Valve spring tester ????

[David Redszus]

Why is a spring tester device necessary?

A simple vernier caliper is all that is necessary to determine:
free length
spring rate
nose force
seat force

Using an excel spread sheet, the above can be calculated with almost the same accuracy as any spring tester device.
The exceptions are bee hive style, and tapered wire types.

[ProPower engines]

Why is a spring tester device necessary?

A simple vernier caliper is all that is necessary to determine:
free length
spring rate
nose force
seat force

Using an excel spread sheet, the above can be calculated with almost the same accuracy as any spring tester device.
The exceptions are bee hive style, and tapered wire types.

That may be. Anything can be calculated mathematically in theory but practically you need a method to confirm the springs rates. We have I am sure all had springs that did not test as they are suggested by the manufacture and while we can use a math figure a guys still needs to confirm what he is using in the end.

[turbo camino]

Why bother measuring anything when you can just look up the specs in a catalog??

[ProPower engines]

Why bother measuring anything when you can just look up the specs in a catalog??

I guess you don't use or test many sets of valve springs

[turbo camino]

Why bother measuring anything when you can just look up the specs in a catalog??

I guess you don't use or test many sets of valve springs

Well if a company sells parts that don't meet the advertised/published specs then people will stop buying from them and they will either improve or go out of business. Calipers and the catalog FTW!

Of course, if you ever end up with a set of unidentified springs (or used springs of unknown condition), you should just throw them away. With no part number to look up there's no way to find out what they are. Oh well.

[ProPower engines]

Even springs that are boxed and ID'd as such still need confirmation regardless. Seen too many issues over the years
to get complacent with valve springs that are supposed to be as advertised. Msot street stuff is FT cams these days
cause most guys don't have the cash for a proper roller set up and even then and hyd roller lifters is suspect to quality
and if you have a specific lifter type and run too much open noisey valve trains result But then again how do you know they are not boxed wrong??? Seen that several times and without a way to test the springs accurately I would have never know
but sure as shit floats I would have been blamed for the screw up if I did not check and a cam/lifter failed and the customer had some one else look at it that has a spring tester. And how do you even come close to knowing if the rates are correct
with the retainer in place on the spring?? When tested your using a sp0ec supplied by the spring maker right. And lots of shops never even think of how much that retainer changes things like on a dual or triple spring.

If we have learned anything in this business its to never believe whats in print. Check and confirm before installation

and as for your comment about stuff not being right and guys stop buying it then why is Comp still selling FT cams

[turbo camino]

Snark doesn't come through well in text, does it?

If everybody checked Comp parts as closely as they should they'd long ago have run out of customers. They can't even get the simple things right like spring seats. The last 'set' I bought were as much as .010" different on every single dimension, I just make them myself now. I can work sloppy on my junk machines and end up +/-.001 on something like spring locator/seats.

[ProPower engines]

Snark doesn't come through well in text, does it?

If everybody checked Comp parts as closely as they should they'd long ago have run out of customers. They can't even get the simple things right like spring seats. The last 'set' I bought were as much as .010" different on every single dimension, I just make them myself now. I can work sloppy on my junk machines and end up +/-.001 on something like spring locator/seats.

Sure they do cause they are intended to be used with their springs. Mix a spring and locator and that issue comes up every time.

[David Redszus]

Why is a spring tester device necessary?

A simple vernier caliper is all that is necessary to determine:
free length
spring rate
nose force
seat force

Using an excel spread sheet, the above can be calculated with almost the same accuracy as any spring tester device.
The exceptions are bee hive style, and tapered wire types.

That may be. Anything can be calculated mathematically in theory but practically you need a method to confirm the springs rates. We have I am sure all had springs that did not test as they are suggested by the manufacture and while we can use a math figure a guys still needs to confirm what he is using in the end.

And how do we know if the spring tester device is correct and accurate? Has it ever been calibrated? And how was that done?

While some calculation formulas may be incorrect, so can measurement devices which need to measure both displacement and force accurately. Now to determine spring rate, we still have to do a bit of math.

How does a valve spring tester work for suspension springs or fuel injector springs? How about springs in tension?

Using a vernier and calculator, I can quickly spot check and determine the specs for almost any spring. If I had to measure and sort several hundred springs, I would use a spring tester.

[ProPower engines]

Most of us are concerned about the calibration accuracy of our testers and that said were endeavor to maintain a
standard of accuracy but simple comparison is not enough in my opinion. A test rig of what ever type is used must
be designed to test in a specific range like all test fixtures.

After its all said and done we used to get springs in bulk years ago. We would get them in box'x of 100 and test every spring and even though they were from the same manufacture I could get 20 lbs difference in both a set installed height and an open calculation and based on the manufactures spec for the springs of +/- 5 lbs that was too much of a change. And while
the suspect spring wire sizes were also checked and found the same size the material quality and heat treat were then suspect. The resultant " light springs " were returned as defective. And having this same talk about testing springs it was
then determined anything mass produced has a tolerance level and it would never be found with out testing on
a accurate testing fixture such as a quality spring tester

[turbo camino]

Using a vernier and calculator, I can quickly spot check and determine the specs for almost any spring. If I had to measure and sort several hundred springs, I would use a spring tester.

