[Keithc8]

This is a no brainer with the rpm range that you want to operate the engine in. With the hydraulic roller you can run the same duration as the flat tappet and fill the cylinder more because you can have a more aggressive lobe because of the roller. If you wanted to turn the engine 7000 rpms then I would do the flat tappet camshaft because it will rpm better than an hydaulic and last longer than a solid roller camshaft. If you are racing only or have no problem checking the lifter after about 5000 miles and checking the lasg for lifter wear ever now and then the solid roller is the best.
If the flat tappet was the best way to go on an engine that was going to turn no more than 6000 rpms then the current cars would have them and they don't. Ther hydraulic roller makes more power with less friction which is what you are looking for. You can run a smaller camshaft with the hydraulic roler than the solid flat tappet and make the same power but have more drivability and vacuum plus you do not have to worry about a lobe going flat or have to break the damn thing in. Seem pretty simple to me. Good luck, Keith