turns on compression... need to turn those up to 1 turn, but forgot.

The 8610's in the rear are set to .75 turns on rebound

[Def]

haha - I expected to see a car in the weeds with all this talk of limited height. I think my car is pretty high and it's probably 0.75-1" lower than that.

Drop it down - it handles better. Bumper scraping is just a part of life. :)

[turtl631]

Wow, yea, that is pretty high. My stance coilovers with Z32 mounts let me run a max height that's probably 1.5" lower than that. I think if you raised it much you'd be at stock height...although the big 275/40 sidewalls could be making it look higher than it is, too.

[McCoy]

although the big 275/40 sidewalls could be making it look higher than it is, too.
Those are my street tires on there currently, 235/45/17 Advans on 17x9's.

Def - If I go any lower up front then I need 10mm spacers to clear the perch to tire and 20mm fenders, for now I'll run it at this height and go down when I feel like spending money on fenders and paint.

Here is my clearance with the 275 RA-1's... after I pulled the front fenders, imagine 10mm spacers being added to this setup now. I guess I can always try and pull the fenders some more, but not sure how much more I can get out of it.

Inboard clearance at current height.
http://www.sr20forum.com/gallery/data/959/medium/RA1_test_fitment_no_spacer_02.jpg

fender clearance after pulling as much as I could.
http://www.sr20forum.com/gallery/data/959/medium/Eastwood_front_03.jpg

[turtl631]

How close is it under compression? Looks like it clears fine now, but I could see how having it 10mm further out could be an issue.

[McCoy]

1-2mm under compression... I'm going to add some 2-3mm spacers up front to make sure there is enough room for play on track.

[Epstein]

Can we get a detailed comparison of ride quality between your various setups? Please include spring rate info. I'm itching to buy your same setup but with about 100# less spring. I just want to hear about street manners.

[Def]

What rate and length spring is that up front?

I'm wondering if these 5" 420 lb/in(7.5 kg/mm) springs I've got would even have a chance at working. I'm thinking they'll coilbind too easily. Just trying to get a feel for where on the collar the perch with a given length spring and rideheight.

[McCoy]

Chris,

I've only had the 240 for a year, and have only had 2 other setups to compare this to.

The car came with Koni Yellows and stock springs which I drove for about 2 months before switching to the Silkroads. The car road ok with this setup, but the springs were to soft and not matched to the koni yellows to well... needed some stiffer springs.

I switched to the Silkroad RM-A8 coilovers before the first track day last year and got a good 8 track days in and a years worth of driving on them. The spring rates were 6K/5K (330lb/300lb), these were dropped from the original 8K/6K by the original owner because the car felt to stiff to him. I found the suspension felt good on track, no real complaints there. On the street was a different story, any expansion break or patched section of road felt like a wheel was about to break... way to much compression. There was no real good setting for the dampers to make a day drive enjoyable. Railroad tracks were taboo and any rough concrete roads made your teeth chatter. I guess this is typical of most JDM coilovers under $1500. I enjoyed my AGX/GC setup on my sentra a heck of alot better than these... and I was at alot higher spring rates on the sentra too.

With the Koni's I'm now running 550lb/400lb rates and I've made no other real changes to the car. here is a writeup I did right after installing the 8610's up front last Novemember and from my 10 minute drive last night is not much different. I still need some more seat time and to find some more of my normal roads to drive as the weather gets better.


More driving impressions:
I was able to take the car out for a drive on Saturday to get a better feel for the front suspension. I took a normal road that I normally take each day to work, the road is patched in a few spots and has a railroad crossing with uneven pavement on both sides. I usually have to slow to 15mph when crossing the railroad tracks with the 240, if not it just feels like your going to break something on the car . I hit the tracks at about 30mph and it just felt amazing, just a thud thud thud, the car went up and down with the road, but the normal jolt I was used to feeling wasn't there. And to think I went up 200+ lb's on my spring rates too . As for driving ove the patched sections of road or just rougher sections... you can feel it, just not as bad as the typical JDM coilover. The roughest of roads is still not as comfortable as say the outback, but that's not what I was after with this setup to begin with .

[McCoy]

Def - these are 550lb, 6" springs up front. If I decide to go up in spring rates, then I'll probably go to a 600lb, 5" spring... with the springs being that stiff, I'm sure coil bind will not be an issue and I'll be able to drop the front a good 1 inch.

I would be concerned with the 420lb, 5" springs though...

[Your Mom]

get those yellows ready to ship!

I really want to get out and drive mine. one more week of wiring and it'll be on the road.

I got another 240 that has the KTS coilovers on it. There ok. very bouncy. more than richards car which isn't too bouncy just felt light on its feet. but i'd take these kts over my old D2's. so i can't wait to see how the koni/gc's feel.

