Cam Specs

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Producing Quality Computer Tools for Racers and Engine Builders since 1986

Cam Specs

Cam Specs are a very simple way of outlining a Cam Profile as lift so the Cam Profile can be read by a computer program.

Engine Simulation

Our Engine Analyzer programs are Engine Simulation programs that are virtual dynos that allow you to try different combinations of parts (including camshafts) without the time and cost of buying the parts, installing them and running the engine on a dyno every time you make a change.

Our Engine Analyzer program is our simplest engine simulation program and it uses the simplest cam specs inputs. Based on user inputs of Duration (at .050" or 1mm lift, or seat or advertised specs), tappet lift, Rocker Ratio, Valve Lash, centerlines, a ramp aggressiveness rating, a general "cheater"/"non-cheater" description (dwell over nose of cam)

Engine Analyzer Plus is our mid level engine simulation program and allow for more inputs of the cam specs over the basic program, including: The Cam Specs screen also shows the .200 inch duration to help you at choosing settings. The Ramp Rating in the Plus version is a number from 0 to 100, which lets you exactly dial in a ramp to give a desired, say, .200 inch duration for a given .050" duration.

Our Engine Analyzer Pro program is the top of the line program for engine simulation. In addition to the inputs of the Basic and Plus programs, you can import Cam Files in 6 different formats (Cam Pro Plus, Cam Dr, Comp Cams, Andrews, Dr Doctor, S96) to more exactly describe the Cam Profile.

Valve train dynamics is another option.

Variable Valve Timing (VVT) is another option.

Cam File Example - Engine Analyzer Pro ONLY

Here is a brief example of what the file looks like:

0 .000002
1 -.000004
2 -.000006
3 -.000016
4 -.000018
5 -.000018
6 -.000022
7 -.00004
8 -.000046
9 -.000062
10 -.000094
11 -.000106
12 -.000118
13 -.000132
14 -.00014
15 -.000136

What you are looking at in this example, is the base diameter of the camshaft before the lobe. The first number is the degree of the camshaft. The second number is the lift of the specific degree of the camshaft. You will also notice that the numbers are not zero (which you would think it would be). That is because in Manufacturing and Measuring you cannot get a "perfect circle".

Now we will continue on just as the lift of the lobe is started.

91 .00156
92 .00198
93 .002456
94 .002932
95 .003422
96 .003878
97 .0043
98 .004766
99 .005124
100 .005566
101 .006036
102 .006534
103 .00705
104 .007686
105 .008478
106 .00952
107 .011024
108 .01316
109 .016106
110 .020062

Keep in mind that this is an example of one lobe. Depending on the engine there would be at least one intake profile and one exhaust profile for each cylinder. If you want to see an example of a whole Cam File . In Engine Analyzer Pro (and most imported Cam Specs files) there are 2 separate files. One for the intake profile and one for the exhaust profile. But in the CAm Dr. files they have both the intake and exhaust lobes in one file.

Cam Analyzer

The Cam Analyzer program will output Cam Dr ™ , Comp Cams format ™ , and S96 files which can be used in our Engine Analyzer Pro for detailed engine performance and valve train dynamics simulations based on your cam's actual profile. In addition, v3.8 lets you input and analyze computerized cam files for comparison [Cam Dr™, Cam Pro Plus™, S-96™, Andrews™, Comp Cams™, Dr Doctor™], or generate cam files based on simple specs like centerline, duration, tappet lift, etc.

Valve Spring Tester

Our Valve Spring Tester with optional Plus version of the software can also import simple Cam Specs so you don't have to do the math of Tappet Lift times Rocker Ratio minus Valve Lash.