HI TVT YOU WILL NEED A HIGH LIFT SOLID ROLLER TO GO INTO THE HIGH 6'S NOW ALL YOU NEED IS THE RIGHT COMBO.I BOUGHT MY CAR LAST OCT. AND HAVE NOT ADJUSTED OR CHANGED ANYTHING ON IT. NOT EVEN ADJ. TIMING ONLY CHANGED PLUGS AND OIL AND FILTER, AND YES THE ONLY RACING OIL ON EARTH VALVOLINE.ACCORDING TO WIDOW OF OWNER IT IS A 20 OVER 360 SOLID ROLLER WITH A ELDO. AIR GAP WITH A PROFORM 750.AND 202 J HEADS , I BLEW A REAR U JT AND CRACKED THE CASE ON TRANS SO I REPLACED THE CASE, IT HAS A 8 IN. 5000 STALL CONVERTER IN IT A CHEATA REVERSE MANULE VALVE BODY AND TURBO ACTION SHIFTER, 8 3/4, 488 GEARS SS SPRINGS MOVED IN FOR LARGER TIRES AND ADJ. SNUBBER. 31/10.5/15 MT SLICKS.I CAN RUN 6.95 TO 7.12 , AND 1.46 TO1.53 60FT. TIMES. ALL NIGHT LONG WITHOUT JUICE. I THINK WITH THE RIGHT WEIGHT OF CAR, YOU COULD RUN A MID 6.5. MY CAR HAS INTEREIOR GUTTED AND ONLY A GLASS HOOD AND LEXAN W/SHIELD. THE WEIGHT IS A BIG FACTOR.:cheers: