Performance Trends, Inc.

Producing Quality Computer Tools for Racers and Engine Builders since 1986

Valve Spring Tester v1.1 for Windows XP/Vista /7/8/10

Computer Program, Electronics and Sensors to Measure Valve Spring Rates, Seated Force, Open Force, etc.

As Seen on TV's Motorhead Garage     to view clip of show


Manual USB Spring Tester                 Automatic USB Spring Tester
         for specs on our valve spring testers.

"At Gray Motorsports, when we implemented The Performance Trends Auto Spring Tester last season, we saw an improved consistency in our engine performance and greater reliability of our valve springs. It has been helpful with our NHRA Mello Yello Fuel Funny Car that Johnny drove last season and our Pro Stock program this season. We even had a situation when we caught a valve spring that would have failed before it got put into service. This tool has proven to Gray Motorsports it is the best way for us to test valve springs for our race teams."

Endorsed by: Gray Motorsports - Johnny Gray, Shane Gray

Our Valve Spring Testers are available either as a Manual tester or Automatic (pneumatic) tester.  The automatic tester can be outfitted to provide up to 2500 lbs of force (or higher) to precisely test the huge springs used in today's top drag racing classes, as used by Gray Motorsports.  The manual tester can be purchased with either a very easy Basic version of the software, and a full featured Plus version.  The automatic testers all come with the Plus version.  The screens below show the 2 software versions.

Basic version of Software (very simple)


The Basic version shown above is just this screen.  It lets you test springs one at a time and very accurately determine Seated Force and Open Force at spring lifts you enter, Spring Rate, Binding Height, and Bind Height Clearance, and Non-Linearity in percent.


Plus version of Software (all features)

The Plus version lets you record, save, analyze, compare, graph, report and print your results, saving you time and providing accurate and professional results.  Results include:

  • Spring Rate
  • Force at Seated Spring Height
  • Force at Open Height
  • Height for a user defined spring force
  • Bind Height
  • Bind Height Clearance (between Open Height and Bind Height)
  • Linearity (non-linearity)  to see graphs illustrating this calculation.
  • Damping  to see graphs illustrating this calculation.
  • Test Cycle Time, Test Open Rate, Test Closing Rate

Other screens from the Plus version are shown below.

The Valve Spring Tester can be ordered with either the Basic or Plus software.  Basic versions can be easily upgraded to the Plus version for $100.

Other Plus features include:

  • You can select if intake specs (like open height) should match exhaust specs.
  • Program can determine open height from cam specs like Tappet Lift, Rocker Ratio, Valve Lash, etc.
  • Program can screen all results for up to 3 user defined limits, like if Spring Rate falls outside a range of 300 to 350 lbs/inch.
  • You can search results (like a data base) for certain words in the comments, test date, Customer name, etc.
  • Showing results for Spring Height (like measured with a ruler) or Spring Compression (measured from Seated Spring Height).
  • Professional printouts of reports, which can even include your company's logo.  
  • Export data as ASCII files for use in other programs.  Version 1.1B and 1.1C allows for browsing to find or create file names and exporting in Excel format.
  • Shim Report to quickly find shims for a set of springs you have measured which meet your Seated Force and Bind Clearance requirements (v1.1B or C only).
  • Valve Lift input in the Quick Check screen, which is similar to the Shim Report above, but for doing this 1 spring at a time (v1.1B or C only).
  • Make reports of spring heights which produce various forces, like at 10 lb increments (v1.1C only)
  • 4 Test Types to allow for springs with "bent" force curves ( like 2 stage springs), or not compressing the spring in to coil bind (v1.1C only)
  • Assign individual Seated Spring Heights for each spring to allow for variations in heads, valves, retainers, etc. (v1.1C only)
  • Much more.
      to see all the new features in v1.1B and 1.1 C. 

Here's a printed report from our Automatic Valve Spring Tester, showing its outstanding repeatability (highlighted in yellow).  It also shows where your company logo can go, in the upper left corner.

to view the PDF file of this report with better detail and quality.

Page from v1.1B User's Manual Describing Shim Report
Shim-Report-Manual-Page.gif (136753 bytes)  click image to enlarge    to see all the new features in v1.1 B & C. 

Page from v1.1C User's Manual Describing 4 Test Types for Testing Springs
  click image to enlarge    to see all the new features in v1.1 B & C. 

