Where to buy valve springs

[manga_blue]

FIIK now. They were meant to be a quality brand bought by an honest machine shop through the trade channels. We're trying to confirm that they are really what they were sold as.

[wozzah1975]

Ok,

Sorry for delay, been overseas.

What cams are you running, can you give me the specs?

If you have 3 of those springs broken that is a serious concern, any news on what brand they were?

Cheers,
Woz

[manga_blue]

Here's the group photo for you, woz, plus one already sent away for identification.

Just freakin lucky they all snapped low enough to retain some spring pressure on the collets.

[project.r.racing]

wow. i dont have the words to express what i'm thinking in my head.

[wozzah1975]

Here's the group photo for you, woz, plus one already sent away for identification.

Just freakin lucky they all snapped low enough to retain some spring pressure on the collets.

HOLY F#%K.

I have never seen anything like that, singles maybe, but not in those quatities.

Have you confirmed the brand yet?

What are your cam specs?

Cheers
Woz

[manga_blue]

Pretty amazing, isn't it? It didn't even sound too bad either, one valve ticking, just a mild level of thrash, more like bad valve clearances really. Car felt a bit weak at the top end. That's all. Weird. Definitely not expecting to find all this s#!t.

7 inlet springs failed, 2 exhaust. Valve faces and seats all look good. Spring perches still OK. Retainers on broken springs are very worn.

I don't think I'll ever find out for sure what the springs were, so I won't name the manufacturer. They don't match their pics. I didn't see them before the machine shop put them in. I just think some middle man pulled a swifty somewhere in the supply chain and it was 3 years ago.

Cams are very baby spec. Billets, stock BCD, 252, 9.2mm. MMD lifters, otherwise all stock internals, well balanced, fitted with ACL/ARP. 7600 redline but the engine is built for spread, not peak.

[wozzah1975]

Pretty amazing, isn't it? It didn't even sound too bad either, one valve ticking, just a mild level of thrash, more like bad valve clearances really. Car felt a bit weak at the top end. That's all. Weird. Definitely not expecting to find all this s#!t.

7 inlet springs failed, 2 exhaust. Valve faces and seats all look good. Spring perches still OK. Retainers on broken springs are very worn.

I don't think I'll ever find out for sure what the springs were, so I won't name the manufacturer. They don't match their pics. I didn't see them before the machine shop put them in. I just think some middle man pulled a swifty somewhere in the supply chain and it was 3 years ago.

Cams are very baby spec. Billets, stock BCD, 252, 9.2mm. MMD lifters, otherwise all stock internals, well balanced, fitted with ACL/ARP. 7600 redline but the engine is built for spread, not peak.

What is the spec on the cams measured @.050"? Is the engine turbo'd?

Looking at those specs it would require slightly more pressure than a std spring as they have a reasonable amount of lift, but short duration. Are the cams a known quantity or a one off? Have you actually measures the specs, or are you assuming they are correct to the cam card? Was the installed height measured, or just assumed to be correct? What were the end results in spring rate, both on the seat and at full lift? Is there any rub marks on the springs outside diameter? Was the break at the top, bottom or a mixture of both (this could be a key question, as it will indicate whether the spring is the problem. the chances of having them all installed the same wat are slim)?

For a failure like that something is VERY wrong, either with the spring, or what you are trying to do with them.

They all seemed to have failed in basically the same spot, which could indicate a poor spring, but if the same thing is wrong on all valves it is also possible there is another underlying issue.

If you intend to purchase springs I would pick a rate to match perfectly, and use something in the Eibach range. they're probably over the top, but they're a very good quality unit.

I'm keen to here back your answers, and please PM me the brand, I won't repeat it, but I would like to know to avoid the situation myself.

Cheers
Warren

[ralt]

Hi.
I have seen this type of failure before and it was caused by the spring free length being incorrect on that application. The keepers being worn is another sign of length problems. You are a very lucky man if there is no real damage to other components.

[manga_blue]

Serious questions. Thanks for this, woz.

Maruha F-Cams - well known, but I don't have full specs. http://www.maruhamotors.co.jp/miata/parts/na8fcam.html HLA grind but I eventually got fed up with HLA ticking which was happening occasionally before the F-Cams went in and got much worse after. So MMD lifters went in with clearances 8-10 thou inlet, 12-13 exhaust. Lash caps average around 3.00mm inlet, 2.5 mm exhaust. Lash cap skirt is well clear of collets. Single OEM shim under each spring.

Springs all broke in the same place, 7-10mm from the bottom. That was very lucky because it meant all were still retained by the lower perches and valve guide tops and still had enough length to hold the collets in. No rub marks. The intact springs are all straight, free length 44.5mm. I'd need to re-make a jig to test spring rates again. I never saw them new so don't know what original specs were.

By "installed height" do you mean valve stem above top of valve guide - haven't checked that yet.

