Airbox Modification

This has been beat almost to death but I was wondering if there is any sort of concensus or new information on a few things...

I have read the recent post by Armand as well as the Cdogman post and the Wicked Webby discussions as well as some related threads. Its a lot of reading and I can't really come to any conclusions. I have been thinking about modifying the airbox according to Cdog's process - it seems to be easier and less invasive than Webby's. Benefits (if any) should be similar.

I have a PC III which I removed some time ago because of fuel consumption issues and the removal sacrificed a SMALL amount of smoothness at low throttle and MAYBE a touch of power once it was opened up. I also have a set of Leo Vince cans which I removed a year ago because they were getting noisy and in need of a repack (haven't gotten around to it yet). I also have a K&N air filter on the bike although have considered replacing it with stock after reading some stuff on the forum. (I know, I shouldn't do so much reading.)

1) It seems to me that most proponents of airbox hacking are claiming an unmeasured improvement in power with smoother/faster acceleration. Not a lot of dyno evidence related to airbox alone; most include other changes such as full exhaust systems, Power Commanders, Barbarian mod etc. Comments?

2) Not much data (other than anecdotal) about the effect on fuel consumption. I would like to know more. If I wanted a fuel miser, I wouldn't have chosen the FJR but there's nothing wrong with getting the best economy possible. This can be a big issue on longer trips although less important when the focus is on having fun.

3) Comments seem to suggest that intake noise is a little greater (but not bad) and there are no documented problems of water ingestion causing performance problems.

4) If I go this route, is there any need (or benefit) in making fueling changes? Either by PC III or Barbarian Mod. Other reading has indicated that the four CO settings for the four cylinders are not always the same as each other in stock configuration. I wonder if this has anything to do with uneven air distribution between the cylinders as a function of the stock airbox configuration...

5) Would there be a benefit in going back to the Leo Vince cans? I suspect that the cans don't make nearly as much difference as using a header that is not restricted with a catalytic converter.

6) There seems to be a variety of opinions on how this affects intake vacuum and TBS. Easy enough to adjust and I am planning on installing block-off plates on the air induction system anyway.

This is a modification I will do if there is a reasonable expectation of a performance gain without sacrificing fuel economy or driveability. (Is it possible to get something for nothing?) The airbox parts are not stupid expensive so it wouldn't be a huge deal to restore to stock if I didn't like the outcome. Being essentially lazy, I thought I would like to be as well informed as possible.

Thanks

Ross

PS Glad I didn't make this post on a Friday.

Well...to me the bike runs so smooth with the stock airbox & filter that I don't see the point to put money in a PCIII and K&N intakes. I have aftermarket exhaust only and she purrs like a kitten and still gets very good gas mileage without those other mods. It already has 145hp at the crank in a stock setup.

Just seems like a lot of money to spend on minimal gains :huh:

GeorgiaRoller said:

Well...to me the bike runs so smooth with the stock airbox & filter that I don't see the point to put money in a PCIII and K&N intakes. I have aftermarket exhaust only and she purrs like a kitten and still gets very good gas mileage without those other mods. It already has 145hp at the crank in a stock setup.

Just seems like a lot of money to spend on minimal gains :huh:

Click to expand...

What expense? The airbox mod and the Barbarian Jumper mods are free. I already have the aftermarket cans, K&N filter and PC III if I decide to use them (bought by previous owner).

My opinion? Unless you have an engineering degree in flow dynamics

AND access to a dynanometer, any anecdotal info is worth what you pay for it.

IOW, I have no intention of entering a horse in this race.

RossKean said:

GeorgiaRoller said:

Well...to me the bike runs so smooth with the stock airbox & filter that I don't see the point to put money in a PCIII and K&N intakes. I have aftermarket exhaust only and she purrs like a kitten and still gets very good gas mileage without those other mods. It already has 145hp at the crank in a stock setup.

Just seems like a lot of money to spend on minimal gains :huh:

Click to expand...

What expense? The airbox mod and the Barbarian Jumper mods are free. I already have the aftermarket cans, K&N filter and PC III if I decide to use them (bought by previous owner).

Click to expand...

Oh ok well in that case if your bike already came with them I guess I can see your point of trying to make it all work better. I was just commenting on the point of messing with any of this in the first place.

I came from the Suzuki M109R riders forum and over their they are mostly obsessed with PCIII, K&N Intakes, Aftermarket pipes, Dyno running their bikes...etc. I actually got tired of the mod-crazy atmosphere and just wanted to "ride" not "mod". So I'm overexposed on this issue and most of the time it doesn't really seem to be worth the time/effort/expense for what you get in the end IMO.

