Engine bar clamps are expensive. I used armoured cable cleats, different sizes available depending on the girth of your bars. These mounted ontop of a bed of wrap or two of insulation tape save you tons of cash. They cost pennies. Have a look at mine at Squires if you're going. If you know width of your engine bars before the meet let me know ill fetch some along (I sell electrical gear for a living ,so can get them cheap).