Eibach singles look a possibility. Eibach duals look too strong. I don't think I need much above stock. I've got long OHV heritage with A and B series and 105E/107E/109E, then mad twincam fiats that I sheared the lobes off, so I come from that line of thinking that you put as little load on the valvetrain as you can and no more.

Ralt, that 44.5mm free length of the survivors is in the ballpark for the OEM spec of 46.26mm

[wozzah1975]

Serious questions. Thanks for this, woz.

Maruha F-Cams - well known, but I don't have full specs. http://www.maruhamotors.co.jp/miata/parts/na8fcam.html HLA grind but I eventually got fed up with HLA ticking which was happening occasionally before the F-Cams went in and got much worse after. So MMD lifters went in with clearances 8-10 thou inlet, 12-13 exhaust. Lash caps average around 3.00mm inlet, 2.5 mm exhaust. Lash cap skirt is well clear of collets. Single OEM shim under each spring.

Springs all broke in the same place, 7-10mm from the bottom. That was very lucky because it meant all were still retained by the lower perches and valve guide tops and still had enough length to hold the collets in. No rub marks. The intact springs are all straight, free length 44.5mm. I'd need to re-make a jig to test spring rates again. I never saw them new so don't know what original specs were.

By "installed height" do you mean valve stem above top of valve guide - haven't checked that yet.

Eibach singles look a possibility. Eibach duals look too strong. I don't think I need much above stock. I've got long OHV heritage with A and B series and 105E/107E/109E, then mad twincam fiats that I sheared the lobes off, so I come from that line of thinking that you put as little load on the valvetrain as you can and no more.

Ralt, that 44.5mm free length of the survivors is in the ballpark for the OEM spec of 46.26mm

Ok,

Did you replace your cams when you changed to the MMD solids??

If you didn't this is more than likely your problem. HLA profiles are very different from Shim type profiles and cannot be converted without changing both cams AND lifters.

Your car, whilst it may be running ok, will have incorrect opening and closing ramps for the solid lifters. I would suggest this is your problem (assuming you have the HLA cams still fitted), and why your springs have failed.

The installed height of the valve spring is the the height of where the valve spring sits when installed with the valve closed. So the measurement is from the underside of the valve spring retainer to where it sits in the head. The spring manufacturer will quote figures given an installed height, and usually also figures from given valve lift points.
Eg: the figures may be 75lbs @ 36mm, 180lbs @ 12.7mm lift (23.3mm spring height)

I always check valve spring rates on EVERY valve, new or not. And I always completely compress the springs prior to checking them.

Cheers
Warren

[ralt]

Hi.
Do you run bigger valves? if so i would measure the length against a standard valve particularly the length from the valve face to the retainer machining as i still feel the problem is in the valves/springs. I would not be comfortable with a 2mm difference in free length of the springs and wear on the spring retainers.

[wozzah1975]

Hi.
Do you run bigger valves? if so i would measure the length against a standard valve particularly the length from the valve face to the retainer machining as i still feel the problem is in the valves/springs. I would not be comfortable with a 2mm difference in free length of the springs and wear on the spring retainers.

Regardless of what valves are fitted the installed height of the spring should always be checked, even with std springs. And yes, the tolerance is usually +/- .020" (.50mm) so 2mm is far to much difference. Retainers generally don't wear much if at all.

Cheers
Woz

[manga_blue]

I'm learning more about springs than I ever wanted to know. Firstly, let me tell you that spring retainers can wear a lot when they've got a broken spring bouncing around underneath them. The retainer wear is a consequence, not a cause, of spring breaking.

I had an interesting talk with the spring expert today. Two springs can have the same size and same spring rate and one will perform well in a head and the other will destroy itself. It's a matter of resonance, he said. All springs have natural resonance frequencies. When they are operating in a resonance frequency they store energy and additional inputs at that frequency can amplify the resonance to the point of destruction. Think of a wineglass shattering when exposed to a tone of the right pitch.

The MX5 head, he said, is notorious as a dirty head in terms of range and strengths of resonance frequencies produced in it. He knows 5 or 6 instances of MX5 springs breaking as their first harmonic matches natural frequencies within the head, independent of spring rate. Springs for MX5s need to be tuned and tested until they are known to be safe for these heads. This may involve varying wire diameters, coil numbers and tempering while maintaining the same broad parameters of free length, rate, etc. It's not just a simple matter of getting right size and rate.

He thinks my failures are indicative of harmonic failure. I never will know whether or not they were tuned for an BP. It's very likely both Woz and the spring man are right. There's a resonance problem exacerbated by inappropriate cam profile, or vice versa.

I'll be going for the belts and braces solution: known springs (choice of Eibachs, Supertechs or Performance Springs) with a matched cam/lifter solution, whichever Woz and the spring man agree is best. If I have to go back to using bloody HLAs again then I'll just stencil a sign of the cross on the cam cover first.

[sailaholic]

Waz cams are quite economical.... So if you already have solid lifters and you need new springs I'd be changing cams.

Sent from my GT-I9100 using Tapatalk 2

[NitroDann]

300*+

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Dann