Since reading the recent post here about filling the Plenum slot in a Blue Thunder intake & a similar article in issue #140 of Y-Block Magazine, which also included a 2nd article on modifications to an ECZ-B intake, both writen by Doug Thrasher, I noticed a variation in the intakes.. The old "B" intake had what I'll call siping or ridges running in the Plenum floor lengthwise towards the runners. The Blue Thunders have a smooth Plenum floor & checking photos of a Mummert intake, it has ridges running crossways in the Plenum. The question being, is there specific reasons for the differences? 


Paul