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Any benefit with Alpha air funnel kit with stock engine? I picked up a used set at a good price so I was going to try them.
 

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No real purpose. I seen them, bought them don't know what to do with them. For $190 why not I have wasted a lot more than this before.
 

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From the Alpha site, it sounds like this mod would require re-tuning, and should only be used in conjunction with camshaft and/or piston mods. That means the engine wouldn't be "stock"...so why do this?
 

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The engine is only going to inhale a certain volume of air through filter, air box, and into the engine. The cylinder is only so big.
I dont think it will do much without supporting parts.
 

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What's the purpose of this mod?
As soon as I can actually type because this forum sucks so bad...

These shorten the intake runner distance, which effectively shifts your power-band upwards, resulting in a power gain because volumetric efficiency improves with RPM. In order to take full advantage of these you'd need to raise the rev ceiling to 15 or so.

These also result in less restriction on the intake path, though that result is minimal compared to the resonant tuning mentioned above.

Any air flow change should get a tune.
Not at all, in fact the ECU can adjust for a wide range of airflow perfectly fine for our uses. Now for the guy wanting every last horsepower, then there is some to be had. But really tuning doesn't adjust for changes in airflow, tuning adjusts fueling/timing for all airflow values. For example Bren gains their measly power numbers by leaning the motor out some, and advancing timing some. Both of these decrease safety margin for bad fuel and other problematic conditions, but that's something a lot of us can live with as BMW leaves quite the margin to cover their bases.

The engine is only going to inhale a certain volume of air through filter, air box, and into the engine. The cylinder is only so big.
I dont think it will do much without supporting parts.
You're absolutely incorrect, that's why we make 200hp out of a 1 liter while a Honda makes just 150hp out of the same size engine. This is because, quite simply, our volumetric efficiency is significantly better. VE is the amount of air introduced into an engine versus the volume of the engine. So 100% VE means we would injest 1 liter of air for every 2 engine revolutions. It is generally accepted that 100% VE is approximately 100hp/L. So the BMW S54, S65, and S85 all run at approximately 100% VE. This is quite remarkable considering the relatively large size of the engines, and that they need to be street tuned. But compared to smaller sportbike motors, it's crap. Now by this formula we pull in 2 liters of air, effectively running at 14.7psi of "boost", in NA form. This formula is obviously a wildly inaccurate approximation, I don't for a second believe we get in double our engine volume. But the point is, our motors are substantially higher than 100% VE.

However, you're right about this not doing much without supporting parts. This is because these really only add power if the rev ceiling is raised, and we need supporting parts to raise that because the factory parts are all tuned for 14,000.

Any fuel change would do the same...

:grin2:
Not quite, in fact without touching the electronics or the pressure regulator, you really can't change fueling at all. Bigger fuel pump, bigger injectors, bigger fuel line, none of it will do anything ;)
 

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As @Dragor pointed out in the ECU thread, there are many factors at play in how the engine manages power. In particular upto 8000 rpm it tries to decrease volume to increase velocity by not opening the throttle as much as the rider asks until the revs can handle it.
BMW put the DISA servo on the S1000RR that adjusts the length of the intake manifold (stacks) under ECU control.

I think to get optimum use out of a change like intake manifold length you would need dyno testing, fuel and spark changes and probably adjustments to the DISA control graph (which is not in RCK2/3 so it custom ECU code for that one).
 

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The problem is this forum is not operated/owned/dictated by enthusiasts, it's done so for profit by someone who couldn't care less about the forum experience. And anytime someone mentions something about it being slow, they point the finger at the user. Check your browser! Check your WiFi! Check your surgery protector! Nope, then it must be your mouse.

What needs to happen, is someone with the money, time, and knowlegde needs to start a decent forum. Competition breeds excellence. This forum will either have to step up, or it'll wither and die.
 

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And that's where you're wrong. I have never made a cent off being a mod. Only things I've gained are knowledge and life long friends so STFU!

Go start another forum or join another one. Otherwise, stop bitching. Also, you were raving about how great this community is when you were asking for money. It didn't prevent you from posting a thread asking for money.
 

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Control yourself. You've got some serious issues if you're trying to find negatives with someone donating a bicycle to a guy who can't walk.

But just like every other of the hundreds of threads on how poorly this forum runs, they turn it around on the user.

As far as the money you've made, I've got every reason to believe you're lying.
 

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Control yourself. You've got some serious issues if you're trying to find negatives with someone donating a bicycle to a guy who can't walk.



But just like every other of the hundreds of threads on how poorly this forum runs, they turn it around on the user.



As far as the money you've made, I've got every reason to believe you're lying.

Going back to the point, don't leverage the forum for anything if you hate it so much. Just go away. Let's ask other mods if they make any money. Let's ask mods of other forums if they make money. Let's make a clear distinction. I'm a moderator of this forum. I volunteer as I already visit this forum. I'm not an admin, who may be employed by forum owner.
 

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You're probably getting paid, of course you like it.

I lack the knowledge, time, and money to go start a forum.
I'm not getting paid, and I like it. It's neither slow, nor useless. Try using an ad blocker. When I did that, this site worked 10X faster.

And saying sro is "lying" is way out of bounds. Something else is going on here and I'd be surprised if anyone but a psychotherapist (who IS getting paid) would be interested in digging out just what that is.
 

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The air funnel wont do much based on how the engine operates. You arent changing parts such as cams ( to allow higher lift, longer duration, rev limiter, head flow characteristics, so i dont think you "feel/ notice " gains.

If you want to just spend money for it go for it.
 
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