I have a speed density Stealth Ram with a 730 ecm that I made a crude air intake for. I used the stock TPI duct from a MAF car, the air box and lid from same, and a short length of PVC to bridge the gap where the maf was. It's ugly as sin, but filters the air and brings a cold air charge. The question is, my engine idles ~48Kpa, but on level ground or only slight incline it is always between 40 and 46Kpa. Is this common, or could my air intake be a restriction? I hardly ever see over 75Kpa.

 

Can you remove the cold air kit duct temporarily and do a WOT datalog to see what the resulting MAP read is?