Lars v's Standard Airbox

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PK001

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Well here it is folks!

A back to back comparisson of the Lars airbox mod and the standard airbox. Dyno run was undertaken on same bike. The difference between the two dyno runs was swapping the airbox and the PCV map was retuned to acheive optimum A/F ratios for the changes. It was noted that aditional fuel had to be added (2-3%) when retuning of the map for the standard airbox to achieve the target AFR of 13.

Results are interesting to say the least.


LarsVsStandardAirbox_zps5d03a411.jpg
 
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Arrow Headers, Leo Vince Slip-on, AIS Blocked, Standard Airbox (Previously LARS Airbox), K&N Filter, Longer Velocity Stacks (Factory Pro), Shaved Secondary Butterflies (CD), Reflashed ECU, PCV

The bike only has 2600km's on it so it is still bedding in/tight
 
T84A said:
Thanks. So other than sounding pretty cool, the airbox mod is pretty insignificant.
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Oooohh thats a sensitive subject :eek: I was curious about how much additional power a cut airbox would infact produce so thought i'd run the test.

The cut box certainly produces a louder induction sound. I'm not sure if anyone has done back to back tests also to compare differences on their bikes, but these were my power outputs.

The main reason i ran the test was to see if it was easier to adjust the A/F ratios in the lower rev range, as i found the AFR was fluctuating with the cutbox and producing varied results. The target AFR of 13 was achieved easier with the stanard box and it produced less variation.
 
PK001 said:
Oooohh thats a sensitive subject :eek: I was curious about how much additional power a cut airbox would infact produce so thought i'd run the test.

The cut box certainly produces a louder induction sound. I'm not sure if anyone has done back to back tests also to compare differences on their bikes, but these were my power outputs.

The main reason i ran the test was to see if it was easier to adjust the A/F ratios in the lower rev range, as i found the AFR was fluctuating with the cutbox and producing varied results. The target AFR of 13 was achieved easier with the stanard box and it produced less variation.
Click to expand...

I'm guessing the added turbulence and lower velocity cancels out the benefits of the increased intake area.
 
PK001 said:
The cut box certainly produces a louder induction sound. I'm not sure if anyone has done back to back tests also to compare differences on their bikes, but these were my power outputs.

The main reason I ran the test was to see if it was easier to adjust the A/F ratios in the lower rev range, as I found the AFR was fluctuating with the cutbox and producing varied results. The target AFR of 13 was achieved easier with the standard box and it produced less variation.
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That sums up my findings. Cut box gives the same power, harder to tune and sounds great. The power increase that most tests gain is they did not fully tune each setup before retesting.

Any new tunes that I help with, are advised to leave the air box stock.

Andy
 
PK001 said:
Arrow Headers, Leo Vince Slip-on, AIS Blocked, Standard Airbox (Previously LARS Airbox), K&N Filter, Longer Velocity Stacks (Factory Pro), Shaved Secondary Butterflies (CD), Reflashed ECU, PCV

The bike only has 2600km's on it so it is still bedding in/tight
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I'm wondering how much your long stacks effected peak power. The Long stacks generally hurt peak power but improve low-mid range. The cut airbox has usually shown gains @ peak on most other dyno charts I've seen.

Guess my point is have the long stacks effected the cut airboxes usual gains ???
 
The change back to stock will not give more power, but will allow for easier tuning to achieve the target AFR of 13, which means the bike will generally run smoother and more consistent.
It was possible, but difficult to acheieve a target AFR with the cut airbox as there was a lot of variation between adding and subtracting fuel from the map over a very small rev range e.g. adding 10% at say 3500 rmp and having to subtract 15% at 4000 rmp. The map was 'all over the place' .

Considering the difficulty of tuning a cut airbox for a gain of only 1-2 HP at the very top end, where it will never be used on the street is pointless in my opinion.

I had to add more fuel in the lower rev range with the stock airbox, but it was a consistent measure over the lower rev range, which created a smoother AFR line and tells me the longer velocity stacks are doing the job of sucking more air in at this range and producing a little more torque in the low/mid area of the graph. I got the velocity stacks cheap so endded up using them, otherwis they too are a bit of a gimmick in my opinion.

Conclusion. Dont cut your airbox and dont waste money on stacks, the gains are negligible.
 
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whittlebeast said:
Going to MAP based tuning helps a bunch. TPS based tuning on the bottom end is almost impossible by comparison.

