i would toss the velocity stacks in there while ya can. they will help the air make a smoother transition down the tubes. the straightness creates a ram effect, not the velocity stacks. the velocity stacks will help alot considering you will have a sharp 90 degree angle left upon welding it together, with no way of even getting a die grinder in there to smooth the transition. cheapest i've found the horns though would set ya back about $200 for 6 though. unless you have the ability to cnc your own, lol.

ya, in reference to the old carb style manifolds. there is one huge thing you need to consider. they had to move fuel also! designs had to be tested alot more to keep the fuel atomized till it hit the valve. then the mixture swirls around the valve pocket once the valve slams shut.
some of the best manifolds for old motors was things like the kinsler and other one off stack injection manifolds (very similar to what mrc is doing). the length and dia of the stacks will taylor your torque peaks. single plane was designed for a higher hp curve due to a larger plenum area, with dual planes designed for better torque due to a stronger intake signal reaching the carb.
all the single and dual planes went the way of the wind with direct port injection. with the fuel injected right before the valve pocket, all you had to worry about was airflow. plenum volume is far less touchy with fuel injection, and really you want the intake runners to feel they are not even enclosed, so the larger the intake plenum the better. for those who disagree, do your research.
btw, i have seen the similar manifolds on the sbc, can't remember where or what car it was in, but ya, pretty cool chit.
good luck guys, can't wait to see the final product!

 

nice work guys.

 

Very Nice MRC.

 

So whatever happened to this project?

 

Still in the works..The guy working on it is also in the middle of several other projects for us.