Quote:
Originally Posted by GregWeld
Good question Jody -- I have no clue!
My throttle bodies are 2"... and based on the IDA Weber "platform"....
I don't know what the flow rate is - if you stacked all 8 and did a WOT -- but I'm thinking it's way more air than my motor will ever need!! 
In fact - I've thought about that many times - thinking about the blades on a 850 CFM Holley -- and then comparing that to the "area" of 8 x 2" holes... I'm thinking these manifolds have to be capable of 1200 CFM plus? |
well, total cfm doesn't mean a lot when you're speaking of individual runner setups. There is no "borrowing" for a cylinder like there is in a common plenum setup, the max airflow for a port is whatever that port/blade can flow.
I remember with my Hilborn setup, it used 2 3/16" blades which seem huge; flowed like 280 cfm per port , so like 2200 cfm total.................. problem was my heads were good for 312 cfm per port (intake), so I actually was pulling 2-3 inches of vacuum at wot, showing the flow restriction.
With higher hp IR setup you need to make sure they can flow enough to support your power level. Many of the smaller setups will support maybe 500 hp or so; not a problem with most engines but something to consider with a stronger build or larger engine.
Jody