[elmariachi]

I would think you are only limited by whatever contact your headers might make in the engine bay (remembering your sidepipes are connected too), the clutch linkage and radiator hoses. If you loosen the mounts and go up slowly watching these items, you should be able to get an inch or maybe even two (with the hood open.) On my car I would not have to loosen the rear trans mount but you may have to.