Direct to head throttle bodies - butterfly position

[CitroenFreak]

When having throttle plate just at the head entry(lets say 1 inch away) is it better to have it positioned vertically instead of horizontally?

As the throttle will cut the flow in upped and lower part if horizontally, where if positioned vertically it cuts flow on left and right part, just like the valves are positioned.

What's Your oppinion?

Cheers

Ziga

 

[patprimmer]

I don't think it will make much difference at WOT or very low throttle opening.

At part throttle it will favour one valve over the other and therefore might introduce a bit of swirl and shear between the air streams which just might improve combustion speed and thermodynamic efficiency. Notice I say MIGHT not will.

Testing on a flow bench will give a better idea of probable outcome.

Regards

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[CitroenFreak]

Yes, I will give it to someone with flowbench to test it up, but I just wanted to ask first if anyone on there has done it before.

Cheers

Ziga

 

[Fabrico]

Operational convenience is probably a more important factor. Also it would depend on where the injector sits. My guess would be that this, and more, is why most OEM setups are sideways.