Hi! I am going to bid on 3 mid size and 1 small contract. They want me to mulch the grass...but I don't have big engines on my mower. Is a 23 hp 52" mower could be enough or I should have a big block engine? The lawn will be mow every week and no fertilizer are applicate on the lawn. If 23 hp is not enough, How much should be enough? P.S. Is diesel better than gas to mulch? Thanks!