Lifters

This is how someone explained these lifters to me a long time ago, something like this: The Rhoads lifter was a unique take on what makes a radical cam not very street friendly....duration. So they devised a lifter that had such a high bleed rate that at lower RPM's the lifter was so lazy that it would not open until 10-15 degrees into the ramp (example) like it would bleed out then finally catch and start pushing the valve at a lower lift even.... At higher RPM's the bleed rate was the same but the time was much quicker so it felt like the lifter wasnt bleeding down at all and giving full duration as well as valve lift, making a wild cam streetable and giving it full potential at higher RPM's. It sounds great on paper but it came with increased lifter noise and wear from what I remember. Crane Hi-intensity came out and quoted the same dual pattern performance without the noise due to a new metering design. I always thought it was a band aid approach but some people really liked them.