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sansnombre

Intake Flow Simulation - ADDING INTAKE VELOCITY STACK

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Zephyr
Intriguing to say the least. Definitely interested in the results of your analysis. The exhaust port mod has my attention. I could envision a much more economical airbox than what I'm seeing here. Looking forward to future posts and the tremendous discussions that should take place through this endeavor!

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peteinpa
I'll be watching also.

Got new red 2015 FZ-07 on 7/22/16!
Black 2006 Honda ST1300 53K miles.

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norcal616
I have always wondered if cutting the long intake crazy straw tubes inside the stock airbox shorter or as close to the end of the airbox as possible will help you achieve that nice mid range to top end pull with the MWR filter... I have a stock airbox to donate if you need one to offer up to the gods of HP/TQ...you will still need a PCV to correct the fueling and ignition once you decide on what you want...i personally think the stock airbox is fine just needs diffrent intake tubes and I see why Hordpower went with his idea, it's impossible to get inside the stock airbox without destroying it to modify/play around with to do data testing...

2015 fz-07- Hordpower Edition...2015 fj-09- 120whp- Graves Exhaust w/Woolich Race Kit- tuned by 2WDW
 

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sansnombre
@norcal616
I actually purchased a second airbox for this analysis. I get to still ride and have this box sitting next to me on the floor, so I can take measurements and what-not. Thanks for the offer, though.
 
I'm not sure if you can see it in these pictures, but the exhaust runners come up to and terminate near the very center of the filter element. So half of the element is *behind* the intake of the exhaust ports. So the flow has to route back and around to get out.
 
Also, notice the vortices on picture number 2, in the blue sections. This is because we're shooting all of our flow out the bottom portion of the filter and it's hitting walls and spinning around. I think there will be a big change with the interior of the snorkel removed. Looking forward to that analysis as that's what I originally did to my bike, until I dropped the MWR set in.
 
If I'm not mistaken, Hord removed the filtering element and snorkel completely and left everything else as stock to get that run you see above. Basically a big square hole in the top - not too efficient, but look at the change. Huge! That kind of torque increase at 5k is something you'll notice for sure. His comments were that he believed that the filter was blocking the intakes of the exhaust ports, and clearly they are. We can't really do anything about that and still use the standard filter location . . . unless we pull back the intakes of the exhaust ports 2" or so. I think there might be some magic there - in addition to opening up the intakes (not being so close to the filter and walls) it will remove some of the twists in the right-hand side tract. It's very twisty. So if we reduce them, they don't have to be pushed to the side to avoid the filter and can be straight.
 
3D printed liquid silicone is quite expensive, and it wouldn't make sense to have an injection mold created, so what I'll probably have to do is cut these down and then just do a 3D print of a nicely-shaped intake flair and glue them on. At least that's what I'm thinking now. With being able to design it and print it at home, I should be able to get one that fits well.
 
All talk at the moment, going to take weeks to find the time to do this, but I appreciate your interest.
 
Until then, I have a new MWR filter and cover to try out . . .
 
 
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stickshift
Very interesting.
 
I too saw Hord's chart and wondered what could be done to improve the standard airbox and filter arrangement.
 
I'll be keenly watching this!

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sansnombre
Bump - new information added . . .

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peteinpa
Next take off the top leaving just the filter.
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Got new red 2015 FZ-07 on 7/22/16!
Black 2006 Honda ST1300 53K miles.

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Mr.Puss
  [attachment id=2474" thumbnail="1]
 
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Crush your enemies. See them driven before you. Hear the lamentations of their women.

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sansnombre
Bump - new information posted: removal of full snorkel assembly (inside and out) and same with filter removed as well.

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peteinpa
Just to clarify, on the last setup you removed the whole rubber part and the plastic part? That's how I'm running now with the stock air filter and flash.

Got new red 2015 FZ-07 on 7/22/16!
Black 2006 Honda ST1300 53K miles.

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sansnombre
Yes. If you look carefully you can see the hints of the parts inside the unit. On the one before the last, you can see the filter in there. On the very last one, just the cover is installed - the external snorkel and the internal oval "tubing" has been removed.
 
From what I've seen this far, that's what you should be running. It makes the biggest difference in my analysis and also matches what I've been told by 2WDW.
 
The only thing that will change this is an external filter solution that opens up the flow corridors in front of the intakes to the exhaust ducts. I'm working on a hard solution now, and I think it's quite doable.
 
Should have something to show in two weeks or so, and it should yield a solution very similar to what Hords dyno curve above shows. Wheelie central I'm thinking . . .
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rhb
You did it, a lot of work to satisfy your curiosity, but interesting to see the graphics, what we do for academic knowledge. :)
 
I would only mention for those trying to see big differences from one scenario to another, that probably between an MRW filter, DNA filter with or without cover (should we see those data someday), that the overall measurable performance differences are within a fraction of a percentage point. not much.(only my guess based on velocity stack design differences) And as Sansnombre mentioned this is only benchmarking differences in scenarios, not indicating performance values of the system, a way of comparing away from the real world, only dyno tuning yields measurable system performance, and even then, on any given day so many variables come into play, its hard to pinpoint what is contributing to what. the dyno tuners experience over thousands of dyno runs is probably more important.
but none the less nice work so we can visualize what goes on in our airboxes.

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sansnombre
I haven't posted actual numbers yet (I'm measuring flow rate on all scenarios for comparison) but you're right - most of them are very, very close and the differences are negligible. There are two major differences though - removing the entire airbox lid/snorkel/filter (best flow) and the removal of the entire snorkel (inside and out), which yields the second best setup. Both of those had large step changes in perf from the bulk of the scenarios thus far.
 
