Lift is certainly very important to consider, but the duration is the number you really need to be careful with. It's not necessarily how far you open the valves, but how long they stay open. With factory flat tops with no valve reliefs, you can leave the lift stock and you'll have problems with inerference probably around 240 degrees duration @.050", possibly less. Even though the piston is in the hole at TDC, you're not talking more than .150". The valves open on the order of around .400" on a stock engine. Stretching the duration out even with a mild lift with no valve reliefs and you're asking for trouble. Wanna run a large by huge cam that's horribly mismatched for your application? Go for it. But just know you'll need to have valve reliefs cut into the pistons to make it happen unless you go with a different piston. And if you do that, you may as well make the entire engine package match. It will run much better in the long haul.