Gear drives are no more accurate than a good timing chain. The crank and cam sprokets will stay in sync and in phase as long as the chain does not skip a tooth. PERIOD Because of the design of the chain and the nature of how the engine runs, it's impossible for the cam timing to vary from the crankshaft. While the engine is running, even of there's slack in the chain, which there is, even on a new one, the chain is always tight on the driver's side of the engine, because the crankshaft is pulling the chain and cam gear right along. There's no slop on the drive side of the chain. Want proof? Fire that pup up without the timing cover and see for yourself. I've done it quite a bit in diagnosis. Gear drives have only one advantage over a chain. They last longer. And with a high end chain and gearset, even that becomes arguable. A chain will eventually fail, although a good high quality billet double roller will probably not fail in your lifetime. Also, another known problem with gear drives is that they set up some freaky harmonics back through the entire valvetrain and can cause havoc with some forms of electronic ignition up through the distributor gear. They have even been known to cause some frequency interference with valvesprings at high RPM. THAT is something you don't wanna play around with. Can you say dropped valve @ 7K? Even computerized engines cannot run them because of this phenomena. They will slap booger up the knock sensor. What do the big boys run? Pro Stock, Funny Car and Top Fuel all run belts and chains. Ask around even the smaller classes. Nobody seriously into racing runs a gear drive, because the serious racers all know. Gear drives are nothing more than a gimmick fad to get into your wallet. I'll take a good chain anyday. Simple as that. Thank you. Drive through.