off the trailer car went 2 tenths and 2 mph slower. changed carb spacer to a 1" open from a 4 hole tappered and picked up .5 mph in 1/4 but lost .5 in the 1/8 with same et. changed jetting to 87/96 from 86/94 ran almost identicle et/mph. carb seems insensitive to jet changes,so i put 90/98 jets in and lost 2 mph and one tenth,but put some color on plug,grey. plugs have been white up to this point. ran into EDDIEB there,great guy. he suggested smaller high speed air bleeds,i agree. fuel pressure thru the traps was 7psi. any ideas?