Installed spring height

[mats andersen]

THe kent VS42 springs has solid height at 21.9mm. So with installed height, lets say at 37mm and with 12mm valvelift will have 3.1mm left.
So this should be easy sa walking the dog as long as the mailman will bring me that spring tester

mats

[ZeNiTh-PbArM]

Hi,
please note it's possible to build your own spring tester from scratch, using a simple bench drill and a standard weiging scale.
place the scale under the drill chuck, and the spring inbetween
using the lever, lower the chuck until the scale displays the appropriate value. Then read chuck depth on the drill scale, this gives you the required installed height.
all the best,
zp

[mats andersen]

My jk303 cams came in today!!

I finally got my spring tester also. I have tested the Kent springs which seems to be very identical, fortunately.
But it seems I need to go down to 36mm installed height to achieve the installed pressure of 85-90 lbs, and 12mm valve lift at about 200 lbs.

Therefore I must doublechekc one thing.
...the gauge on my tester ranges from 0-300 PSI ??? I expected to see "lbs" there.
Is this the equivalent of lbs somehow? Propably a stupid question for those clearsighted. I thought PSI or pressure pr. square inch was used mostly for gas and fluids pressures/density. And lbs or pounds beeing weight or force regardless of square inches...

The spring tester has an advertised measuring range 0-300 lbs/in...

Just need to make sure my readings are correct and properly done:

thanks
mats

[180OUT]

Quote:

Therefore I must doublechekc one thing. ...the gauge on my tester ranges from 0-300 PSI ??? I expected to see "lbs" there. Is this the equivalent of lbs somehow? Propably a stupid question for those clearsighted. I thought PSI or pressure pr. square inch was used mostly for gas and fluids pressures/density. And lbs or pounds beeing weight or force regardless of square inches...

[mats andersen]

Not sure where its made. I got it from summitracing. Brand is Proform. Tech support told me PSI and Lbs meant the same thing in this case so...
It does sound strange to me though.

m

[slyalfa]

if the test cylnder is 1 sq. inch then it will line up. but you could test it by putting it on a scale and then put a wight on it. and see if they read the same. like a digital bathroom scale.

[mats andersen]

ok, I see. the cilynder within the springtester that are connected to the gauge is propably 1sq in then

m

[slyalfa]

yes.. it should be

[60sRacer]

As with any instrument, you should think of how you might calibrate your new tester. Just reading a gauge really doesn't tell you anything other than all the springs are the same.

Try this: Carefully measure a spring height. Place a heavy weight on it and measure again. Add another weight and measure again. Check the weights on an accurate scale - not just your bathroom scale. Measure length very accurately!

Then repeat the test on your spring machine. Compress to the previously measured lengths, and compare the weight readings with your previous weights. With at least two, you can calculate the correction for your tester gauge.

Now go use the tester and get some accurate measurements.

Robert

[mats andersen]

Hi

yes that would be the accurate way of calibrating the tester.

At 37mm spirng height i got 79 lbs. I contacted Kentcams and asked them to measure a set of springs with their professional equipment at 37mm. To my great relief they got 78 lbs. So My spring tester has now been verified :-) It is pretty accurate.

mats