help with cam choice with kb190
hydraulics max out about 6k or 6.5k max rpms. dont believe the bunk even if you get NASA approved hydraulic lifters etc.
solids you can go higher.
roller versions have less drag so you get a little more horsepower back and theoretically might run cooler. however they take skill to get them blueprinted properly. i.e. they require a good knowledge of engine building to get all the clearances right etc.
as far as what cam. lower compression = a waste to have high lift. you dont put a .650 lift cam on a 7.5:1 engine for instance. (unless you have it turbo'ed or supercharged, special case)
at 10:1 you could go .480 lift or .520 or maybe a little higher. maybe even .580 or .590. keep in mind however, as you venture up past .520 you will need proper valve springs (spec'ed for the cam) as well as checking all clearances at all rotations of the camshaft. it takes a bit of work. you dont want to throw a .550 lift cam in there with stock springs and find out your springs are binding or rockers hitting or something, then have parts fly around loose in your engine as you are tooling down the road heading to the beach.
cam manufacturers will tout this and that and people will take sides saying my lunati metal is better steel than that crower blah blah blah and my ramp is quicker etc.
at the end of the day what you want is a good amount of lift and duration, dont go way overboard or way underboard either. but make sure you have the springs to match and know how to check valve clearances and rocker clearances etc. if you want to go a little high.