Believe what you want..........
You say rollers are used because, "most stock cams have _much lower lift and much higher duration than that of a cummins performance street cam." Earlier you say, "In a most instances unless you are going with some really high duration, _high lift profiles, in my opinion flat tappets are superior." So when are rollers better, high lift or low lift? Rollers work with long or short duration cams, fyi.
Roller lifters allow for faster valve action than a flat tappet, and you can control it. You want to compare a short duration, medium lift cam that would require high spring pressures in a flat tappet in order to keep the tappet on the cam, which in turn creates friction and wear on the nose of the cam, which then wears the lobes faster. Why did you go to wider lobes??? I dont get it. Have you ever worked in other forms of racing? I have not seen a Cummins cam that has anything close to what I call a fast ramp. We have a fuel bike cam that has around a 1.2 inch base circle and 1 inch LOBE lift, JUST AN EXAMPLE. Can you picture that cam? Do you think that will work with a flat tappet? I WILL BET YOU THAT A ROLLER WINS THAT $50K RACE. Then you can go tell him you will make him a flat tappet cam that will make it faster. lol.... If you are after all out performance, which is what I thought this was, a roller set-up with lower friction, lower oil volume needs which reduces windage, longer life, and allows cam profiles that you cant match, WINS everytime. I will give you our fuel bike cam specs and you come up with a flat tappet that would provide the same valve action and live. You can make EXTREME valve action with a roller set-up in relation to crank angle. In any form of racing that allows roller cam set-ups have you ever heard of someone saying, "jeez, I think I will switch to a flat tappet cam and kick some azz."??? NOPE!!! BUT QUITE A FEW GUYS DO THE OPPOSITE. Fuel type or form of racing doesnt matter. Its all about friction. I dont have all the answers, but I know that if a roller set-up is an option, I want it. Just my opinion, but find me a engine builder that says if you want the most power possible to use flat tappets.
You say rollers are used because, "most stock cams have _much lower lift and much higher duration than that of a cummins performance street cam." Earlier you say, "In a most instances unless you are going with some really high duration, _high lift profiles, in my opinion flat tappets are superior." So when are rollers better, high lift or low lift? Rollers work with long or short duration cams, fyi.
Roller lifters allow for faster valve action than a flat tappet, and you can control it. You want to compare a short duration, medium lift cam that would require high spring pressures in a flat tappet in order to keep the tappet on the cam, which in turn creates friction and wear on the nose of the cam, which then wears the lobes faster. Why did you go to wider lobes??? I dont get it. Have you ever worked in other forms of racing? I have not seen a Cummins cam that has anything close to what I call a fast ramp. We have a fuel bike cam that has around a 1.2 inch base circle and 1 inch LOBE lift, JUST AN EXAMPLE. Can you picture that cam? Do you think that will work with a flat tappet? I WILL BET YOU THAT A ROLLER WINS THAT $50K RACE. Then you can go tell him you will make him a flat tappet cam that will make it faster. lol.... If you are after all out performance, which is what I thought this was, a roller set-up with lower friction, lower oil volume needs which reduces windage, longer life, and allows cam profiles that you cant match, WINS everytime. I will give you our fuel bike cam specs and you come up with a flat tappet that would provide the same valve action and live. You can make EXTREME valve action with a roller set-up in relation to crank angle. In any form of racing that allows roller cam set-ups have you ever heard of someone saying, "jeez, I think I will switch to a flat tappet cam and kick some azz."??? NOPE!!! BUT QUITE A FEW GUYS DO THE OPPOSITE. Fuel type or form of racing doesnt matter. Its all about friction. I dont have all the answers, but I know that if a roller set-up is an option, I want it. Just my opinion, but find me a engine builder that says if you want the most power possible to use flat tappets.