concealer404

iTrader: (3)

I personally like the 550/350 rates. I've never regretted adding more spring to a Miata. Off the shelf Bilsteins work well with the 550/350 rates.

sHOT1980

Thanks all.
Order placed, finally went for 450\350 7" springs. Will try this setup in May.
I'm a bit afraid of 550 - but maybe I was totally wrong.
Best regards to all. It's very helpful tread!

icepenguin66

I used to have a SM back in the day but been about 8 years and I'm so freaking out of the Miata performance loop now. Damn my head hurts after reading multiple threads over and over the past week. I'm still not 100% sure about which are the correct Bilsteins I should be using. I already installed new OTS NA B6 Bilsteins that I was told by several Miata club buddies should work great out of the box with my GC 375/250 kit. That was a huge mistake as it is the worst ride I think I've ever experienced in a Miata! So currently on my NA I have the regular Ground Control kit 375/250 springs, new FCM 36/36 bump stops, FM extended rear hats and installed these with the new OTS NA B6 Bilsteins and the car rides horrible. I drove it about 40 miles and parked it knowing I fucked up.

I seem to be getting conflicting opinions on the NB B8 OTS aftermarket replacement shocks. I am under the impression the OTS NB B8 (sport) Bilstein shocks should be a great match for my GC 375/250 springs on my NA. I also just got OEM NB top hats & hardware for the front and the Garage Star 1" rear hats & hardware and was informed I should probably cut my bump stops from 36mm to 30mm.

This is a daily driver and basically I got interested in the Bilstein set up as they are the best quality and last the longest and can be rebuilt etc. I actually loved the way the KYB AGX shocks I used to have rode with this GC kit when they were new but as we all know the AGX don't last for ****. I'm hoping the NB B8 sport Bilsteins with by GC 375/250 kit, NB front hats, 1" extended rear hats will ride similar giving me a nice firm yet livable/streetable ride.

Can anyone help reassure me that I have the right Bilsteins for my set up before I install another set of wrong shocks?! Should I have ordered the OTS NB B6 (HD IIRC) instead of the OTS NB B8 sports? I think the aftermarket NB B8 sport shocks will be good for my set up with possibility of maybe changing to something like 450/300 or 500/325 springs later.

Thanks in advance!

sixshooter

iTrader: (12)

Ride height at pinchwelds?

Horrible how?

nicholaschase29

Hi again. 1990 NA miata. Got my parts in and have been doing some layout and calculations (see attached PDFs). Running Bilstein NA HD's. Planning on running 450/300 springs. I did my due dilligence but want some advice from those with more experience. I've attached some measurements (of both the bilstein and current [tokico blue shock with lowering spring] setups. I'm trying to understand what length spring and bump stop to purchase.

First two attachments are some measurements that I took at full droop with the bilstein and at full compression where i had interference (hit) the frame. For numbers sake I am assuming a ride height of 12.5"

Bilstein HD shock and TSM top had measurements
Full droop: 14.75"
Full Compression at contact: 9.5"
Target ride height: 12.5"
Droop travel (14.75-12.5): 2.25"
Compression Travel (14.75 - 9.5): 5.25"
Distance between top hat and nut at lowest position: 7.5"
Distance shock traveled up inside top hat at full compression: .625"
Remaining travel in top hat (2-3/16" - .625"): 1.562" or 40mm

Current setup - Tokico Blue shocks and tokico lowering springs
Full droop: 17" (compare two pictures of wheels below. One is the current setup (larger gap between fender and wheel) and one is the new setup (smaller gap, NA Bilstein and TSM top hats).

It should be noted that I did not have an isolator under the top hat. I will need to add the isolator which will affect the measuremetns above. I ran the calculations again with an isolator thickness of 0.5" and 1" as shown on the second upload page.

My questions are:

• How much will 7" 300# springs compress in the rear of a NA miata at rest?
• Does my droop and compression travel numbers look ok?
• I should select a bumpstop that will "bind" before acheiving the full compression stroke of 9.5". To do this I will need to adjust my isolator under the top hat or maybe even add washers. https://www.google.com/search?q=fcm+...Jt3w_sfDnWmNiM Something that is 46mm looks like it will work better, although it looks like most all of FCM stops are 36mm on 5X racing.
• Anything you guys are seeing in my measurements or numbers that is worth noting?
  
  
  
  
  
  
  

icepenguin66

I can't remember and have the car stored at another place so can't measure till the weekend but not super low. Probably around 12.5-12.75 inches to wheel hub measurement. Ride was okay on the new smooth tollroad but anything else is bouncy and jarring worse than when I drove my damn SM on the street! lol Even tiny bumps that I'm used to in the neighborhood were really harsh even at 20 mph.

andym

Weird, I have been pretty happy with my nb hd shocks (whichever have the slightly shorter shock shaft) on my na and 550/350 spring rates. I do however have the goodwin feal extended hats front and rear. No complaints so far. My pinch weld heights are about 12.3 front and 12.5 rear.
@ Nicholas, looking at your photos I would be worried about your spring collar sleeve that fits over your shock contacting the top hat on your first bump. I had to trim down my sleeves with a bandsaw to be able to not hit my extended top hats.

mrmonk7663

iTrader: (9)

nicholaschase29

Thanks for the feedback. I do plan on trimming the sleeves, I was just laying everything out first to know how mich to trim.

concealer404

iTrader: (3)

You want the NB Sports. And more spring rate. Those rates are going to have you on bumpstops allllll the time. Which is probably a lot of your issue.