Beast
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Hi Andy,

I am very interested in trying out the Autotune module and LCD Data logger. Something i'm looking forward to doing in the future when funds allow. Andy, can you confirm if i can connect the LCD Data Logger to use strictly as an analysis tool without having to use the Autotune Module? Can an o2 wideband sensor plug directly into the LCD?

Reason im asking is i'd like to have the ability to review/analyse my bikes data and make adjustments manually rather than run the bike in Autotune mode.

Is there any other form of data logging other than Dynojet?

Cheers,
Paul
 
You can set the tuning authority to 0% and the autotune unit would only data log. The Dynojet stuff all works on a CAN network. The protocol is unique to Dynojet so sharing data like RPM or throttle position with other systems would be almost impossible.

Yes you could do all tuning by hand. The head programmer over at Megasquirt always hand tunes. I tend to autotune first but always hand tune at the end.

WOT tuning is almost always done by hand but that is by far the easy part of tuning. The real work is in the midrange and transitions.

Eventually you will run across the fuel shift that these bikes do relatively randomly. It is this fueling shift that caused me to run autotune all the time on these bikes. When it hits, the authority needs to be set to about 8% to cover.

Beast
 
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whittlebeast said:
You can set the tuning authority to 0% and the autotune unit would only data log. The Dynojet stuff all works on a CAN network. The protocol is unique to Dynojet so sharing data like RPM or throttle position with other systems would be almost impossible.

Yes you could do all tuning by hand. The head programmer over at Megasquirt always hand tunes. I tend to autotune first but always hand tune at the end.

WOT tuning is almost always done by hand but that is by far the easy part of tuning. The real work is in the midrange and transitions.

Eventually you will run across the fuel shift that these bikes do relatively randomly. It is this fueling shift that caused me to run autotune all the time on these bikes. When it hits, the authority needs to be set to about 8% to cover.

Beast
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Tuning authority....cool, so you can set the level of 'interference/changes' the Automodule does to the map? im guessing there are some parameters/base line it uses to determine when it has to make changes? Learning something new all the time. Thanks
 
AFR graph for comparison of different set ups. As you can see, the standard air box smoothed lower end up a little, but i guess the MAP based tune will help refine even further. It never ends......this is addictive :evillaugh:

AFR_zps418028d7.jpg
 
eurban said:
Here's a thread started by Ivan showing the differences he found with the airbox mod. The differences are a good bit more significant than what you found . . . .Ivan's results - Airbox mod and BMC filter - FZ1OA Message Board
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Ivans results are what I've seen to be more common with a modded airbox
5-8hp. I suspect having longggggggg stacks threw off the usual gains. Long stacks give gains down low at the expense of top end.
The modded airbox is a trade off and will make tuning a little harder at lower rpm's and part throttle but not impossible. The key for my bike was the accelerator pump settings .
Question is does 5-8 horsepower at peak make a better bike than one with long stacks and a stock airbox that fuels perfectly and has more power in the low mid range ?? ......I doubt it :)
The weak spot on these bikes is the power below 6000rpms not above.
I think gains down low will be much more appreciated to 90% of the riders than 5hp at peak.
 
Ivan's charts show gains of around 3hp starting as low as 4.5k rpms. That is a fairly significant gain in that all important midrange. The test mule (for both runs) had a slipon, fce, pciii, and ignition module as well. Presumably the mapping was optimized for both runs. Hopefully Ivan will comment here or on the other site. To even the most casual observer, the R1's factory engineered airbox has a dramatically larger intake and filter area with a much more direct air path. Does that mean that cutting the GenIIs airbox will help? It does kind of point that way but if I had my 06 on a dyno I would be inclined to test it out.
I am not sure the differences in results can be explained by the V-Stacks alone as Ivan is showing improvements fairly low down in the rev range. He does claim that the FCE opens the secondary flies earlier so that might explain some of the difference as well.
One other thing . . .Most of the shared maps (and Ivan's too) are optimized for the modded airbox so even if PK's results are correct it will likely mean tweaking (dyno time) the mapping to get things proper with a stock airbox.
 
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PK001 said:
Well here it is folks!

A back to back comparisson of the Lars airbox mod and the standard airbox. Dyno run was undertaken on same bike. The difference between the two dyno runs was swapping the airbox and the PCV map was retuned to acheive optimum A/F ratios for the changes. It was noted that aditional fuel had to be added (2-3%) when retuning of the map for the standard airbox to achieve the target AFR of 13.

Results are interesting to say the least.


LarsVsStandardAirbox_zps5d03a411.jpg
Click to expand...

How different were the maps for stock air box vs the modded one?
 
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