Let me better explain, as you know the intakes were designed for their respective heads, everything else being equal, the explorer may feel sluggish on the bottom with e7's like you experienced in the vert. There are ways to make them work or do like you did and make the intended stuff (stock intake) work!Just in case you were replying to my response, my old 93' always had E7 heads. It was the intake manifold that was changed. I believe the Gt40 style intake manifold was made to work with the higher flowing gt40 heads, hence the worse low-end rpm range performance with the stock/more restrictive E7's. The E7 powerband seems to be more compatible with the stock HO intake power band. It just felt that it was a bit of a mismatched combo on my old stock headed 93 gt. That's why I kept the stock HO intake setup on my 91'. I still had the stock lower intake in my shed from my old 93' and decided to have my dad port it (he has steady hands). Since I had to remove the intake manifold to fix the leaky lower intake gasket and had that lower intake in the shed, I had decided to take advantage of the situation. All of the runners in the lower intake have been worked on, but the front two runners (1 and 5) were worked on the most heavily. I find the power band of this manifold to be more enjoyable than the Explorer one in my aod gt vert.