At what valve lift does flow max out on stock LT1 ports? Is this an important factor to keep in mind when choosing a cam?

 

Looking at my before and after flow numbers from Loyd. Looks like the stock ports are done by .600, But the flow increase form .500 to .600 is so small that you might as well call the stock ports done by .500.

 

But a cam that maxes at .500 is only going to hold the valve at .500 a fraction of the time a cam that maxes at .600 will hold it .500+. The second cam will make more power.

 

Jon A has good advice: The stock ports start to max around .500, but doesnt start to really be detrimental until around .600 lift. Here, the more is better philosophy applies somewhat. The more lift, the more air your getting in per rpm, even though the heads dont flow more at say .570 then they do at .500, .570 is still letting more air in, by simple means of the valve being open over peak, longer.