what are the biggest and deepest wheels i can put on a 69 vw beetle

there really isn't a definate answer. each car is a little different. most of it depends on if the fenders are stock or aftermarket, as they fit different and some aftermarket fenders have a different lip. also are the fenders stock width or widened. if stock, you can fit up to a 18in wheel with the right sized tire. i've seen 20's stuck under one, but it's extremely hard to find a 20 inch rim with the correct offset/backspacing, and width so the tire does not stick out past the fender and look like crap. plus at that size you have to really watch the spacing between the tire and the torsion housing. a 7 inch wide wheel will fit under the back, with the correct offset/backspacing. the only way to find out is to measure, measure, and measure. some big tire shops have a wheel sizing adapter that you can place on your car. with it you can adjust it to different offsets to get the correct size. only problem is finding a wheel with the correct lug pattern with the correct offset. all this is thrown out the window if the rear of the car is lowered. if lowered about the widest wheel that will fit is a 5.5 inch. and that depends on the offset also. my 69 has empi sprintstars, and the 5.5's will NOT fit under the rear fenders. the backspacing is 3.5in on these. if it was a 4 inch they would fit barely. for the front, once again, it depends on what has been done to the car. drop spindles will widen the front track and 5.5 in wide wheels should barely fit. if you have disc brakes, well that widens it out more! best bet on the front is to narrow the beam, then you can fit a wider rim. mine is narrowed 4 inches and i run 5.5 in wide wheels with discs and drop spindles. they fit under the fender by 1/4 inch! they fit, but narrower tires will give more room