Robert -

Some Chrysler-provided poop I have says that three Weber carburetors (48 IDA) will "improve engine output nicely" compared to a Hyper Pack inlet manifold and carburetor on the slant six. The sticker is that a hand fabricated inlet manifold would be required (one cylinder per Weber throttle bore).

A far less expensive way to go would be to modify a standard intake manifold to accept a four-barrel carburetor that was used on '65 and later high performance 273's, that carburetor being a Carter 3854-S.

If you're interested going that route, Chrysler says:

1. Replace the metering rods with No. 16-177 rods (.067 - .065 - .055" dia.)

2. Replace the throttle side seccondary jets with No. 120-181 jets. (.049" dia.)

3. Replace the choke side secondary jets No. 120-226 jets. (.065" dia')

4. Replace the primary venturi clusters with cluster No.448-264S.

I have not tried converting a stock manifold to accommodate a four barrel but it has been done and it shouldn't be too tough. Converting for a two-barrel is a snap, but rigging for a four barrel would be a little more involved. You'll have to make a 1/4" steel plate shaped like the gasket for the carburetor and weld it (or in my case get a REAL welder to weld it) to the manifold. Just be careful to center the four barrel bores on the standard plenum chamber.

Let us know what you decide to do and how it works!

Jim