Air filter box design

[mjb67]

While I was fiddling with the fuel lines the other day I noticed that the air filter box is designed to cover part of the carb intake elbows. Instead of oval holes revealing the elbow openings, there are sort of squared-off ear shapes covering about half of the opening.

I don't really know anything about intake design, but I thought you were supposed to avoid obstructions upstream of the throttle plates.

Does anyone have an explanation for why the Stag is designed this way?

[Stagsongas]

Matthew,

I've noticed that, I think it was intended to generate vortices (turbulence) in the incoming air for better fuel mixing.

Regards

Steve

[mjb67]

Mmm, that sounds plausible.

[flying farmer]

I believe it was done to even up the flow across the width of the carb. The tight bend on the intake was biasing the flow to one side and this peculiar arrangement is intended to correct it.

I have the intake from a very early engine and it has full diameter holes into the aluminium elbows, but later type sections with the obstructions are bolted over the top of the holes. I have no idea if this was a factory job, or an owner fitment, but I can't imagine an owner wanting to obstruct his carbs airflow, so wonder if it was a factory job. The engine is a service replacement unit, LF8ESS

Neil

[Guest]

I noticed the same thing a few years back.I decided to cut the pieces out and make it completely open.Certainly has'nt made any difference to running or performance.I however like the idea of no restrictions to the inlet airflow
anthony

[StagnJag]

Don't forget that the actual cross section of the air intake is a lot smaller than the visible cross section at the air filter inlet as it is cutting through the elbow at a shallow angle. I guess they were trying to even up the areas a bit.