Lukas

Below there is my set of revalved Mt 46mm bilsteins shocks. Spring rates are 350/225. Car is balance is perfect. I feel a lot of grip.
In regards to daily driving it is much better than Oem Bilsteins with stock springs, even on track this set provides plenty of grip and it is still so flat and gentle.
Spring rates are not really high but i decided to revalve shocks to matched them. Last time we compared together with friends If this set is able to combat ohlins ans B16.
We were totaly impressed that car was more fun to drive and more predictable with this set.

andym

The problem with re-valved bilsteins is when you factor in the cost of re-valving them on top of everything else, you aren't far away from xida territory. At that close of a price difference I think it might be worth just getting the better setup from the get go.

Also, the extended tophats on the bilstein sports do help the car feel even more comfortable.

sHOT1980

Honing/updating suspension setup is not always most cost effective way. But you can learn a lot, will understand your car better and will have unique setup for you and your car - with valving/spring rates and etc. (it's a bit offtopic, I suppose).

andym

While true you would have a "unique" setup, unique doesn't necessarily mean better or ideal. Take it from someone who is a bit eccentric and likes to do things unique.

The whole purpose of the bilstein setup was to be a budget oriented setup. Once you factor in the $300-400 cost to have the shocks revalved it starts to get away from being budget oriented and into the territory of just buying xidas from the get go. Sure they can be made to be somewhat ballpark near xidas but then they aren't the budget alternative anymore and will be a compromise in areas.

But, you do you. I don't know the costs on what you paid or what your priorities are. For all I know they were given to you and your entire cost is the cost of a revalve.


With that said, I have a set of off the shelf bilstein nb sport shocks and 550 350 springs and I will stand by them. Been pretty happy so far.

Lukas

In my opinion even if xida has similar price to revalved bilstein it is still better to revalve them.
My black set above kicks ohlins coilovers for na/nb.
Which has to much preload on rebound and compression forces. It is fake sport just only to be stiff and nothing more. They look better at all, but i do not look under chassis.
The main advantage is that i have still possibility to service them easily
Currently i am working on car set with fsd KONI
It will be monotube 46mm bilatein plus FSD on.

Leafy

iTrader: (1)

The Bilstiens when revalved by the right guys can be better or equal to the Xidas. Billy builders, the real pros are hand fitting parts, they're having shims made that are more precise and of better materials than the stamped ones you get in a mass produced shock, spending time dynoing each shock in your set and making tiny shim adjustments to get the pairs matched, and stuff the guy I was considering buying shocks from wouldnt tell me because they all have secret sauce. Its a different product. Xidas you go on 949 click buy and they show up in a week. With custom valved billies you're either sending stock stocks to a guy, waiting a couple months and then they come back, or you have them build off of a circle track billy and you're on the hook for figuring out mounts, either way you've got to figure out your springs.

HowPrayGame

Hi everyone

I have an NB2 with Hard S Shocks and am looking to refresh the suspension re-using the shocks. I am currently running the OEM 16x6.5" Rims but will eventually get a set of 15x8 rims. Running stock front and rear sway bars. I daily the car, and am looking for a decent ride with occasional AutoX and spirited driving.

Here's what I have so far, I am thinking of re-using the front shock mounts to lower the cost, and potentially thinking of cutting the bump-stops in half to purchase only two total, however I don't believe that will work due to the varying resistance in the Integra bump stops.

Summit Racing® Coilover Springs SUM-72-07-450 x2
Summit Racing® Coilover Springs SUM-72-07-300 x2
Stock front Shock Mounts x2
TwoSix Rear Shock Mounts 1" x2
RideTech Delrin Spring Washers 70010828 x8
Energy Suspension Coil Spring Isolators 9.6103G x1
Advanced Auto Coilover & Sleeve Kit 4" x1
Integra Speedthane Shock Bumpers 310 3019-50 x4

Will using the 4" Sleeve kit keep me from needing to cut it down in order to reduce coil on sleeve noise? Also does this look reasonable and have no glaring issues to anybody? I don't care about ride height as long as it performs well and is relatively comfortable.

Thanks

andym

Don't buy the 2 six rear shock mounts. Buy 4 of the extended Maruha shock mounts for $115 shipped. 550 350 is pretty comfy for me and I am on an NA that weighs probably a few hundred pounds less than your stock ish nb2. I would steer you more toward 550 / 350 rates.

nicholaschase29

FWIW I was quoted 17,900 yen ($156) for the Maruha hats shipped a few weeks ago (11/27/18).

I purchased 4 TSM top hats ($175 shipped on black Friday - includes isolators). I am working upper and lower shock mount bushing details now. 5x racing has a kit that uses shoulder nuts however, the hole in the top hat is just big enough for the shock rod to go thru. The upper and lower shock mount bushings have a larger diameter to accommodate the greater OD on the should nuts. i.e. if I used the upper and lower shock mounts without the nuts they would be sloppy and wouldn't center themselves and be concentric to the shaft. I am contemplating turning the top hats to increase the hole allowing the use of the shoulder nut in the kit. Once I figure out mounting of the shaft to the top hat I will be ready to install.

sixshooter

iTrader: (12)

450/300 is plush on the street