The Definitive 'Pod Filter vs. Open Airbox' thread

[Howley]

OK, there have been so many threads about this, but I've still not got a definitive answer.

Which is better, Pod Filters or an Open Airbox?

[A.duc.H.duc.]

Pods look better everytime.


... and when I say that I'm talking about opening up the frame from a profile view.

[brad black]

open airbox is cheaper, so gets my vote because i'm a tightarse and like having somewhere for my battery to go without too much effort.  pods would be way too much effort for me, even if it does help jetting changes.  because i try to avoid them too.  too much effort.

pods with a box around them may possibly work better, but i'm not convinced of that.  a pod with a good inlet shape might have an advantage, a pod with a bad inlet shape would have a disadvantage.  most people do pods for at least partially visual reasons, so that may have an influence on which is better for you.  visual is not so high on the list for me, as the dents, scratched std mufflers and ventua rack plainly exhibit.  plus there's only one filter to clean with the open lid, but then we're back to effort adn lack of again aren't we.

i think any internet threads with "official" or "definitive" in the title are by nature largely delusional, as the ratio of experienced result to speculation is so low.  but i could be speculating.  well, i am because i haven't tried pods.  see, i've shot my argument down all by myself.  is that self centred or just an inevitable realisation?  serves me right for trying to be a know all.  oh well.

sorry for wrecking your thread howley.

[supertjeduc]

I have Pods on my M900Sie
Pro's  better sound that with airbox
         Less plastic (about 5 lbs)
         More vintage look 
I dyno'd it with K&N /Airbox and after i put the Pod's on and there was 0.5 hp difference

[RB]

I have Pods on my M900Sie
Pro's  better sound that with airbox
         Less plastic (about 5 lbs)
         More vintage look 
I dyno'd it with K&N /Airbox and after i put the Pod's on and there was 0.5 hp difference

in which direction?

[supertjeduc]

Not up 

[jimmygomk3]

Where would one buy said pods (01' 750)? DIY anywhere?

[scooby]

Where would one buy said pods (01' 750)? DIY anywhere?

Chris at www.ca-cycleworks.com has them...

I have some from TPO on my ride; love them! They sound great and clean things up...

[psychochild]

Ok, Ive written about this quite a bit but heres my take on the whole thing:

short answer:  Pods are better, but not through the TPO kit.

Ive run both an open air box and pods and there are a few things that you have to realize about the difference between the two.  Since our bikes don't fire simultaneously, like say a Harley twin, each time one of the cylinders gulps for air, it take in the entire volume of the air box,  by switching to the tiny k&n round filters,  you giving each carb or TB a smaller volume of air to swallow at initial take off.  thereby diminishing low end torque and initial power, which in my opinion is what makes our twins so much fun to drive.  however at higher load and rpms your able to re-fill that smaller volume much faster due to the high surface area of the round filter, yielding more horsepower top end.

With this in mind, I immediately eliminated the TPO kit for two reasons,  one the tiny filter size,  two the uneven flow of air across the two filters.  after some careful measurements I bought the two largest pod filters I could fit under my tank,  to try and maintain that low end power yet keep the high top end advantage of a high flowing filter, not to mention the amazing sound they make.  Ill post up my dyno chart when i get a chance but its a significant improvement over stock with a higher horsepower top end and a steeper curve than just the open air box with a K&N panel filter.  heres a picture of my setup:



my vote goes for custom setup with pods,  and i swear to god when somebody brings up velocity stacks on the tpo kit im going to smack someone.  Not set of velocity stacks with K&N branded filters is worth 200$.  my setup cost under 100 including a dynojet kit and a few extra jets.

[rvictorios]

Ok, Ive written about this quite a bit but heres my take on the whole thing:

short answer:  Pods are better, but not through the TPO kit.

Ive run both an open air box and pods and there are a few things that you have to realize about the difference between the two.  Since our bikes don't fire simultaneously, like say a Harley twin, each time one of the cylinders gulps for air, it take in the entire volume of the air box,  by switching to the tiny k&n round filters,  you giving each carb or TB a smaller volume of air to swallow at initial take off.  thereby diminishing low end torque and initial power, which in my opinion is what makes our twins so much fun to drive.  however at higher load and rpms your able to re-fill that smaller volume much faster due to the high surface area of the round filter, yielding more horsepower top end.

