Guys..... something else to consider. Edelbrock is now selling a "plenum manifold" that can be adopted to various GM engines. In my case, I purchased their "mid-rise" plenum, which consisted of the base and upper plenum. (The base was designed to bolt to an existing "two x four-barrel" manifold. I machined 1" thick spacers that I placed between the manifold and the Edelbrock base, and then bolted on the upper plenum. The volume of the plenum was a good match for my engine displacement, and permitted use of either stock or aftermarket GM throttle bodies. I now need to plumb the "cold side" between the intercoolers and the throttle body. (All this permitted me to get away from my older sheet metal plenum, which I thought was ugly.) Pics attached of the new set-up. I've been both a Blue Oval and Bow-Tie fan, and you really can't beat a small block Chev for the light weight of the Mirage, and for the engine output--either NA or turbocharged....(!)

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