What is the Katech Whistler?

The WHISTLER is an electronic device that instantly determines the compression ratio of virtually any engine.

Using the WHISTLER is easy, just remove a spark plug and screw the WHISTLER adapter in its place. Enter the number of cylinders, CID, and temperature of the engine into the WHISTLER. Then, bring the engine to TDC and the unit will display the compression ratio to the nearest tenth of a point.


Used by these sanctioning bodies:

All you need is a low volume air source and a 120V AC supply

Included with the WHISTLER:

12mm spark plug adapter optional


Order online

Order replacement adapters





















Is your whistler in need of calibration or repair?

For calibration or repair services, fill out the request form and send to the address below.


Katech Inc.
Whistler Repairs
24324 Sorrentino Ct.
Clinton Twp., MI 48035

NOTE: Whistler repair/calibration services will be offline until 9/1/15.  Any Whistlers sent in now will not be started until then.

Calibration/repair prices:

Calibration only: $300
Repair and calibration: $400 plus parts