[BVR421]

On the dynomajig we could see actual gains from shaped spacers and bigger carb. The HP gains were a joke cost wise, but thats not where you want to look for benefits. We could see a much smoother fuel curve thru the pull with a shaped spacer but they only seem to have a beneficial effect when air velocity is sky high? Or was it when the MASS of air/fuel charge became dense enough to resist the vacuum in the port? I dont think my 482 cared one way or the other with a 1050 cfm carb. The shaped spacer really seemed to stand out under the extensively modified early 8896 1140cfm Im not real sharp on this stuff but it was easy to see on the dyno readouts.
The Victor had all the tricks to herd air around.
I think when you get so big with a single carb the air/fuel charge mass resists the vacuum of the port and would rather lay down on the turtle. A little bit like trying to divert my large mass from the fridge to the workshop. Its easier for me to stop at the fridge but thats not where I need to be. Its my impression thats where a shaped spacer shines, getting the now heavy charge moving off in the right direction right out of the throttle bores.
Doesnt necessarily translate to bigger HP number but better brake specific numbers indicating more fuel being burned more completely.
This is all somewhat static testing, put the car on the track there may be effects not obvious on the dyno.
Likewise, what is it you want the spacer to do? Increase plenum volume? Promote directionallity?
I dont see how you can make anything useful of other peoples spacer deals unless you just like taking a poll or promoting discussion (8-)