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brian schuetta · 01-24-2019, 10:28 AM

Something I have thought about when selecting a cam was the LSA. It is said the narrower LSA is used in an engine that's under valved. But when you are talking the same size engine with a 325 cfm carb vs a 750 cfm carb is the engine still under valved. In other words if a 305 with 1.84/1.5 valves is under valved with a 750 cfm carb is a 305 with 1.72/1.5 valves and 325(?) cfm less under valved or is the situation worse because of less cfm? I thought the answer was obvious but then I've been wrong before. I was lucky with the 4bbl combo to have someone share a grind number with me that at the time was very good.

01-24-2019, 10:28 AM	#4
brian schuetta Member Join Date: Apr 2005 Location: san antonio tx Posts: 255 Likes: 5 Liked 28 Times in 15 Posts	Re: Dime Rocket Economics Something I have thought about when selecting a cam was the LSA. It is said the narrower LSA is used in an engine that's under valved. But when you are talking the same size engine with a 325 cfm carb vs a 750 cfm carb is the engine still under valved. In other words if a 305 with 1.84/1.5 valves is under valved with a 750 cfm carb is a 305 with 1.72/1.5 valves and 325(?) cfm less under valved or is the situation worse because of less cfm? I thought the answer was obvious but then I've been wrong before. I was lucky with the 4bbl combo to have someone share a grind number with me that at the time was very good.