With this in mind, I immediately eliminated the TPO kit for two reasons,  one the tiny filter size,  two the uneven flow of air across the two filters.  after some careful measurements I bought the two largest pod filters I could fit under my tank,  to try and maintain that low end power yet keep the high top end advantage of a high flowing filter, not to mention the amazing sound they make.  Ill post up my dyno chart when i get a chance but its a significant improvement over stock with a higher horsepower top end and a steeper curve than just the open air box with a K&N panel filter.  heres a picture of my setup:



my vote goes for custom setup with pods,  and i swear to god when somebody brings up velocity stacks on the tpo kit im going to smack someone.  Not set of velocity stacks with K&N branded filters is worth 200$.  my setup cost under 100 including a dynojet kit and a few extra jets.

what size filter did you use?

[He Man]

THat doesnt look like theres that much more interal voulme when you compare them to the TPO included pod filters. Although i agree with you 100% those velocity stacks do not make the kit cost such a ridculous amount of money. You can buy velocity stacks in premade sizes for as little was $25 a piece) Its not billet alluminum, but its all the same after you polish the inside with 300grit and hide inside your filters.

I dont want to kill TPO, but i know someone who has a set and im going to ask him to remove his velocity stacks so i can take some measurements.

[MotoCreations]

I've been running no airbox -- no air filters either -- just medium velocity stacks wide open on FCR's for @4+ years.  Admittedly not the ideal situation for most people.  Loud as can be listening to them gulp the fuel while riding.

[psychochild]

Im not 100% sure on what the exact part number is but I believe they are these ones: http://www.knfilters.com/search/product.aspx?Prod=RA-0770

[dlearl476]

I've been running no airbox -- no air filters either -- just medium velocity stacks wide open on FCR's for @4+ years.  Admittedly not the ideal situation for most people.  Loud as can be listening to them gulp the fuel while riding.

When you say "medium" what size do you mean.  AFAIK, they come in 15, 25, 30, 50 and 70mm lengths. (At least they used to.  Apparently, Sudco isn't making them anymore).
I've been contemplating the same, although I'm sure the moment I did I'd hit a friggin dust storm  (which happen all too frequently here in Las Vegas).

I'm in the process of doing some mods, and won't be able to dyno anything probably until I return from a working trip mid-july. But a couple of thoughts occured to me.

Ok, Ive written about this quite a bit but heres my take on the whole thing:

short answer:  Pods are better, but not through the TPO kit.

Ive run both an open air box and pods and there are a few things that you have to realize about the difference between the two.  Since our bikes don't fire simultaneously, like say a Harley twin, each time one of the cylinders gulps for air, it take in the entire volume of the air box,  by switching to the tiny k&n round filters,  you giving each carb or TB a smaller volume of air to swallow at initial take off.  thereby diminishing low end torque and initial power, which in my opinion is what makes our twins so much fun to drive.  however at higher load and rpms your able to re-fill that smaller volume much faster due to the high surface area of the round filter, yielding more horsepower top end.

The internal volume of one cylinder on my m900 is 450cc.  The volume of the stock airbox is much larger than that.  On top of that, opening the box and replacing the top with a K&N, IMO, completely elimates any restrictions and/or harmonic resonance issues/benefits associated with the closed airbox.  At that point, the only limiting factor is the stock velocity stacks/airbox adaptors that most set-ups use. (including yours, if I'm seeing the photo correctly)

With this in mind, I immediately eliminated the TPO kit for two reasons,  one the tiny filter size,  two the uneven flow of air across the two filters.  after some careful measurements I bought the two largest pod filters I could fit under my tank,  to try and maintain that low end power yet keep the high top end advantage of a high flowing filter, not to mention the amazing sound they make.  Ill post up my dyno chart when i get a chance but its a significant improvement over stock with a higher horsepower top end and a steeper curve than just the open air box with a K&N panel filter. 

One of the things air likes to do least is turn corners.  That's why I theorize that SOME KIND of velocity stack is beneficial.

It's also why I feel that any filter that blocks airflow directly into the venturi is,well, blocking air flow.   Especially if it's too close to the opening of the velocity stack.

my vote goes for custom setup with pods

That's why I opted for UNI foam filters rather than K&N ones with a top.


When I get a chance to run the dyno tests with several combinations of pods/stacks I'll post the results.  I'm not holding my breath for any huge gains.  I thinking .5-2 hp like supertjeduc reports are going to be about it.  Like he said, it's more about losing the 5 lbs of plastic.

[greenmonster]

I dyno'd it with K&N /Airbox and after i put the Pod's on and there was 0.5 hp difference

Airbox lid was open?