There are quite a few conclusions to be drawn from all of this, but I'm waiting until all the scenarios are completed before posting them as well as the actual data.
 
As @rhb points out, it's important to understand that the state of the intake flow (similar to overall engine performance) is a long chain of serial orifices and obstacles. If we focus on one of those links in the chain and optimize it, great, we can reduce *that sections* perf hit by ~25% and that's a big deal . . . in *that section* of the chain. OVERALL we've still barely done anything to increase performance. The tuners (those with lots of dyno time with this bike and all the variations) almost all point to the fact that there really is no measurable difference between the filters, filter covers, radiused vs sharp edge, etc. There is one exception I know about and that has to do with an interesting phenomena with one header in particular, but other than that, these changes are generally idealized increases, but not really impacting. For instance, there's no question that one gets better flow particulars with a radiused edge vs. a sharp edge, but the impact on perf is not going to be seen. It's change is equivalent to noise in the system - temp of the oil, ambient temps, gas quality, temp of the engine, etc.
 
Again, some major exceptions, and that's what this is about: what matters, what doesn't. Within the next several weeks I hope to be able to finalize and post those results.
 
Thanks for the input.
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hordboy
This is interesting stuff, but static flow models are only one small part of the equation as I'm sure you know. The tuning of the intact tract has a far bigger impact. Runner length, volume, etc. The test I did removing the filter and snorkel assembly completely, proved the stock runner length is ok for midrange, but the volume of the airbox is too small, and the runners are badly shrouded by the filter. I think the solution there is a flat panel filter over the airbox opening, or an "upside down" filter on the outside of the box. Room is limited for that.
 
I did experiment shortening the intake runners and installing proper velocity stacks inside the stock airbox. It gave a decent gain and perhaps warrants further exploration. I did a LOT of testing of various things. OEM style replacement filters just aren't going to give a big gain. This is why my airbox design came into being.
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J.D. Hord
 

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sansnombre
Interesting you should comment on the flat panel filter on the outside . . . one is in transit now for fitment and experiment. Actually, two - one is a beveled one that's a little small, but should be an easy fit. The flat panel one is going to take an adapter but will likely work pretty well.
 
Thanks for the info on the work you've done - your dyno chart with that big midrange gain was the impetus for this analysis and got me pointed in the right direction.
 
For what it's worth, the work here is validating your analysis that the filter location is badly blocking the intakes for the exhaust tracts.

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5tonfan
I need more popcorn and math. Excellent work can't wait to see the flow with altering the runners.

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sansnombre
Bump - posted another section. This one with reduced exhaust tract lengths.

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sansnombre
Bump - MWR tested . . .

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Guest 2wheeler
I pulled my FZ apart and watched the intake as I rev'd pretty aggressively, and you can see a significant vibration settle into this filter at certain engine speeds. It appears transient as you move throughout the rev range, coming and going, but this is not a good thing. It's equivalent to mixing up and churning your flow and has to have a negative effect on the flow when it's vibrating. The interesting thing here is that the vibration magnitude and RPM location is going to be specific to each bike, as it depends upon quite a number of moving and dynamic factors in your engine and exhaust, so it's possible that some bikes won't see this issue and others might. Vibration is complex and there is enough variance in all these factors specific to each bike to have the vibration occur at frequencies that do not induce the vibration in the filter, or only outside an RPM range that is not used and only theoretical. This would explain the differences between the two tuners. Hard to say, but my work shows that it SHOULD increase the flow and therefore power, at least by a little.
I am assuming that you are seeing this vibration with the combo of the MWR filter and MWR lid. For those of us using just the MWR filter and the stock lid with the snorkel completely removed, I wonder whether the vibration would come into play with that combo. Then obviously you would not have the degree of air flow that you would have with the MWR lid which may help the vibration but not provide enough air flow to make a difference performance wise. Plus as you said, there are other variables that may be affecting the vibration too. 
Any thoughts on this?
 

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rhb
Believe the tuner who says intake mods are not the place to look for great HP increases, especially between 2 different "high flow" brands, lid or no lid.
These difference while they may be visible on today's dyno run(vs, tomorrows or another bike etc), are largely academic.
my opinion.
 

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sansnombre
For what it's worth, that's what being shown in my research as well - and actually is the point of all this. Sharp edge vs. radiused, K&N vs. DNA, snorkel out vs. in, etc. MOST are not worth our time or $ if we're looking for HP gains, but there are a few that make a difference. I have to say that I'm surprised that the MWR combo is not showing better on the dyno, as it's pretty well wide open and flows very, very well on the simulations . . .
 
I'll conclude this whole thing after two more rounds of changes. At that point, I'll add numbers and observations.
 
@2wheeler: I don't think it's related to the cover being used or the flow characteristics necessarily. It appears to be just standard engine rumble and vibration that is activating the natural freq of the filter at certain frequencies. It comes and goes as you rev, but, again, it's going to be specific to each bike and tolerances in all the things that make your bike rumble and shake and vibrate. I think it would be an easy fix to have a screen "cage" around it (similar to the stock) that keeps it from doing this, but it's very hard to say if this is what is causing this filter to show differently on different dyno runs and bikes.

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sansnombre
Bump: added intake velocity stack with std and shortened exhaust tracts.

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pineappleunderthesea
I put in the MWR filter and new lid a couple weeks back, and immediately noticed an increase in vibrations at a certain RPM. You get used to it, but does seem to match up with the simulations. Not sure my butt dyno saw any increase in power, but like many mods on this bike, it's the cumulative effect of many things that end up making a noticeable difference.

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sorkyah
Bump: added intake velocity stack with std and shortened exhaust tracts.
What pressures/densities are you running the sims at?  
 

ATGATT... ATTATT, two acronyms I live by.
 

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