Two different intake runner lengths

[Alan_RHIT]

I was considering running a design with two sets of different runner lengths. I was thinking about controlling the flow from the long tubes to the short tubes with a valve of some sort. Would this violate this rule?

B8.6.2 Any device that has the ability to throttle the engine downstream of the restrictor is prohibited.

I mean it wouldn't really be for throttling more for flow direction...

Any more current comments?

[Alan_RHIT]

I was considering running a design with two sets of different runner lengths. I was thinking about controlling the flow from the long tubes to the short tubes with a valve of some sort. Would this violate this rule?

B8.6.2 Any device that has the ability to throttle the engine downstream of the restrictor is prohibited.

I mean it wouldn't really be for throttling more for flow direction...

Any more current comments?

[PatClarke]

Alan,
For a difinative answer to this question, you need to submit it to the FSAE Rules Committee.

Nothing said on this site has anything to do with Rules Committee decisions.

Cheers

Pat

[VFR750R]

Having valves in the intake stream won't violate the rules if both intake runners can't be closed at the same time. Otherwise it can't 'throttle'. So if you are planning on using two valves where a combination of the two may cause throttling, the judges will want to see a mechanical linkage connecting them that prevents them both from being closed at the same time. If they both only block 50% of each runner at a time, that wouldn't be considered throttling.

I agree, for a definitive answer, you will need to submit a query with the rules committee regarding your design.

[Yurik]

It doesn't violate rules, we have done it here at KU on our 2010 car that we used last year.

[Charlie]

The device cannot throttle the engine. It's a pretty straightforward rule. Design your intake so that it is impossible for the runner valve the throttle the engine, and you will be fine. There are several ways to accomplish this, the simplest is a 'flapper' style valve.