Power Mods: Exhaust, BJM, and Intake Box

[DaveFJR]

OK, just for discussion sake::

The stock inlet opening is exactly the same area as the area of the opening of one throttle body inlet. I'm not sure if there is overlap of intake stroke between the four cylinders but if only one cylinder is in intake, then the throttle body & air box opening match. I think the stock snorkel & opening would cause a pressure drop (pressure drop along a pipe as well as venturi effect) so a wide open flat panel will have the lowest pressure; but I wonder how much is needed?

 

[Wicked Webby]

Dave,

Cylinders #1 and #4 share the same stroke/cylinder timing, as respectively cylinders #2 and #3 do. Your question (I think) brings up the same scenario.. When is there enough air?.?.?

I will say this...

You will only max your air capacity out when your fuel input and exhaust output can no longer compete/compliment the extra air input. Thus, you are unable to specifically tune the correct AFR. I have found that I cannot over air my FJR's setups.

So, once you have established your level of output (exhaust restrictions.. or lack of).. Start adding the correct amounts of fuel with as much air as possible until you can no longer maintain the proper AFR.

How do you measure this.. With a Dyno and sniffer.. And/Or road tests with a portable 02 sniffer/analyzer. A lot of runs/pulls too!!!

During my Dyno testing.. I found that the more air the better.. For example...After a lot of Dyno runs, I discovered that with my modded air box and +14 CO values gave me the 138hp... I was running out of tire life (getting into and past the cords). Thus, I had to limit my runs and time... I did one more pull, again with my air box modded (opened up as much as possible), and added even more fuel.. This time +20 CO values... This test revealed a loss of 2-3 hp at the tire.. Compared to the plus +14 Thus.. I figured that I had a very small window of CO levels to do some road test with (against other bikes). Respectfully +15 to +19.. I have since done a lot of this and have found +17 to be very good.. Like I told SB360 during our previous discussions.. I had evened out the fuel on all four of my cylinders to accomidate my air being fairly even with hardly any air resistance from the air box. Hence, 35,35,35,35 has been my CO levels.

I know (from experience) that if I were to pressurize my intake to say 800cfm's(supercharger/blower)... I could add more fuel (than I currently have) and most likely get more HP/TQ.. If it wasn't too much for my exhaust. Though, I am not interested in having that much money into my bike.. Besides.. My ride already spins up WAY faster than I really need it too..(Ain't that right Gramps )

Take care all,

Happy HP Hunting!!

WW

 

[Gramps]

Though, I am not interested in having that much money into my bike.. Besides.. My ride already spins up WAY faster than I really need it too..(Ain't that right Gramps )
Take care all,

Happy HP Hunting!!

WW

Before I met you WW I thought mine was fast enough...you're a bad influence my friend. If I was a little kid my mommy wouldn't let me play with you. :grin:

 

[Wicked Webby]

Though, I am not interested in having that much money into my bike.. Besides.. My ride already spins up WAY faster than I really need it too..(Ain't that right Gramps )
Take care all,

Happy HP Hunting!!

WW

Before I met you WW I thought mine was fast enough...you're a bad influence my friend. If I was a little kid my mommy wouldn't let me play with you. :grin:

Gramps,

Hahahahahahaha! Now that is way too funny!! I know you probably won't believe this BUT.. I may have heard something very similar in the past!!!

Ain't it just a hoot to pretend to be all grown up and then swing a leg over your two wheel terror and dance with the Devil for a spell!!!

:lol:

WW

 

[Gramps]

Ok, got the preliminary report on my bike after the Dyno tune & I have not ridden it yet.

Based on the air box mod I did (similar to SB360), it was definitely starving for fuel, so that was adjusted.

There's a noticable difference in the throttle response...it a lot better!

My mechanic said it should be more responsive through the mid range(haven't had a chance to test that out as yet),

which is what I was kind of hoping for...I'm not one for running all out top end. :scare2:

Overall, the air box mod with a PCIII, K&N filter & stock pipes will get you about 5 hp more.

I'll report back with whether or not all this seems hold together after I get a chance to ride this weekend.

 

[Philip]

Ok, got the preliminary report on my bike after the Dyno tune & I have not ridden it yet.Based on the air box mod I did (similar to SB360), it was definitely starving for fuel, so that was adjusted.

There's a noticable difference in the throttle response...it a lot better!

My mechanic said it should be more responsive through the mid range(haven't had a chance to test that out as yet),

which is what I was kind of hoping for...I'm not one for running all out top end. :scare2:

Overall, the air box mod with a PCIII, K&N filter & stock pipes will get you about 5 hp more.

I'll report back with whether or not all this seems hold together after I get a chance to ride this weekend.

are you planning aftermarket pipes im sure that would add another 5-8hp.

 

[Gramps]

are you planning aftermarket pipes im sure that would add another 5-8hp.

Not at this time, but it is in my future plans.

 

[DaveFJR]

are you planning aftermarket pipes im sure that would add another 5-8hp.

Not at this time, but it is in my future plans.

WW:

I thought about what you said “Cylinders #1 and #4 share the same stroke/cylinder timing, as respectively cylinders #2 and #3 do.” So, I looked at the picture of the intake camshaft in the repair manual and the intake cam lobes are 180 degrees apart between 1&4, 180 degrees apart between 2&3, and 90 degrees from each pair (1/4 & 2/3). So, only one cylinder is in intake at a time and there is no overlap of intake stroke between the four cylinders (otherwise the power pulses would be like a twin.) So, the stock inlet opening is exactly the same area as the area of the opening of one throttle body inlet. I’m not arguing your results but I think it’s interesting the engineers designed the air box opening to match.

