So having said that, the GenVI I have was done in late 99 by the casting number so it probably came out of a 2000 truck of some sort. It has something other than peanut size ports which I assume are the standard port size for a Vortec. What is the difference between the standard oval port intake and the Vortech oval port intake? I will be using a carburetor so intakes for a Vortec seem to be a little limited. Not looking for anymore than 5500rpm so those ports look like they will do a good job up to the 5000rpm range for me, not looking for a cam that goes much above 5200 anyway.