Page from v1.1C User's Manual Describing Individual Seated Spring Heights
  click image to enlarge    to see all the new features in v1.1 B & C. 

Page from v1.1C User's Manual Describing Individual Seated Spring Heights, cont.
  click image to enlarge    to see all the new features in v1.1 B & C. 

Here's a couple of calculations unique to Performance Trends' spring analysis: damping and non-linearity.  These are illustrated in the graphs below.

Damping lets you rate the damping effect of dual and triple springs with dampers.  The higher the internal damping in the spring (like a shock absorber), the more heat that is generated, but also the better chance of keeping the valve train under control by avoiding spring surge.

Non-Linearity lets you see if the springs are linear or not.  Sometimes springs are designed to be non-linear, and now you can actually measure 'how much'.



Performance Trends Valve Spring Testers

Manual USB Spring Tester                                           Automatic USB Spring Tester

Spring Tester Specs:

Manual Spring Tester:

  • Spring Height measurement range:  .65 to 2.85 inches (16.5 mm to 72.4 mm) *
  • Force Range:  0 to 1000 lbs (0 to 450 Kg)  **   ***

Automatic Spring Tester:

  • Spring Height measurement range: .25 to 4.00 inches (16.5 mm to 101.6 mm)  Greater heights and .000 minimum height are optional.
  • Force Range:  0 to 1000 lbs standard (0 - 450 Kg) with 90 psi air pressure  (1600 lbs force can be generated with 130 psi air pressure and optional 2500 lb load cell) **   ***   ****

*  We have a special load cell mount which can provide for springs up to at least 3.30" height, part # SPV-L3+  Depending on the tolerance of the actual press, this could be 3.40 inches or more.

** Higher range 2500 lbs load cell available, part # SPV-LCNS .  The Manual Tester needs to be bolted securely to a bench top for testing high rate springs.  The Automatic Tester does not need to be bolted down, but does require shop air pressure, 90-150 psi.

*** Special 0-250 lb and 0-500 lb range testers are available (part # SPV-LCNS) for lighter duty springs for the same price.  As these are more sensitive instruments, you must be careful not to over-range these testers.

**** SPV11A-HFO  High Force Option for the Automatic Spring Tester replaces the standard pneumatic cylinder with a much larger unit, 2500 lb load cell, and other modifications to accommodate this larger cylinder  (2500 lbs force can be generated with 130 psi air pressure and measured with optional 2500 lb load cell).  This is the tester used by Gray Motorsports and others needing to test huge valve springs.


Power Tech PT-200 Software and Electronics Upgrade Kit:

Our software can be added to a Power Tech PT-200 spring tester using our USB interface.  for details.


Valve Spring Tester, Complete Kit:

We offer a kit where you can build your own spring tester.  The Valve Spring Tester, Complete Kit (part # SPV11C-STK) with calibrated Load cell and 3" length sensor. The parts shown below are designed to be fitted to a standard "1 ton" arbor press, with an opening of about 5.25 inches (130 mm).   for an example.  The press will require some machining, typically drilling of holes and tapping of some holes.  This kit includes EVERYTHING except the press.  This kit only makes sense if you live overseas and want to avoid the expensive shipping (which can be as high as $400 or more) for the heavy 55 lb (22 Kg) complete test stand.  Shipping for just this kit can be as low as $80.

Valve Spring Tester Kit.jpg (313181 bytes)   click image to enlarge it


What You Need:

Computer with Windows XP, Vista, Windows 7, Windows 8, Windows 10.  The Automatic Valve Spring Tester also requires clean shop air, from 90-150 psi.   Less pressure is adequate if you are doing lower rate springs. 


What You Get:

Program CD with user manual in PDF format on the CD. Example test files preloaded in the Example library for you to start with.  Tester includes tester shown above, cable to connect to computer's USB port (which is what powers the electronics), factory calibration and "quick start" sheets.  User manual is on the CD as PDF file.

More Information, Download Demo:

to see all the new features in v1.1C, released Oct 2017. 

to go to our Demo Downloading page to download a FREE Valve Spring Tester Demo.


for prices.

for financing info on paying on installments.

for User's Manual.

for customer feedback.

for our On Engine Valve Spring Seat Pressure checker

To Order:

Call 248-473-9230. Visa, Mastercard, Am Exp and Discover accepted.