I HAVE A D16Z6 AND WHEN THE VTECH HITS AT 55OO RPM MY CAR JERKS A LITLLE AND GLIDES SMOOTHLEY FOWARD I GUESS SOME ENGINES WORK DIFFERENT THAN OTHERS ALL I GOT IS A SPOON INTAKE AND GREDDY EXHAUST. AND A PORT AND POLISH HEAD. WITH A OVER BORE AND CONVERTED TO A 1.8 LITER. BUT WHEN THE ENGINE WAS STOCK IT GOT UP AND MOVED NOT MUCH BUT YOU COULD TELL WHEN VTECH SET IN