I did some homework,,, think about the IDrive??? It replaces the torsion spring, makes the opener work very hard. Word is IDrive's don't last that long, but I don't know that first hand??? The hot ticket is the Raynor / Liftmaster "Jackshaft" type opener; you keep your torsion spring. Works great so far. Then you can lift up the rails closer the the roof....within Inch's.... check it
If you boy's don't have room for your sports cars,,, maybe we'll just have to keep them at my house....
http://www.aaadooropeners.com/jackshaft.htmhope the pics work