Air filter position to butterfly valve

[Meek_racing]

I might be a numpty asking this, but....

If I were to re-design an induction system, does it matter if the air filter is before or after the butterfly valve? If there is a big enough chamber after the filter, will it be the same as per standard airbox? This is non ITB setup btw.

Cheers

Mike

 

[Sam@NP]

You will want the butterfly after the filter, I can honestly say I have never seen a filter after the throttle butterfly in my life so there must be a reason for it. Wouldn't mind knowing the answer why though I think it will be due to air pressures.

 

[steviet]

I doubt you'd want the filter after the butterfly.. I think that after the butterfly, the ECU is looking at airflow/density and adding fuel to match, so to mess around with the air after this point wouldnt do things much good.

 

[Cr33do]

Haha. I thought about this once but concluded that you would probably gunk up the throttle body over time. Not sure how you would package a filter inside a plenum suitable for a clio either. I think the std or V6 boxes are upto the job anyway, it's the plenum that could be improved upon.

Trouble with designing an inlet from scratch is all the other considerations such as runner length/pulse tuning etc. I reckon we could design something that might look quite good but may not guarantee improved results. Unless we copy that carbon box that TdF had on the s2000 engine. Nom!

 

[Meek_racing]

The air purity would be the same regardles or filter position. I guess the only problem would be the butterfly getting gunked up, I was thinking of piping directly from the fog light.

In regards to air flow, if the chamber just after the filter is large enough, would this disturb air flow or air pressure? In theory it's the same route the air would have to take but opposite way around... Yup Nick, basing it on the TDF one but also the ITB setup Fred has on one of his customer cars. Rather than allow the air to move in freely through the lower grill it will have a small lower chamber with the throttle butterfly to the right side.

Will put some sketches up after work.