- My model of MX-5 is: NC 3.5 Sport Tech PRHT 2.ltr
- I’m based near: South Worcestershire.
- I’m looking for technical help or recommendations on: Broken spring replacement type.
I have a broken NS rear shock spring.
The car has Bilsteins on it but I’m a little confused about what type of spring I need.
The only information I have is from looking at the shock/spring.
I assume (like other cars) that those coloured dots mean something, but I know not what!
Can anybody advise please? I need to sort the bits ASAP as it’s my daily drive.
The car may have been lowered by 30mm at some point (previous owners) as it doesn’t have that 4x4 look about it.
BTW, no, that isn’t a shock leak, it’s water used to clean the spring!
Cheers.
Rick.
They look like stock springs with the paint dots. Mx5 parts has a large selection for all nc standard and bilstein. Worth a look. https://www.mx5parts.co.uk/mx5-parts-mk3-suspension-steering-shocks-springs
1 Like
Coloured dots I believe are usually a Quality Control type mark, or a check/confirmation.
I don’t believe they mean anything specific, certainly not in terms of spring type.
1 Like
Thanks Chaps.
MX5 Parts are my default supplier 
The bit I’m still not clear on is, has this car been lowered at some point in it’s life?
Is there a thread anywhere that can give me some dimensions, such as hub centre to wheel arch?
The garage only knew about “16 or 17 inch wheels mate”.
I certainly don’t want it any lower, the Hereford pot holes would completely eat it and I wouldn’t be able to get it on my drive!
Did the Sport Tech come, as standard, lower on the Bilsteins?
I don’t think I’ve ever seen any mention on that anywhere.
Yes, I know, a bit of rear wing work needed!
Just washed, hence grotty discs.
Cheers,
Rick.
That looks like bilstein standard ride height. Here is a pic of mine before I did the coilovers, completely stock. If you looks at the front springs you can just make out the paint dots.
1 Like
Cheers Chap.
I’ll try and get the originals.
MX5 Parts are out of stock…
Rick.
VAG group use the same spring ID system - up to three colors of paint dot on the springs.
The basic logic is that dealers can identify the exact spring you need - but it is hard for anyone
to work out the exact spring rates because they are not written on the springs.
1 Like
Your NC2 will have had a revision over the NC1 models, it appears by dropping the front lower. Doesn’t mention the rear though.
“The front suspension geometry was revised by altering the ball joints’ vertical pivot position, lowering the height of the front roll centre by 26 mm”
Will be Bilsteins if a Sport Tech, the NC1’s were much higher than that even on Bilsteins.
1 Like
Thanks for the responses chaps.
Problem now solved.
It did have genuine, non lowered rear springs.
Unfortunately, I could only get originals from a Mazda dealer. MX5 parts had a “6-8” week lead time.
To be fair, there wasn’t actually that much difference in prices. They also supplied the gators too.
As the photos show, genuine rear, non lowered Bilsteins have a green and yellow dot.
Also of note, both springs show the potential break points, so it was only a matter of time before both would have gone anyway.
I couldn’t get the bump stops in the time required, but they turned out to be fine.
The car’s done 135k, but I only know the previous 45k, so no idea if they were original springs.
Right, save up for the front ones over the next few months…
Rick.
4 Likes
My rear o/s broke at the same place after 80k and 10-y-o. Probably broken for some time so 65-70k is about the mileage they do.
1 Like