I have a new set of springs here in an unmarked box. What is their pressure at 1.85" outer/1.75" inner installed height?
Outer: 1.552" OD, .207" wire, 2.595" free height, 5 turns
Inner: 1.030" OD, .142" wire, 2.345" free height, 5.5 turns

How can you possibly get any usable data just from that without knowing anything about material or temper? What caliper measurements determine which springs in the set need more or less shim to equalize the seat pressures?

[hoodeng]

I have a Rimac digital that has been good for years, i run the Crane calibration spring weekly, all good. If it ever failed for any reason,and as it is no longer available i would get the Performance Trends + tester. The only thing about the Rimac is that it came with a gang of AA battery's to run the thing, I got sick of buying economy packs of battery's and put a sealed Gel 12V battery in it and charge once a month or so, i know i could hard wire it but the last thing i need is a transformer having a dump.

As others have done i test every spring that goes into an engine that is done here regardless of manufacturer or package label.

Cheers.

[ProPower engines]

Using a vernier and calculator, I can quickly spot check and determine the specs for almost any spring. If I had to measure and sort several hundred springs, I would use a spring tester.

I have a new set of springs here in an unmarked box. What is their pressure at 1.85" outer/1.75" inner installed height?
Outer: 1.552" OD, .207" wire, 2.595" free height, 5 turns
Inner: 1.030" OD, .142" wire, 2.345" free height, 5.5 turns

How can you possibly get any usable data just from that without knowing anything about material or temper? What caliper measurements determine which springs in the set need more or less shim to equalize the seat pressures?

Well said
That is my point exactly and the big issue come in checking pressures near coil bind and trying to maintain a min. clearance between coils etc etc etc.
Its always been my opinion that testing them is best. Not to mention after a freshen how would you test and see if they are reusable.
Just saying it pays to test springs bottom line is know or get bit one day.
Enough said

[David Redszus]

Using a vernier and calculator, I can quickly spot check and determine the specs for almost any spring. If I had to measure and sort several hundred springs, I would use a spring tester.

I have a new set of springs here in an unmarked box. What is their pressure at 1.85" outer/1.75" inner installed height?
Outer: 1.552" OD, .207" wire, 2.595" free height, 5 turns
Inner: 1.030" OD, .142" wire, 2.345" free height, 5.5 turns

How can you possibly get any usable data just from that without knowing anything about material or temper? What caliper measurements determine which springs in the set need more or less shim to equalize the seat pressures?

Well maybe we can't, but we can try.

Outer
Rate =218.5 lb/in
Seat force = 162.8 lbs
Avail lift = 10.2 mm
Nose @ 10.2 = 250.5 lbs
Frequency = 617 Hz
Seat stress = 77,140 lbs
Nose stress = 118,721 lbs

Inner
Rate =151.5 lb/in
Seat force = 90.2 lbs
Avail lift = 17.5 mm
Nose @ 10.2 = 194.6 lbs
Frequency = 510 Hz
Seat stress = 88,585 lbs
Nose stress = 191.160 lbs

If we have the true valve stem height, and correct spring installed height, we can determine shim stack for seat force.
With actual valve lift per cam lobe, we can do the same for nose force.

Given the weight of each spring, valve train weights, valve acceleration and rpm, we could then determine the threshold of valve float and probable valve bounce.

Given the above data, which spring is most apt to lose free length and or break first?

The largest factor that affects spring rate and resultant forces is wire diameter. Wire diameter must be measured
carefully and the wire inspected for corrosion pitting, wear areas due to rubbing, and wire nicks.

Most spring manufacturers use high quality wire which is quite similar in physical properties. Most, but not all.

[GARY C]

Using a vernier and calculator, I can quickly spot check and determine the specs for almost any spring. If I had to measure and sort several hundred springs, I would use a spring tester.

I have a new set of springs here in an unmarked box. What is their pressure at 1.85" outer/1.75" inner installed height?
Outer: 1.552" OD, .207" wire, 2.595" free height, 5 turns
Inner: 1.030" OD, .142" wire, 2.345" free height, 5.5 turns

How can you possibly get any usable data just from that without knowing anything about material or temper? What caliper measurements determine which springs in the set need more or less shim to equalize the seat pressures?

Well maybe we can't, but we can try.

Outer
Rate =218.5 lb/in
Seat force = 162.8 lbs
Avail lift = 10.2 mm
Nose @ 10.2 = 250.5 lbs
Frequency = 617 Hz
Seat stress = 77,140 lbs
Nose stress = 118,721 lbs

Inner
Rate =151.5 lb/in
Seat force = 90.2 lbs
Avail lift = 17.5 mm
Nose @ 10.2 = 194.6 lbs
Frequency = 510 Hz
Seat stress = 88,585 lbs
Nose stress = 191.160 lbs

If we have the true valve stem height, and correct spring installed height, we can determine shim stack for seat force.
With actual valve lift per cam lobe, we can do the same for nose force.

Given the weight of each spring, valve train weights, valve acceleration and rpm, we could then determine the threshold of valve float and probable valve bounce.

Given the above data, which spring is most apt to lose free length and or break first?

The largest factor that affects spring rate and resultant forces is wire diameter. Wire diameter must be measured
carefully and the wire inspected for corrosion pitting, wear areas due to rubbing, and wire nicks.

Most spring manufacturers use high quality wire which is quite similar in physical properties. Most, but not all.

How would one know if thats anymore accurate than a valve spring tester?
How do you calibrate it?
What do spring manufactures use to confirm their spring specs?