Cam profile question

[Tony]

This may be a really stupid question but is it possible for to small of a cam to create a lean condition in an engine? Valves not staying open long enough, or not opening far enough to suck enough fuel/air into the cylinders?

Could this create a lean condition or just major lack of power?

[Chris]

The most common cam selection problem is when you don't have enough engine for the cam. A monster cam is going to be a problem if you don't have the compression to support it. Additionally, head selection can also be a problem. If you have heads with monster ports on a small engine, you're going to get poor port velocities which leads to the atomized fuel puddling in the intake tract and then it doesn't burn properly. manifold matching is a big one too.

Bottom line- you've got to match everything very closely and there's very little in the way of a chart that tells you what goes with what. Mostly, it's experience.

[Raylar]

Obviously engines are air pumps that burn fuel. If the engine is not breathing well it will not make good power and will not operate efficiently due to many variuos causes. However can a camshaft alone cause a lean burn in an engine-NO!! Can a fuel delivery problem-YES! Any engine major components such as camshafts, cylinder heads, exhaust, fuel delivery and such improperly sized, improperly installed, misapplied or mismatched will always usually cause a loss of power and efficiency!

Best Regards,
Ray @ Raylar

[paston1]

Cam No, carb or injection yes. All cylinder lean? Burned piston lean?

[PatriYacht]

I've found that, generally, bigger cams require larger jetting. Smaller cams produce more vacuum and better carb signal.