Dual quad manifold

I have the Offenhauser, D66, and Edelbrock street tunnel ram.
As mentioned, Weiand has a tunnel ram and then there is the $2500 STR-12 (which consistantly goes for around this price everytime I have seen them for the past five years).

I don't like the way the Offenhauser's runner's look like (flow with a huge bend in the runner), the D66 are shaped better (but no air gap), & the Street tunnel ram has been made to perform without any loss of torque in the Hotrod magazine and performance book.

I bought a set of (2) 400cfm carter's, two holley 390 vacuum carbs, and two holley 450's that i plan on trying out on my small block build-on a dyno (and sharing with everyone if people are interested). I also am going to try the Edelbrock air gap and the chinese imitation (came with a motor purchase) to see what work's best.

Most of the time, I think you can get as good, if not better perrormance from a well tuned four barrel (check out S.A.M.'s latest chevy dyno wonder in the mag's), but engineer David Vizard has over three books with references to multi carb induction.

How to build horsepower (Parts 1 & 2- two books), a different revamp of volume one, and chevy small block and big block build up books that utilize multi carb setup's. When he refer's to the more exotic setup's with SU, Weber, Predator, carb's, he had a lot of praise for the FULL-RANGE-performance of one carb-per-cylinder. He also has a how- to -port your own heads book out as well.

Between the port book and the revamped how-to horsepower book he gives stats on a chevy 355 that his student built. This single four barrel motor idled at either 900 or 650rpm (can't remember/am at work), ran up to 8000rpm, is quoted as making 584hp, had a wood spacer, and 10 to 1 compression.

So I think dual quad's is usually stylish preference vice performance advantage. The engine master's motors usually run dual quad's-but are not street motors, and usually are often big block engines.
What the other guy said about experiencing smooth idle and smooth operation through out the RPM band while using dual quad's is what Vizard's tests demonstrated with the multi carb setup. (which is why I wanna try it)

Many of the experienced people here have setp up their COMBINATIONS to run (idle, smooth op thru out RPM band, top end) very well with just one four barrel carberator.