Advice please : new look of my PMO Carbs

[Xavier PJB]

Dear members, My engine runs on PMO carb (see picture), which are greats. However the way they look with the air filter + rainshield is not very racy. I am aware the "stock" air-filters and rainshields are doing their job.

I did open a topic already on the tea

I like very much the 911R/906 rainshied, and I would need special airfilter to be put under. I am also fan of the ITG cylindric air filter to be put on each venturis.

Any idea ? Advice ?

Thanks.

[gsjohnson]

How 'bout this?

[Xavier PJB]

How 'bout this?

I thought about this, i like this very much but I had several divergent opinion about from members. Mainly on filtration efficiency and air flow performance . Your view ?

[Bullethead]

Either of these types work fine at actually keeping grit outta your engine. Available from most of the usual sources.

[chris_seven]

I have always believed that 'best practice' is to allow a minimum of 30mm clearance between the end of an air horn and any barrier to airflow.

It is designed to allow smooth and even entry of air at high velocities into the intake tract with the flow stream adhering to the pipe walls.

I think pugging the end with a 'Tea Strainer' of fitting a close fitting sockgives less than optimum results.

[Fishcop]

I have always believed that 'best practice' is to allow a minimum of 30mm clearance between the end of an air horn and any barrier to airflow.

It is designed to allow smooth and even entry of air at high velocities into the intake tract with the flow stream adhering to the pipe walls.

I think pugging the end with a 'Tea Strainer' of fitting a close fitting sockgives less than optimum results.

I agree. I'll put on my Nerd hat... I build and fly electric RC "jets" which use very powerful brushless motors and Lipo batteries to power an impellor inside a duct. The opening of the duct has a bell-mouth just like the weber carburettors. A key component of optimising airflow is getting the bell right and the wrong shape or an impediment to the bell-mouth alters the airflow hugely. I can only imagine that a strainer or anything interupting air around the bell-mouth will be a disadvantage.

[gsjohnson]

I ran this setup without the strainers, but with the filters on top of the velocity stack on my 289 Ford with 48 IDA Webers with no ill-effects.

[Xavier PJB]

Well, again there are controversal on this. Any powerbench references on the various air filtering for carbs ?

Velocity stack vs single velocity filter vs one filter for all ?


Cheers
Xavier

[C.Plavan]

Sub'd. I want to know also.

[uai]

chris: There is a scientific publication on this and mainly regarding stack design of the Kraftfahrzeuginstitut University Stuttgart floating around the net - I just don't find it at the moment.
However it focusses on the trumpets not - filtration. The interesting thing was that length and angle of the trumpet are less influential than the radius of the trumpets.
A larger radius with minimum 90° (better more than 90°) flows better than having modulation in length and angle of the trumpet.

And for all airfilter maniacs performance-car-air-filter-test/

[edit] i found it - it was in ATZ but is too large for upload but here a link [/edit]