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Tom, let me tell you a little story about 900RR's

Years ago I used to do a lot of jetting work for the dragracers in Memphis. 900RR's were fairly common and would whoop on a GSXR1100 only if the bike was properly jetted and the rider did everything exactly right.

900RR's in stock form had a dip in the power around 6000rpm and if you had the throttle pinned to the stop, in first gear acceleration when it came out of that dip it would lift the front wheel into the air.

Now when I would jet the carbs I would make the power delivery much more linear and it would remove that dip in power in the midrange. With the bike making better power through the midrange it would no longer loft the front wheel so early in the rev range instead it would take another 1500rpm or so before the front wheel would leave the ground. The rejetted carbs are now allowing the engine to produce more power throughout the rev range and the dyno charts backed this up, but the bike no longer snapped the front wheel up just past the midrange dip like it used to so some of the owners of these bikes complained and literally wanted me to put the old jetting back in because it felt faster to them when that hit of power would yank the wheel up.

The point is without actual baseline and end dyno charts to verify the results. It is all subjective even from you Tom...

Ultimately do any of you guys know of any other bike that has ever got 6-9 horsepower from an airbox mod alone? If some guy showed up on this forum claiming his ZX-10R or SV650 gained 6hp just from an airbox swap every single one of you guys would call him out on it, but when RC51 owners make similar claims it must be true. :rolleyes:

It makes no ****ing sense whatsoever.
There is better power with the t1 box on my bike and BETTER is the key word,because I do-not have proof and do not need to prove anything.
I was in the cell both times gains were acheived.

B.T.W 900 rr's are /were wheelie prone to the point that HONDA moved the cg.

If you know where one of these bikes is it would be real fun to watch Jamies Spragues (Sprague speedtuning) 1998 gsxr 11 have a go at it :D
 

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Damn Wingnutt, is that a picture of bigfoot? Holy pixels. :D

Here's another that gained 4hp and a couple of ft/lbs. Airbox, no other changes, stock internals.


"Subject bike has ported heads, PC3 usb, Arata slip-ons. Shows before/after of stock airbox vs. Durbahn, no other changes."
 

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LOL, I don't think it's considered hunting when he's pointing out the apex. Rick at Cogent was doing that for me at CMP last July, always a little humbling. :p Can't wait to go again next year!
 

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just to stir the pot here...

it seems as if ldh wants to discredit any claim of horsepower gains, sighting a need for dyno proof. when dyno proof is provided there is always something wrong with said dyno evidence.

if one wanted to be a real internet hero and prove everyone else wrong i would think one would produce dyno evidence to support their "no gain" claims.

if you wont believe anything that anyone else says without dyno proof is it out of the question for everyone else to request dyno proof of your claims? it seems as if your opinion is of the minority...

is there a single dyno chart (questionable or not) to prove LDH's claim? has anyone ever shown a loss with this "upgrade"?
 

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There are multiple claims on various forums of this aftermarket airbox mod alone is making 6-9 horsepower. Now we are down to 4hp from the charts above WITH PORTING which means it is not a stock engine.

I want to see these 6-9 horsepower gains with a stock engine in an apples to apples comparison. Until that happens I am calling bullshit.
 

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If any one of you bastards want to send me an airbox, I'd be happy to pay for the dyno time. :D

LOL I made that offer in the past and agreed to do all the dyno testing in one day on the same dyno and couldn't get anyone to commit.

Just finished compiling the run data from the gentleman on RC51forums with the otherwise stock engine. It is still not the complete picture I am looking for with a completely mapped baseline versus an aftermarket airbox mod only with a completely mapped final, but it does show a distinct pattern.


The Airbox by itself put a really big dip in the mid-range which would definitely make the bike feel like it was hitting harder as it came out of the dip.

Most of that was ironed out with mapping changes, but the end result is barely arguable as better than the stock airbox...

 

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Isn't that the same guy who had to replace his throttle bodies? Seems like he's been having a lot of fuel issues. The above dyno I posted is if I'm not mistaken a member here. He did the porting himself and to me 4hp is a considerable gain considering the weight loss also achieved and the price of the mod. Someone in that same thread asked you if you'd still be willing to test the box and you said you had no time or interest, etc etc. If you don't care to investigate it, maybe you shouldn't trash it so much.
 

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And there is the dyno proof...

Akdma the way I read the graph it shows a 4hp loss and then had to be tuned to achieve a 2 hp loss.

So ldh, is it a beneficial mod on an upgraded engine but a detriment to a stock engine? Is that where were going here?
 

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IF the BIG AirBox is no good:rolleyes: Why would Moriwaki have bothered with this?

You've GOT to remember Peps, the RAM-Air effect is got to be much Greater\Better with the BIG AirBox too!.....?


Anyways,... Mine SUX and I LOVE it!;) :D
 

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And there is the dyno proof...

Akdma the way I read the graph it shows a 4hp loss and then had to be tuned to achieve a 2 hp loss.

So ldh, is it a beneficial mod on an upgraded engine but a detriment to a stock engine? Is that where were going here?

That appears to be the case and it would coincide with the data I have gathered all these years on the RC and other bikes for that matter, but ultimately I do not know and that has been my entire point. Many of us have done mod after mod after mod to the stock engines and have seen virtually no gains outside of an exhaust and a Powercommander. Then people start showing up claiming these airboxes are instant bolt on horsepower goodness, but all the initial reports were always from guys that also did pistons, cams, full exhausts etc. There was never any proof the airbox alone did what it was claimed to do.

I have personally tested the Moriwaki airbox. It didn't do shit on the SP1 for performance. I mean it moved the dyno curves a tiny little bit, but it was totally nominal so small of a change that it could be simply environmental factors or maybe just the removal of the thermostat which was required to fit the Moriwaki airbox. Without the thermostat the bike runs in a different A/F ratio area.

As far as Moriwaki going to the trouble of making an airbox, well hello!!! They are in the business of making aftermarket parts so why not throw one on the table that is easier to work on, weighs less and costs a lot of money. Seems like a win/win situation for them to be able to make a custom airbox for a racebike team of theirs and then be able to offset the fabrication costs by selling it to the masses that don't know that it wasn't even built for the same spec bike as the production bike. As most of you know the production RC51's we bought DO NOT share one single bolt with the HRC Factory racebikes. The $107,000 HRC kit bikes were also pretty far removed from the production bikes so thinking parts made for that model would automatically work on the production bikes or even the basic racer white body bikes is just a pipe dream...
 

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If any one of you bastards want to send me an airbox, I'd be happy to pay for the dyno time. :D
I have one I can send. My bike is up for the winter and is sitting with the tank off right now, so it wouldn't be too difficult to pull the TB's and get the airbox out of there. PM me how you want to work the logistics and collateral, as long as I get the airbox back by early March.
 

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I have one I can send. My bike is up for the winter and is sitting with the tank off right now, so it wouldn't be too difficult to pull the TB's and get the airbox out of there. PM me how you want to work the logistics and collateral, as long as I get the airbox back by early March.
Somebody better step up, I want to see this!!!
 

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I have one I can send. My bike is up for the winter and is sitting with the tank off right now, so it wouldn't be too difficult to pull the TB's and get the airbox out of there. PM me how you want to work the logistics and collateral, as long as I get the airbox back by early March.
I didn't say anything about sending it back..... :D
 
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