I think I know what this is. Do you? I believe this is a manufactured performance part for th first gen rx7.(not homemade) If you think you know don't spoil the fun. Check out my profile page for My answer. Post if you got it right or disagree.
john

 

is it for a 4 barrle carb or a stock nikki . I have never seen one of those. I did look on the net, and can't find nothing about it.

 

That's an LS1 out of a 99 Camaro

 

Thats a verry rare Super Power Intake Velocity Ion Charger - see the air comes into the carb right, then it goes down into the manifold, then into the engine.
But with this 'Super Power Intake Velocity Ion Charger' The air goes into the carb right, then like Woah! 'Super Intake Velocity Ion Charger!' and the power's on! Then the Fuel/Air Ion's are like "Yeah! Let's Burn Some ****!" Then The Rotors are like, Yumm and Go Spinning away at like 65 em pee haych's! And you're, well, Way Too Fast and Way Too Furious! (I just coined the next movie title)

Put that back on, like Woah!

 

the answer is simple.....a flux capacitor!

 

but it needs 1.21 gigawatts. kinda like this does...

 

Looks like the Mani is from a 4 port 13B. Someone has done some serious porting to that thing. The throttle body spacer looks like something for a big engine (V8)
Either that or a Hitachi with some sort of forced induction system.
Just my guess.

 

looks KETTLRIGGED if you ask me!!!!!!!!!

 

I need one.... is it strait through or is there some shape to the inside? I'm ok with modding the hood to fit, and longer studs. What other mods are needed? I only need the vac advance and brake booster vac ports.

Edit: I see some intake porting, needs to be done.

anyone think its worth a try? or just don't mess with it?

 

Is it a Jackle?!?
It's a jackle!!!

 

here is the article that came from rotary review magazine early 80's. I hope they will be good enough scans for you to read. Keep in mind that no one has been able to verify that this is the plenum chamber that the article refers too yet
john