With the FJR to me it just runs so well out of the box that I don't see a personal need to mess with it. But my bike didn't come with what yours has on it. Just my personal experience with it is all.

Ross,

I've done some mods to my airbox (cut off the snorkle and opened up the right side), along with changes to the CO settings (via the Barbarian mod). I'm running a PC-III with a tweaked version of a map that combines the Wally smoothness map and the Holeshot map. I have no statistical proof that it makes any improvements, but I personally think it's smoother and more responsive (and that's all that really matters). If you can wait until May when you come down, you can take mine for a ride and see if you like the changes before you do anything to yours.

Ed.

FJRed said:

Ross,

I've done some mods to my airbox (cut off the snorkle and opened up the right side), along with changes to the CO settings (via the Barbarian mod). I'm running a PC-III with a tweaked version of a map that combines the Wally smoothness map and the Holeshot map. I have no statistical proof that it makes any improvements, but I personally think it's smoother and more responsive (and that's all that really matters). If you can wait until May when you come down, you can take mine for a ride and see if you like the changes before you do anything to yours.

Ed.

Click to expand...

Thanks Ed, I may take you up on the offer. As I mentioned, I had a dyno-tuned PC III on the bike but removed it. I think I lost a little smoothness and maybe some top end in return for an almost 15% improvement in fuel economy. The dyno tune (done by the previous owner) was evidently purely for performance. I might give the airbox thing a try; not too expensive to undo by purchasing new parts. Regarding the Barbarian mod - do you think there is any advantage in doing a "broadband" richening when you can be far more specific with the PC III?

Ross

RossKean said:

FJRed said:

Ross,

I've done some mods to my airbox (cut off the snorkle and opened up the right side), along with changes to the CO settings (via the Barbarian mod). I'm running a PC-III with a tweaked version of a map that combines the Wally smoothness map and the Holeshot map. I have no statistical proof that it makes any improvements, but I personally think it's smoother and more responsive (and that's all that really matters). If you can wait until May when you come down, you can take mine for a ride and see if you like the changes before you do anything to yours.

Ed.

Click to expand...

Thanks Ed, I may take you up on the offer. As I mentioned, I had a dyno-tuned PC III on the bike but removed it. I think I lost a little smoothness and maybe some top end in return for an almost 15% improvement in fuel economy. The dyno tune (done by the previous owner) was evidently purely for performance. I might give the airbox thing a try; not too expensive to undo by purchasing new parts. Regarding the Barbarian mod - do you think there is any advantage in doing a "broadband" richening when you can be far more specific with the PC III?

Ross

Click to expand...

I just did my airbox the same way as FJRed and firstly noticed the increased intake noise. It howls more when cranking on it and drones more at steady throttle. I don't mind the extra noise but it is noticeable. My "butt dyno", (which, as a veteran expert racer, has become pretty sensitive and accurate) senses a little more pep in throttle pick up. Now how this translates into measured dyno #'s and 1/4 mile times, I do not know. If I grow tired of the extra intake noise, I'll just fashion a plate to cover the cutout and put the covers back on the access side. The snorkel will remain gone but IMO, is only there for EPA, etc. noise reduction reasons. Go for it. It's easy enough to undo.

BTW: PC maps can modded cell by cell. As long as you don't go crazy changing the #'s by a ridicules amount either way from a good map, you can pick up a couple MPG while still having improved fueling.

FJRed said:

Ross,

I've done some mods to my airbox (cut off the snorkle and opened up the right side), along with changes to the CO settings (via the Barbarian mod). I'm running a PC-III with a tweaked version of a map that combines the Wally smoothness map and the Holeshot map. I have no statistical proof that it makes any improvements, but I personally think it's smoother and more responsive (and that's all that really matters). If you can wait until May when you come down, you can take mine for a ride and see if you like the changes before you do anything to yours.

Ed.

Click to expand...

Having a PCIII and doing the Barbarian mod at the same time makes absolutely no sense to me. Can you try to explain what the advantage is of doing BOTH those mods?

I have to agree with the above. I had both the pciii and the barbarian mod. I found that putting the co settings back to stock and running with just the pciii settings that the bike ran better, smooth and yielded much better MPG. Butt Dyno felt nothing, face Dyno got a huge smile.

But then again, I do own the faster 03 model...

RossKean said:

1) It seems to me that most proponents of airbox hacking are claiming an unmeasured improvement in power with smoother/faster acceleration. Not a lot of dyno evidence related to airbox alone; most include other changes such as full exhaust systems, Power Commanders, Barbarian mod etc. Comments?

