THE 2.3 IMPULSE ENG IF IT IS IN GOOD SHAPE IT WILL PASS THE SMAG TEST WITH UT AN AIR PUMP UNLESS THE INSPECTOR IS REALLY SHARP AND MISSES SEEING THE AIR PUMP, AS LONG AS YOUR CAT CONVERTOR IS IN GOOD SHAPE THEY WILL PASS THE MOST STRINGENT TESTS AS FAR AS THE STATE TESTS GO , I HAVE AN 89 TROOPER WITH 255.000 MILES ON IT AND JUST REMOVED THE ORIGNAL DUAL BED CATALYST ,NOT ILLEAGLE I REPLACED IT WITH A 3 WAY CAT FROM THE LATER MODEL TROOPER AND DISSABLED THE AIR PUMP IT JUST PASSED THE GA INSP, WITH IDOL AND CRUISE SPECS OF 0.010 % CO, AND NOX WAS 0.001 PT PER MILL, HC WAS 15 PTS PER MIL AT CRUISE , THIS TYPE OF CAT IS LIT OFF BY THE AIR IN THE EX AS IT LEAVES THE ENG WITHOUT HAVING TO HAVE AN AUXILLERY AIR INPUT , THE CARBED ENG IN THE IMPULSE FORM IS 100 HP INSTEAD OF THE ORIG 90 WHER IN THE IMP IT IS 110 WITH THE EFI, THE ENG WILL FIT AND WORK FINE IN THE TRUCK, USING ALL THE MANIFOLDING AND THE DIST AND CARB FROM THE ORIG, 2.3 ENG YOU WILL NOTICE A GOOD BIT MORE PWR,YOU WILL NEED THE ENG MTS OIL PAN, AND ADAPTER PLATE ON THE REAR , AND MAYBE THE OIL FILTER ADAPTER SOME OF THOSE CARS CAME WITH AN AUX OIL COOLER ,USE THE TRUCK FLYWHEEL CLUTCH AND PRESSURE PLATE ASSY , YOU MAY ALSO WANT TO CHANGE THE LOWER WTR PUMP PICKUP PIPE THAT BOLTS TO THE BLOCK SOME OF THEM CAME OUT AT THE WRONG ANGLE BECAUSE OF THE WAY THE RAD IS INSTALLED IN THE IMP , JERRY