Flyin Miata Koni 1.5 Package

[Munich]

1. My model of MX-5 is: Eunos VR-Limited
2. I’m based near: Munich, Germany
3. I’m looking for help or recommendations on: Spring combinations with Koni Sport Dampers

Hello All,

I’m looking for some help/ pointers regarding spring combinations with the Koni Sport damper.

Ideally I would like the Koni 1.5 suspension package Flyin Miata offer (link to package here: https://www.flyinmiata.com/NA/na-koni-stage-1-5-suspension-kit.html) because:
• I like the additional rear suspension travel it offers (having owned Lotus’ I appreciate the “long travel” philosophy and feel my Eunos could do with more travel on the rear)
• based on the type of driving I do (fast road and no track days), I feel the Koni will be more than sufficient for what I need

FM do deliver outside of the US, but…
• they currently do not have this package in stock
• once I pay for shipping and import tax, I could probably fork out of a Öhlins set-up….
• I am located in Germany and my car (and any aftermarket components) is subject to TÜV, which the FM package doesn’t have

Therefore, I have a couple of questions I hope you can help me with:

1. Does anyone have experience of the FM Koni 1.5 package? Are the spring rates/ bump stops/ increased rear suspension travel, etc… better vs. European available components?
2. Can anyone recommend a spring that works well with the Koni Sport damper?
3. Does anyone know of an alternative set-up which can increase the rear suspension travel? (I have read about using NB components, but the information out there has confused me more than helped me)

I’m looking for a fast-road set-up. I never track the car. Instead I drive on the country roads where the road surface changes from being billiard table smooth to something resembling UK B-roads.

Thank you for any help/ information anyone can provide.

[ast]

TUV does rule out a few popular brands on this site.

My 1996 NA does have a set-up which uses NB top mounts, My setup is long obsolete (Protec shocks, pigtail springs, NB top mount, originally put together by Performance-5), but the ride, 14 years later, remains very good.

I have said, if and when the time comes to change out the shocks (shocks are rebuildalbe ad infinitum, the springs are a bit unknown), I would be looking at Tein. They have TUV certificated sets:

tuv+list+oct19.pdf

Particularly the Tein Street Advance Z

[Munich]

Thank you for the reply.

If you are to have an NB set-up on the rear of an NA, is it as simple as only fitting an NB top mount or are other parts required? I assume the NB rear spring is longer but is the damper also different between the two (I have asked FM this but until now I haven’t received an answer)?

The suspension on my NA looks to be orginial (it still has the Bilstein dampers and the springs are completely rusty) and I want to replay the lot.

[ast]

Order the NB version of whatever spring package you need

Then you need:

NB Top mount
NB " Shock Absorber Upper Bush Mounting Kit, MX5 Mk2/2.5"
MX5parts
PU Bumpstops; ILM list these. I have SuperPro bumpstops, cut in half, for mine

The NB spring is longer, I think slightly narrower diameter. The shocks are different.

NA top mount

NB topmount

The bits you need:

Protech shocks (part of Puredrives), as they came

Puredrive springs (upside down); the bottom of the spring is narrower than the top, because the Protec spring perches.

And assembled with the NB hardware

Somebody else’s Puredrive, on the car

The Koni is a bit old school now. 20 years ago, it was the popular choice, and FM’s main claim was to provide a variable rate spring.

It wasn’t that great quality. FM got a local shop or two to make the springs.

[Munich]

Right. Thank you for the info.

If I have understood you correctly; buy NB dampers/ springs (or coilover set) for the front and rear. Replace all my current NA top-mounts, bumpstops, for NB versions, buy the upper bush mounting kit, and the NB dampers/ springs will fit into an NA. No need to adjust anything on the lower part of the damper where it fixes to the lower suspension arm.

Sounds relatively straight forward…

[Munich]

Just out of interest, what happened to Puredrive (P5?)? I have come across this name in the forums and everyone seems to absolutely rave about them, but they are no-longer available.

[ast]

All straightforward.

Worth mentioning, with old NAs now, the original top mounts may be starting to collapse, and may have needed replacing anyhow. NB top mount is all metal, with seperate rubber pieces.

NB shocks fit no issue into the lower arm.

[ast]

Performance5 has gone. If you research too hard, it leads you to a dark place to conclude its never or extremely unlikely to come back. Puredrives was their first foray, then Sportdrive replaced that.

Puredrive was just a Protech shock, Mazda parts, SuperPro bumpstop and unknown springs (someone put on the forum the rating. At the time, they were a relatively stiff spring, but worked really well with the shock).