[McCoy]

Brian, don't remind me of the D2's, those things were scary to say the least :eek:

I'll ship them out tomorrow... the good part about Portland being a major hub is that Fedex ground is only 1 day between me and Richard :)

[vw_nissan]

Def - these are 550lb, 6" springs up front. If I decide to go up in spring rates, then I'll probably go to a 600lb, 5" spring... with the springs being that stiff, I'm sure coil bind will not be an issue and I'll be able to drop the front a good 1 inch.

I would be concerned with the 420lb, 5" springs though...


So would you say 7" springs should be better if you are running in the 450-500lbs range? I talked to Rich about it, and he suggested 7" all the way around, and I am thinking about running about 500lbs front (with 8611) and about 400lbs (with yellows) at the back.

Did you by any chance measure how long the JDM springs are?

[veilside180sx]

So would you say 7" springs should be better if you are running in the 450-500lbs range? I talked to Rich about it, and he suggested 7" all the way around, and I am thinking about running about 500lbs front (with 8611) and about 400lbs (with yellows) at the back.

Did you by any chance measure how long the JDM springs are?

7" spring helps with the "lighter" springs for distance to coil bind, but 5" helps with tire clearance. Really it's going to come down to which you think is more important.

[Def]

Yea, keep in mind that going up in rate for the same length spring doesn't net you as much total force to coilbind as you'd think. While the spring is resisting compression, it also has less distance to go before coilbind due to the thicker spring itself. So as rate goes up, compression distance of spring to coilbind goes down. The net effect is that it increases total coilbind force some, bu not a huge amount.

That said, at a little over 1200 lbs to coilbind, I bet a good bump will slam these 5" 420's together. I'm going to toss them on and see.

Another thing that looks like will happen with the 5" spring(regardless of rate) is that you'll be so high up on the collar that you could be talking about coilbinding before you fully compress the bump stop.

[McCoy]

I'm pretty sure in the long run... maybe next year or in two years I'll eventually go to a Silvia front and add go with wider fenders. This way I can use a 10mm spacer and run a longer 8" spring up front without worries.

[vw_nissan]

ic....with the skinny tire size that i am running, tire clearance won't be an issue. :p

[McCoy]

I drove the car yesterday with compression turned up to 4 clicks... alittle stiffer that I wanted for daily driving, so I turned it back 2 clicks and seems to feel better.

I'll know alot more next week when I finally get the car on the track. To bad I won't be able to use the RA-1's... no hitch yet for the 240 and those tires just don't fit behind the seat like they use to in the sentra ;).

[SoSideways]

If you had a hatch you would have been able to fit 4 wheels in there no problem :)

Can't wait for your review Mr. McCoy :D

[a_ahmed]

^unless you have a cage hehe...

I feel with my stripped hatch i can have a camp fire and bbq in the back lol, lots of space.

[SoSideways]

^unless you have a cage hehe...

I feel with my stripped hatch i can have a camp fire and bbq in the back lol, lots of space.

You're not kidding.

Back in 2005 when we had those series of hurricanes barreling down Florida, I ended up packing up all the valuables in my apartment into my car, and luckily, it was gutted on the interior, with just the 2 front seats being the limiting factor in what I can/cannot put into the car.

I ended up packing my 20" tube TV in there, my computer, monitor + accessories, my school related stuff, personal valuables, some clothes, etc. In short, my entire apartment fit into my car.

Oh, and it wasn't a bachelor's apartment either, I was living with my girlfriend at the time, whom is now my wife, but we both just shoved everything in the car and drove.

In 2006, I was able to put all 4 225/45/17 Kumho MX plus the 4 17x9 +20 FN01R-Cs in my car to take them down to the shop to get the tires mounted :)

I <3 my hatch.

[McCoy]

I miss my NX2000 for this reason. I removed the back seat and carpeted it, and for autocrosses I was able to stuff a full set of wheels between the front seats and the rear STB, A 10x10 canopy, HF aluminum jack, big tote with all the tools and misc stuff, helmet, and everything else needed for a weekend of fun. The best part was that I could still see out the back window :)

[SoSideways]

This is a pic of when I had the rims and tires both in the car, when I took them down to get the tires mounted.

http://i42.photobucket.com/albums/e346/SoSideways/eat_your_hearts_out.jpg

I left the front seat free there.

[Def]

I stuck an 8' long ladder in my S13 hatch when I was in a more home improvement mode. JDM turbo utility wagon!

[SoSideways]

I'm seriously tempted to buy an S13 hatch shell and turn it into a K-Style 180sx pickup. Would be perfect as a support vehicle hahaha

[McCoy]

Just to update... I've been daily driving the car for the past couple of months now, and the outside temps are just starting to get into the 70's to 80's over the past few days. The ride seems to be a heck of alot better now that the temps are higher... I didn't think it would be this much of a difference, but it is. The really rough roads are a bit more bearable and breaks in the road and the railroad tracks feel alot better now too.

Still enjoying the suspension... :)