Weber 40’s side draft filtration options

[Dionk]

Have been shopping for ideas on what to use as a filter for my Weber 40s.

 

saw this on eBay - anyone else using this push in filters on their standard Weber 40 horns?

[Stevenola]

I would think those would offest the purpose of the trumpet - smooth airflow entering the venturi.  But they sure would look better than all the foam and paper filter sets out there.

[2002Scoob]

OOfff. those are going to be hyper-restrictive, and as Stevenola alludes, disrupt the airflow into the trumpet. 

 

Carbs/throttle bodies, etc, all want a large volume of smooth, still air to pull from if possible with as little restriction as possible. So the best option is a large-volume airbox, with a high-surface-area filter that's as far away from the face of the trumpets as possible. 

 

Tons of options out there. Pancake filters are low-profile, but offer little air-volume, typically don't allow for trumpets or only very short ones, and a small surface area to the filter. There's tons of Foam options, between socks, per-carb options, or large volume filters that encase multiple carbs in one volume. 

 

All the single-throat stainless mesh stuff is for show-only IMO, and will rob you of many, many hamsters- What you show seems like an even worse option IMO. 

Edited March 11, 2020 by 2002Scoob

[Tommy]

 ? If you're scared of the performance after DCOE upgrade those could be used to choke it back to single throat level.

[2002Scoob]

If you're into originality, you can also look for an original Ti style airbox that came on a variety of cars/models, or the Alpina version too.

Those are actually proven to make decent power and be a great option vs. most else that's out there. 

 

Edited March 11, 2020 by 2002Scoob

[KFunk]

I don't know which size I have exactly, but I've got some red angled UNI filters, kind of like these ones:

https://www.bikebandit.com/aftermarket-parts/motorcycle-fuel-and-air/air-filters/uni-2-stage-angle-pod-universal-motorcycle-filter/p/27761?b=24520&CRTP=psc&gclid=CjwKCAjwmKLzBRBeEiwACCVihl19w7qxmlv5B4Bkcc45bUvGTfWJ2eh8dMGHz7VRht4mtG0zMyGlSRoCT60QAvD_BwE

[Dionk]

6 hours ago, 2002Scoob said:

 

If you're into originality,

 

I’m not but have always loved the look of these. Have been told they are a pain to fit.

[Dionk]

8 hours ago, 2002Scoob said:

There's tons of Foam options,

This is my likely approach.

[Dionk]

20 minutes ago, KFunk said:

UNI filters

What size flange did you buy? Would you buy the same size again?

[KFunk]

14 minutes ago, Dionk said:

What size flange did you buy? Would you buy the same size again?

 

I, uh, cannot recall where I placed the order to find the receipt.  Searching my emails and memory, no luck.  May have simply walked into Summit Racing and bought them in person.  I'll see if I can find a part number on them tonight.

Yeah, I'm happy with them for the most part.  Only issue is the stock  base model brake booster in the way.  They'll fit around it, just one pops up a little and looks goofy.  I was hoping the bend would be enough to get around it, but no.  Maybe combined with bent stacks it would look better, but I haven't cared enough to pay for those, and just using the straight ones.

Edited March 11, 2020 by KFunk

[KFunk]

this space for rent (mistaken post)

Edited March 11, 2020 by KFunk

[zinz]

+1 on the UNI filter

 

These are what I've used for many years with great success.  HUGE filter area and the angled bases help clear the standard brake booster, too.

 

https://www.denniskirk.com/uni/two-stage-pod-filter-w-angled-flange-2-1-2-in-i-d-x-6-in-l.p305050.prd/305050.sku

 

Here they are on my engine

 

Edited March 11, 2020 by zinz

[KFunk]

There we go, managed to find the order confirmation in my email, Dennis Kirk is where I bought them:

Two-Stage Pod Filter w/Angled Flange - 2 1/4 in. I.D. x 4 in. L - UP-4229AST Part #: 305044

[Oldtimerfahrer]

I run the stock ti airbox with 45dcoes, I don't pull it off that often, maybe every two years. Is not too fiddly for my taste. Original boots fit over angled trumpets, I have some rubber sleeves on the outsides of the trumpets to ensure no air leaks. Works ok, less intake noise bet that's ok. I want to put it on the dyno to see what the loss is. 

Andrew

[jp5Touring]

I have the Ram Air foam filter. Been pretty happy with them.Uni is a good name but I couldn't get them to stay in place.

Ram Air also offers a aluminum  backing plate if you want that also.