Air box runner lengths?

[04gtstang]

I was just looking at my air box for the first time, and noticed the rubber manifold runner extensions (well thats what they do in reality). The ouside (pistons 1 and 4) rubber extentions are pretty short, but the middle extentions are quite abit longer and curve toward the center of the box and look to limit the amount of air that can enter as its near the top of the box.

This seems to me that the 2 middle cyclinders are getting fed more air at low RPM and less on the topend. due to the extra length and restriction.
That doesnt seem like a good design...all cyclinders should be fed the same amount of air ideally or everything will not be in perfect sync, especially @ 11,000RPM as the loads will be different and would probably cause a slight vibration.
Or am I just not seeing something here? It looked like each TB flows directly into each cyliner...didnt see a common inner plenum that they all fed into.

And are the fuel injectors individually controlled by the ECU to give the correct fuel to its cylinder depending on which runner extention it has, if this infact how its seup?

Anyone just bought 2 more short rubber pieces and replaced the 2 center ones?
Yea im a

to busas....but not to engines.

Just wondering if im missing something.

 

[heavybusa]

bueler

 

[04gtstang]

I knew I forgot something! LOL

I searched the airbox mod quite abit, and everyone just guts it and pulls all the rubber pieces. IMO it will flow BETTER with those short runners, so im not pulling them.

 

[MoosesBusa]

Schnitz racing sells 4 short runners in a kit. I have been told why before and after it was explained to me I understood why. Satisfied, I promptly replaced that memory with one at a topless club in Mexico.

As I vaguely recall, it has to do with balanced air flow for fuel econony/EPA regulations. Putting 4 short stacks helps you as does the air ram tube extensions. The extensions increase intake pressure allowing for more powerful suck bang blows at higher speeds.
Helpful?

 

[BA BUSA]

If you use all four short runners it helps to make more HP...all four long runners for a bit more torque.

So do you want MAX HP or better mid range torque...either way you go it's not a big difference.

 

[dadofthree]

 

[04gtstang]

Thanks for the help guys

. I MAY look into buying 2 short ones from suzuki, as im sure they have a part #. But ill look into the Schnitz racing one too.

But to me, it still doesnt make sence to make 2 cylinders excell @ low-mid range power, and the other 2 @ high RPM. I dont know what Suzuki was thinking, as thats not a good thing to do...unless like said, it helps with emissions and they dont give a crap is the motor is not breathing at an even equal pace LOL.

 

[heavybusa]

send me your long ones, I do love torque!!

 

[Burger King]

I don't know. Does it have anything to do with the 2 inside cylinders being just that, inside? Usually the inner cylinders generate more heat than the outer cylinders.....Just a thought.......

 

[heavybusa]

and the king rings in with a point...

 

[04gtstang]

(Burger King @ Nov. 30 2006,19:40) I don't know. Does it have anything to do with the 2 inside cylinders being just that, inside? Usually the inner cylinders generate more heat than the outer cylinders.....Just a thought.......

Doubt it. BUT it is POSSABLE as at high RPM, where the inner cylinders would be the hottest, it will supply them with less air. So basically they will be slightly richer and that will act to cool off both the EGTs and pistons.

Although with oil sprayers uner each piston, oil and water coolers...this motor shouldnt have any overheating issues at all while moving.
But who knows what they were thinking...bike pulls like a scalded ape stock, so maybe I shouldnt worry about it LOL.

BTW those schnitz racing runners are freegin expencive! Like almost $200 for 4 aluminum runners...thats crazy, they are worth about $80 tops.

I noticed that all the modifications are rediculously high for these bikes...I mean my FULL exhaust on my GT
(Ceremic coated BBK LTs, DR Gas O/R X pipe and SS magnaflow catback) costed me around $1100. Its about the highest flowing combo out there, and very high quality....the full exhaust on these bikes run around $1200 and im not sure if you even get the cans with that. I know there is alot of presision involved, but wow.

 

[8Daytona8]

The longer stacks actually give more air at hi rpm! Venturi effect.

effect.

 

[Big Tuna]

I am running all stock shorties now. To be honest, I havnt noticed alot of difference but Geez...Im a lard a$$. I ended up putting a want ad up and a fellow over at SH.org sent me 2 stock shorties for $10 shipped.

 

[04gtstang]

(8Daytona8 @ Dec. 01 2006,20:59) The longer stacks actually give more air at hi rpm!  Venturi effect.

effect.

Well the short runners have the same design as the long ones. I dont see longer ones providing more high RPM air flow.

Long runners are designed to promotote cylinder filling @ low RPM where the air can "stack" ontop of itself and when the valve opens, it forces more air in from its own weight. But as you increase RPMs, that long runner just acts as a restriction because the motor has to pull the air down the tube. Thats the way I understand it.

But please explain your point further if you dont mind, as to how the long runner of nearly the same inside diameter provide more high RPM air flow than the short ones.

 

[g-pack]

has any1 tried the velo stacks?? feedbacks,coz i'm thinking of getting them too,but,still i'm not sure...i had dual tip yoshi,dna filter,smart tre,small airbox mod,tekka mapped,muzzy clutch basket,pair valves removed from my baby  

 

[runeight]

(g-pack @ Jan. 20 2007,03:13) has any1 tried the velo stacks?? feedbacks,coz i'm thinking of getting them too,but,still i'm not sure...i had dual tip yoshi,dna filter,smart tre,small airbox mod,tekka mapped,muzzy clutch basket,pair valves removed from my baby  

save your money..no big gains.

I was going to do this but after further research and talking with Quasar (board member-awesome MAPS) the best results were with all long stacks.

It wasn't much but some. To each his own as some would disagree.

runeight...

 

[heavybusa]

Run knows his stuff

 

[runeight]

(heavybusa @ Jan. 20 2007,06:38) Run knows his stuff  

not really Greg. I just go with people who have the means to test, experiment and have done the research.

Quasar is pretty top notch in his field so therefore I trust what he suggests.

I save all his emails on various question I have asked in the past.

runeight...

 

[heavybusa]

just take the compliment!!

you are a humble man.

 

[GPW]

Guys, I will do a test with all short and all long on the dyno here. I just need to get all longs, have plenty of shorts. We will look at the torque curve as well. It is not always how high a number is in reference to torque but when that torque power comes on and how long does it stay in the rpm range...would you want (3) more foot pounds of torque or a torque curve that came on 500-800 rpm's sooner and lasted 500-800 rpms longer. Thats what I would want. All too often people get hung up in max dyno numbers and the real world performance goes out the window. Testing something in a controlled enviroment, lots of concepts are just thoughts until actually tested. Have your theories tested on your machine, not someone else's you may be surprised by what you have read on the web. Just my two cents. I like factual evidence and we will test it all here at HPC.