Protech for a while tried to sell MX5-specific shocks, with the NATO-spec salt protection, but without springs. Don’t think they bother now.

Had mine since 2008. rebuilt once. I like them. I suspect, objectively, for use on the track, someone would pull them apart, but Protechs are well regarded in the stockcar world.

[Munich]

Are these the shocks?

Find Your Car - Mazda - Protech Shocks Ltd

Protech Shocks Mazda MX5 MK2 Fronts and Rears

[ast]

That’s an interesting find (bit more expensive than 2008 though!). Same manufacturer. The Protech shock was one of a number designed by or involved in by Rod Avon (Avo shocks, GAZ, and another, mostly motorbikes). These shocks all have design similarities as a bit of a trademark.

My Protechs go back to 2008. My understanding was that since then there have been design improvements internally. Least that was the line when I needed some rebuilt, and Protech preferred to do me a discount on a new shock. Iain Gardner (IG Racing) was able to rebuild the shocks using new spec parts.

With my 2008 shocks, the major complaint was the adjuster (knob bade of pot metal, adjustment pivot was brass, shock body; aluminium, a recipe for galvanic corrosion). I haven’t touched those in years, likely seized up, despite the coating of grease I gave them back in the day.

That’s an interesting option, though you need to work out the spring rates needed yourself (rule of thumb; the rears need to be 60% of the fronts, to maintain the MX5’s handling characteristics. The S-Specs, which your VR is effectively, had a little more on the rear springs, in common with the Japan aftermarket, where springs tend to be dialed in for gymkhana courses (where Spax went wrong, by having the spring rates the same, front and rear).

A question is the ID of the springs; are they doing the same as P5 did; Mazda spec at the top, and standard Protech ID at the bottom. P5 did say the Protechs could be had with a spring perch made to fit with a Mazda ID spec spring.

But in your original question, you needed something with TUV approval, which rules out pretty much all the Chinese shocks, with the exception of the notorious Raceland/Rokker brands (if they stll exist). Protech is a small company, their products are made for off-road use. No one really cares in the UK what goes in a car for road use. However, I know Protech do work with the Ministry of Defence, so I assume they are meeting DEFSTAN requirements, and hence they are able to do NATO salt tests (and likely a Protech shock has a NSN number).

Koni, by comparison (and Tein) are huge companies, with probably better quality control. According to IG, there is nothing wrong with the GAZ/Protech/Avo type of shock, what lets them down is assembly, not the design; failures are attributed to contaminants, not component failure (hence he gets them in dry for his racing customers, to then assemble himself).

But in 14 years of use, I had one rear seal weep, which was the trigger for a rebuild.

[Munich]

That’s really interesting.

It’s a bloody minefield this topic, which I suppose is why it is a perennial question on all the forums. I have heard that Gaz have TÜV certification so I’ll take a look there too. All I know for certain is, I want the extra suspension travel on the rear and I will not be playing around with the suspension once it is on the car which is why I am looking for a simple shock/ spring combination (and good, of course…)

Thank you for all the info. It has been very useful. Things are starting to formula in my mind.

[Munich]

Hello saz9961 - sorry, one more question…

With regards to spring rates, is there a general “rule of thumb” to follow when considering what spring rate to go for when seting-up a car up for road use? I understand that the higher the spring rate the stiffer the spring (and therefore ride) will be.

However, is there a spring rate range which is considered good for road use? Or, doesn’t it depend on the damper (i.e. actual spring rates can vary a lot for similar driving characteristic because it depends how it works in combination with a specific damper)?

Thank you.

[ckleanth]

spring rate is matched to a damping value; damping controls the recoil (extension of the shock absorber). what damping value you need also depends on the available shock absorber stroke, the more stroke you have the less damping is required (because more stroke is available that can be used to slow down the extension of the shock absorber)
some companies like ohlins use dual valving, one kicks in at fully closed shock absorber and then it changes to the nominal value when the shock absorber has passed a certain extension (for the sake of an example lets assume halfway the stroke).

[Munich]

Thank you

[ast]

Have a read of:

http://www.tampabaymiatas.net/Misc_Pages/MiataSuspension201.htm

“Stock R” is basically factory S-Spec (VR Limited)

Also, read:

HSD Dualtechs: Best coilover for fast B road use?

I’m using Mk2 top mounts and SuperPro bumpstops (cut in half), which came with their own dustboot. [image] [image] [image]

Puredrives were 350/250lbs. Personally, I find the ride, on a mid-setting, better than mid setting Meister Zeta Pros.

[Munich]

Again, thank you. Interesting read. The rear/ front spring rate ratio is interesting.