# Cam Profile relation to real world?

I am trying to make a replica Engine but am stuck. I do not know which random number from 1-100 … It is for a turbo charged engine.

Lots of automation values don’t actually correspond to anything, you’ll have to make a guess, the lower the cam profile, the less revs you get but in theory more low end power. The higher it is, the more revs you get and higher power.

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Exactly, it’s a quite simplified way of determining the cam values, in reality both lift, duration and lobe angle will affect how the camshaft works. But generally speaking, a stock turbocharged engine for the street should have a quite mild camshaft = a low number in automation. Fiddle with it until the power, torque and RPM is close to the real engine.

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Another rule of thumb I like to use is this:

For 3,4, and 5-valve engines, whatever the peak power rpm is divide it by 100 and subtract 10. (So if peak power is at 7,000 rpm, I would use a “60” cam).

For SOHC and DAOHC 2-valve engines, it would be divide peak power rpm by 100 and subtract 5. (So if peak power is 5,500 rpm, I would use a “50” cam).

Finally, for OHV engines, it would be divide peak power rpm by 100 and use that number. (So a 4,000 rpm power peak would correspond to a “40” cam).

That’s just a starting point… As Knugcab and Sky-High alluded to, just play with numbers until you find what works best.

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