Dad707, how old are the sparkplugs? They might be getting to old to perform right
How about plug wires, are any of them (especially #4) burnt, they might need replacing, u can get a set of msd wires for about 75 and it will get u about another .5 mpg
Some simple things to check first before you get to in depth
BV heads, P&P lower, windstar upper, comp 218/226, 4.2 bottom end, 3k stall, flow 40's, O/R x-pipe, Pacesetter lt's, Xcal2, 65mm tb, CAI, 8.8 w/ 3.73's, MM LCA's
coming soon: blower cam and intercooled M112
dealer for Ortiz Performance; tunes, cams, etc. PM me!