Click to expand...

Wicked Webby showed dyno results: https://www.fjrforum.com/forum//index.php?showtopic=102302

There's a significant gain (up to 10+%) in the 3700 to 5200 RPM range. He did some crude fuel adjustments via the CO settings and has stock header with Remus Hexacone slip-ons. The only difference between his before/after runs were air box mods and fuel changes. Mods without fuel changes are not worthy of comparison because any modification to engine airflow should be accompanied by fuel adjustments to match the new airflow.

I was able to reproduce that same gain in the 3700 to 5200 RPM range: https://www.fjrforum.com/forum/index.php?showtopic=120164

That was with the same air box mod, a Holeshot header and Remus Hexacone slip-ons. Fuel adjusted to 13.2:1 air-fuel ratio (essentially a custom dyno tune).

Unlike Wicked Webby, I had a loss in the high RPM range. Already discussed a lot in my linked thread, but basically I have enough evidence to convince me that switching back to the stock header fixed the high RPM loss and did not affect the mid-range gain. Furthermore, I also switched from the Wicked Webby mode to the cdog mod (because of this) and have evidence that it did not affect my mid-range gain. I'm quite confident that the cdog mod is just as effective as the Wicked Webby mod, and will give you that significant mid-range gain... at least if you have free-flowing slip-ons and adjust the fuel appropriately.

FYI - my "evidence" of how my changes affected my torque curve after my initial dyno results are not just butt-dyno results. It's based on comparing resulting fuel injection offset maps from my Motty AFR Tuner that automatically tunes the map as I ride, much like a PCV with AutoTune. For example, there was no change in my injection maps when switching from Wicked Webby's to cdog's air box mod, but there was a significant increase in fuel in the high RPM range when switching from the Holeshot to the stock header. Note that this may have been an interaction between the Holeshot header and Remus Hexacones that caused the loss. The full Holeshot system has been shown to not have any losses anywhere in the RPM range.

Pickles.

Thanks for the detailed reply. If I decide to go this route, I guess I'll do it right - largely based upon what you have said. I've already got the after market exhaust with the Leo Vince cans and have a Power Commander III I could put back on the bike. As you mentioned, better breathing without more fuel in the appropriate ranges probably wouldn't be helpful. No point in a PC III (especially with a non-stock airbox) without a couple of dyno runs to optimize it!

Other than the dyno, there's no real expense for me, except for the cost for re-packing the cans. They were getting pretty noisy before I took them off. The biggest potential expense is the added fuel costs over the next few years. I would think a modest improvement in air flow without major fuelling changes would not have a large effect on fuel consumption but it would depend on how far you went with the changes. While I appreciate a more lively ride, I do quite a bit of long distance riding where I want to maximize the distance between gas stops. The ideal setup is, of course, the one you have where you can flip between "go fast" and "economy" modes. Not really an option for me unless I want to buy a different fuelling system.

Since you never get something for nothing, what might you expect in terms of change in fuel consumption assuming I don't have too much fun with the new-found power? I can currently get as much as 50 mpg @ 50-55 mph but that never happens. More like low to mid 40's with fairly modest highway riding. Upper 30's if I'm having fun. I should note that these mileage numbers were MUCH worse when I had the PC III on the bike that had been (supposedly) dyno-tuned by the previous owner.

Ross

MPG is so dependent on local and personal factors that I won't try to answer beyond the general idea that you will obviously see a reduction in MPG if you have the fuel injection system modified in any way to provide more fuel in partial throttle cruising RPM ranges.

Try leaving the stock oxygen sensor plugged in when you reconnect the PCIII. You'll get the custom dyno-tuned benefits when you're accelerating and operating at high throttle positions and high RPMs, but still get decent cruising MPG due to the stock ECU's "closed-loop" mode that targets a 14.7:1 air:fuel ratio. This means that you might still experience some lean hesitation/surging in some situations that would otherwise be reduced/solved by the custom tune. Just gotta try it and see how it works for you.

UselessPickles said:

RossKean said:

1) It seems to me that most proponents of airbox hacking are claiming an unmeasured improvement in power with smoother/faster acceleration. Not a lot of dyno evidence related to airbox alone; most include other changes such as full exhaust systems, Power Commanders, Barbarian mod etc. Comments?

Click to expand...

Wicked Webby showed dyno results: https://www.fjrforum.com/forum//index.php?showtopic=102302

There's a significant gain (up to 10+%) in the 3700 to 5200 RPM range. He did some crude fuel adjustments via the CO settings and has stock header with Remus Hexacone slip-ons. The only difference between his before/after runs were air box mods and fuel changes. Mods without fuel changes are not worthy of comparison because any modification to engine airflow should be accompanied by fuel adjustments to match the new airflow.

