Advanced Engineering Tech - air turbulance at entry ??

What I'm interested in is "picking up" air flow at the mouth of the throttle body. AKA...a bell mouth....

Does anyone have data to squash or back up claims in this area ??

Any aerodynamacists in the house ?? Laminar air flow/boundary layer ect.....

You see them all the time in the dyno room or hanging on the front of a FI setup but.....never under the hood (N/A).

I'm willing to "build" a "air bridge" that will encompass the bell mouth entirely (FYI, I'm speed density). Just not sure if theres anything to gain in that enviroment (closed in by the tube).

And with the "tube/air bridge" becoming larger towards the throttle body my concern is the Bernulli principle. The whole pressure/ velosity (inversly proportional) and divergent / covergent ducting theroies.


Any data or theories or opinions are welcome.....Thanks.....

Biggest throttle body that will have the opening large enough to to have zero manifold vacuum at wide open and and then a plenum large enough to kill any harmonics or the turbulent air you talk about :) As far as picking up air flow... I would say your better off looking in the manifold for it and making sure the TB isn't the restriction. My thing is as long as the TB has smooth transfer into the manifold,to keep the air flow as smooth as possible.

I agree but I'm some what restricted by the windshield cowl. Fast 102 w/NW 102 TB.

I'm sending the H/I/TB to my head guy to flow, I want to get a base line or at least understand what and where my limitations are. I'm already aware that the manifold is down on "total" CFM (as compared to the heads). He will flow all three seperate then flow them is different configurations (H/I, I/TB, H/I/TB).

Just from numbers I've picked (vendor info) up on the manifold, it looks like its about 30-40 cfm down at WOT. So....I'm no "smart guy" but I would guess if I had a manometer reading I'd be seeing some vacumm in the manifold.

I understand I'm limited by the manifold design...just trying to make it "easier" on the manifold to keep up with the heads. Sometimes its the small detail that are the eye openers with a given combo.

The things that I can't account for are the pumping/ cylinder pulse/ valve events. Thats the things the flow table can't duplicate.

Thanks......

Right since you cant duplicate the harmonics in airflow your thinking right. What heads, cubic inches, and rpm are you turning? That fast manifold has a lot of plenum area, and a 102 throttle body is fairly large. I'm sure you still have a MAP sensor in your car so why dont you get someone with something that reads live data. Take it out and read what your MAP says at WOT. With the engine off it will read atmospheric (14.7) so at WOT it should read that too, if its less then you have a restriction somewhere in your intake side of things