"........... ''Dual quads w/tunnel ram'' is not the optimum street use set up either. Sure it can be done, but there are better more street friendly systems out there............" pro70z28 is absolutely correct. Chances are your motors will make more power and be a lot more fun to drive with a well matched single 4 bbl and appropriate manifold.

Tunnel ram manifolds were/are basically a race only piece designed to operate in a narrow high RPM range and tend to fall on their face when operated outside that range . Low RPM throttle response, idle quality and torque are also generally adversely affected when operated outside the RPM range these manifolds are designed for. Lets face it the only reason the only reason to run on of these manifolds on the street is either the "WOW FACTOR" or you have a VERY serious street racer (were talking an almost all out race engine with high compression, lots of cam, head work, a stick or very high stall converter, and deep gears).

That being said this is what I've found that may help you live with these on the street.

Manifold: Several years ago when the tunnel rams started showing up on the street (anybody remember the 80's and the start of PRO-Street?) some of the manufactures started making street tunnel rams. The basic design change was that the runners were smaller than the race pieces which helped with throttle response and helped keep the fuel suspended in the air stream. If you have a choice go with the manifold with the smallest runners available.

Carbs: Go conservative and use a carb with vacuum secondaries (or an AFB type carb with a secondary air valve). The 450's you have should be fine as long as their vacuum secondary. The secondarys will only open on demand and only as far as required (chances are with your stock 350 they will never fully open). The smaller the primaries are the better the throttle response will be.

Iginition: You will need the best you can find. Something like an MSD to help keep the plugs from fouling at low RPM might be a good investment.

Gears: Go with as deep of rear end ratio as you can live with. This will help make up for a lack of bottom end torque and put the engine RPM range closer to where it needs to be for these manifolds to work and will help make up for a lack of bottom end torque. If you running an automatic, start looking for a hi-stall converter. It will help pulling away from a stop light without embarrassing yourself.

Plan on doing A LOT of tunning to get the most out of these manifolds on the street. Chances due to a poor low RPM vacume signal you will need to play with power valves (or step rod springs if dealing with an AFB), jetting, secondary opening rates, and timing to get it to the point where it is livable.

Good luck to both of you.