I was able to reproduce that same gain in the 3700 to 5200 RPM range: https://www.fjrforum.com/forum/index.php?showtopic=120164

That was with the same air box mod, a Holeshot header and Remus Hexacone slip-ons. Fuel adjusted to 13.2:1 air-fuel ratio (essentially a custom dyno tune).

Unlike Wicked Webby, I had a loss in the high RPM range. Already discussed a lot in my linked thread, but basically I have enough evidence to convince me that switching back to the stock header fixed the high RPM loss and did not affect the mid-range gain. Furthermore, I also switched from the Wicked Webby mode to the cdog mod (because of this) and have evidence that it did not affect my mid-range gain. I'm quite confident that the cdog mod is just as effective as the Wicked Webby mod, and will give you that significant mid-range gain... at least if you have free-flowing slip-ons and adjust the fuel appropriately.

FYI - my "evidence" of how my changes affected my torque curve after my initial dyno results are not just butt-dyno results. It's based on comparing resulting fuel injection offset maps from my Motty AFR Tuner that automatically tunes the map as I ride, much like a PCV with AutoTune. For example, there was no change in my injection maps when switching from Wicked Webby's to cdog's air box mod, but there was a significant increase in fuel in the high RPM range when switching from the Holeshot to the stock header. Note that this may have been an interaction between the Holeshot header and Remus Hexacones that caused the loss. The full Holeshot system has been shown to not have any losses anywhere in the RPM range.

Click to expand...

As usual, great post pickles. I had not seen all this data before, but it confirms what my "butt dyno" felt after I did the mod. Interesting notes on the Remus baffle inserts, in or out, and changes to power. I haven't tried the baffles in yet but think I will now.

UselessPickles said:

MPG is so dependent on local and personal factors that I won't try to answer beyond the general idea that you will obviously see a reduction in MPG if you have the fuel injection system modified in any way to provide more fuel in partial throttle cruising RPM ranges.

Try leaving the stock oxygen sensor plugged in when you reconnect the PCIII. You'll get the custom dyno-tuned benefits when you're accelerating and operating at high throttle positions and high RPMs, but still get decent cruising MPG due to the stock ECU's "closed-loop" mode that targets a 14.7:1 air:fuel ratio. This means that you might still experience some lean hesitation/surging in some situations that would otherwise be reduced/solved by the custom tune. Just gotta try it and see how it works for you.

Click to expand...

Thanks, again...

When I had the PC III on the bike (with the LV cans), fuel mileage was quite poor - probably 15% fewer MPG. It didn't seem to matter much whether I was riding at highway speeds or putting around at low rpm. I think the custom PC tune was dumping in a bunch of fuel at low rpm for smoothness and even some at higher throttle positions for another couple of ponies. I have no idea whether the dyno shop where it was done was any good and I never received a copy of the dyno report (previous owner showed me a receipt so I know some dyno work was done). I probably should have tried some different maps but ended out just pulling it off the bike.

I tried unplugging the O2 sensor (ran it like that for a few months) and while it might have made a slight mileage improvement, it wasn't much.

I'm actually pretty happy with the way the FJR runs. Like most people, I wouldn't mind getting something-for-nothing or at least getting a noticeable improvement in power or driveability without sacrificing an up-front major cost, long-term additional cost at the pump or any degree of mechanical reliability.

Ross

The only other item to note would be the cats. Removing them would improve air flow even more.

I have the PCIII and the O2 sensor disconnected. Tried connecting the sensor, but found the compromise in the smoothness gains from the PC didnt make it worth it. YRMV?

I have the PCIII and the O2 sensor disconnected. Tried connecting the sensor, but found the compromise in the smoothness gains from the PC didnt make it worth it. YRMV?

Factory CO settings

A Tired subject I know but as yet not resolved in my mind.

Are the CO settings different for some cylinders and model years because:

1 Fuel Injection nozzle spec. inconsistency?

2 motor control computer changes year to year?

3 intake air volume inconsistencies cyl. to cyl. because of air box issues (snorkel,asymmetrical opening)?

We "HOME GAMERS" need guidance .

MY 06 performance mods are:

1 Trooper mod

2 Cdog air box mod

3 O2 sensor eliminator

4 Barbarian mod

5 air injection eliminator plates

6 NO PClll

WHAT CO VALUES DO I RUN (+7,+12,+30,all the same)? .What is the consensus?

Do I need to re-sync the throttle bodies?

The Forum is a great source!

thanks

Bill P