Originally Posted by vinniekq2
when I used 2 x 4 bbl on my street car, I used 2 x 750s. For some reason people think that you divide 1 four bbl in 1/2 and use 2 small 4 bbls,not true.You would use 2 carbs the same as if you used 1 carb on a single carb manifold( approximately) Tunnel rams come with different plenum sizes same as single plane intakes. If you buy a "cheap" tunnel ram,expect the same performance as buying a cheap single four BBl with an extra carb to add to the confusion.
"cheap" has nothing to do with it, it just needs to be properly sized. A used swap meet edelbrock tunnel ram is one of the best tunnel rams for a street car.
Look for long runners with a relatively narrow cross section for a good street tunnel ram (it'll help mid range torque). Short runners with a wider taper are for top end power. A good example of this is comparing a LT1 intake to a TPI intake, the TPI intake produces much higher low end torque and the LT1 intake produces higher peak hp. This is also the primary reason for a dual plane intake- runner length and packaging.