 

[Gramps]

Ok, I said I would report back after I had a chance to do some road tests. Since I initially (prior to modifying the air box) had tried to see how my bike would stack up to Wicked Webby's I thought that it would be interesting to see if I had improved anything after opening up my air box & having the PCIII remapped. Granted, our test runs were not based on anything scientific, but it did give me a good perspective on how much of an improvement the changes made. And in my opinion the changes were a very noticeable an improvement. A little more horsepower (Dyno'd approx. 5 hp more), but what has impressed me the most is the improved throttle response.

I still wasn't able to stay with WW, but at least now he's not running away at the same rate as before. All in all it's a inexpensive investment for a little more fun, some may think it's just a lot of crap & that's ok. I just think it's cool how versatile this bike is & the things you can do to it to make it your own. I would recommend opening up the air box to anyone, with or without after market pipes, just letting the bike breath a little more is an improvement IMO.

With that, as soon as I get a copy of my new PCIII map (hopefully this week), I'll post a link so that anyone who wants it can download the file.

None of this would have caught my curiosity if it had not been for WW. Thanks buddy!! :clapping:

 

[Wicked Webby]

are you planning aftermarket pipes im sure that would add another 5-8hp.

Not at this time, but it is in my future plans.

WW:

I thought about what you said “Cylinders #1 and #4 share the same stroke/cylinder timing, as respectively cylinders #2 and #3 do.” So, I looked at the picture of the intake camshaft in the repair manual and the intake cam lobes are 180 degrees apart between 1&4, 180 degrees apart between 2&3, and 90 degrees from each pair (1/4 & 2/3). So, only one cylinder is in intake at a time and there is no overlap of intake stroke between the four cylinders (otherwise the power pulses would be like a twin.) So, the stock inlet opening is exactly the same area as the area of the opening of one throttle body inlet. I’m not arguing your results but I think it’s interesting the engineers designed the air box opening to match.

Dave,

First, Thanks for pointing this out. I didn't take any of your statements as arguments. FYI, my reference to cylinders #2 & #3's sharing the same cylinder stroke timing wasn't meant to be in regards to the valve/cam timing.. I was referencing how cylinders #1 & #4 share the same cylinder stroke time and are balanced (off set) by cylinders #2 & #3 stroke time. Timing was a poor choice of wording there...My bad on how it kinda reads in a way that I referenced the valve/cam timing instead of cylinder stroke times.

My thoughts about the air box horn and small inlet cover is more on regards to this... Yamaha engineers were not tasked only to make the FJR1300 as POWERFUL as they could BUT had a lot more to consider..... A balance of R&D costs, manufacture costs, Hp/Tq, and the biggest passing noise/emissions.

I know from experience (on the dyno and road testing with Friends.. My C14 buddy and just today with Gramps) that the MORE air and right amount of fuel you can put into your FJR.. Along with the quicker you can let it all out.. EQUALS a very FUN FJR!!!

THE WAY OUR FJR'S ARE DESIGNED... YOU CANNOT OVER INFLATE IT WITH AIR... LET UM BREATH!!! JUST ADD ENOUGH FUEL!!

WW

 

[Wicked Webby]

Ok, I said I would report back after I had a chance to do some road tests. Since I initially (prior to modifying the air box) had tried to see how my bike would stack up to Wicked Webby's I thought that it would be interesting to see if I had improved anything after opening up my air box & having the PCIII remapped. Granted, our test runs were not based on anything scientific, but it did give me a good perspective on how much of an improvement the changes made. And in my opinion the changes were a very noticeable an improvement. A little more horsepower (Dyno'd approx. 5 hp more), but what has impressed me the most is the improved throttle response. I still wasn't able to stay with WW, but at least now he's not running away at the same rate as before. All in all it's a inexpensive investment for a little more fun, some may think it's just a lot of crap & that's ok. I just think it's cool how versatile this bike is & the things you can do to it to make it your own. I would recommend opening up the air box to anyone, with or without after market pipes, just letting the bike breath a little more is an improvement IMO.

With that, as soon as I get a copy of my new PCIII map (hopefully this week), I'll post a link so that anyone who wants it can download the file.

None of this would have caught my curiosity if it had not been for WW. Thanks buddy!! :clapping:

Gramps,

Thanks!! I can say it because I seen it myself....

Your bike runs out way better than it did before!!

It is like a night and day improvement!!

I will let you know when we are having the farkle clinic at Rich's.

We will get your cylinders even steven.

WW

 

[Gramps]

I finally retrieved the new fuel map from my PC & making it available to anyone that wants it.

Just email me ([email protected]) & I'll send you the file. I think that UseLessPickles will also be making the file available on his website...he'll have to post the link.

Here are the particulars:

'05, Power Commander III, K&N air filter, stock pipes & air box mod (SwitchBlind360's mod).

 

[Wicked Webby]

Gramps,

Good work! I suspect many will appreciate your kindness.

FYI, for those sharing PWC maps. Remember a custom map is a custom tuned/sniffed for a particular bike, for particular conditions(weather factors and more importantly Elevation). I have seen exact same model and year bikes with the same mods using very different PWC maps for max HP/TQ in the same geographical areas on the same dyno. That being said, if I had the same year,model, exact mods, and lived in the same Geographical area I would not have a problem using anothers' custom map. Though, it may not be perfect for my bikes performance.. It shouldn't hurt it.

Here in the Twin Cities, MN we are around 900 above sea level. If your elevation is a lot different than ours Gramps' custom map will most likely not be a good match. Remember..If you run your bike too lean for too long you will be needing to tune into Ponyfool's thread on engine removal.

WW