Low serial numbers, early features and condition also plays a big part in price. The ZZ is rated at 6 H.P. on top end. 3600 R.P.M. if i remember. It not the most rare and valuble engine out there but the Z's are some of the best tempered and running Briggs & Stratton ever put out. Along with the A's, B's, 5s, and 6s.
. 106 77 312 42 378 207 253 418