I'm talking about the heat loss on the spacer, where is the heat going? To my mind it's going directly into the engine. Which usually, from a power standpoint, isn't a good idea. Edit; tho it can be good for efficiency. It's been a long time since I've looked into carbed systems so don't remember what happens with such a large plenum, how it affects distribution, power, idle, etc. I'm just wondering if you could explain it. If you can explain it, then you have researched it. If it did what you thought it would, kudos. I think it looks alright, but if it does nothing for power or efficiency, in my books it's usefulness is over.
I hope you don't take what I'm saying as dising you, because I'm not. I think it's great that you're trying out new ideas.
Keep it up,
Richard